JP3067589B2 - Small-diameter work roll hot rolling mill with biting assist device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot-rolled steel strip rolling plant and a hot-rolled steel strip rolling plant capable of realizing hot strip production at a speed commensurate with the production volume and realizing energy saving with a compact-scale facility. About the method.

[0002]

2. Description of the Related Art Conventional hot strip mills (hereinafter referred to as "hot strip mills"), for example, "Recent hot strip manufacturing technology in Japan" (incorporated association)
No. 176 of the Iron and Steel Institute of Japan issued on August 10, 1987)
Page and pages 305 to 310 have a production volume of 300 to
4 million tons / year and finish rolling speed of 680 to 1627
m / min and high-speed mass production rolling equipment
In a rough rolling mill that rolls slabs having a thickness of 20 mm to 20 to 40 mm,
2,000 to 1,300 mm diameter work rolls, and 20 to 4
It is described that a work roll having a diameter of 600 to 800 mm is used in a finish rolling mill for rolling a bar of 0 mm into a strip of 12 mm or less.

Recently, a slab of about 50 mm has appeared due to the development of a continuous thin slab casting method. In this case, a rough rolling mill is not required, and only a finishing rolling mill is required. The production method using these thin slabs was first applied to small-scale production. For example, "Ein Jahr Betriebserfahrung mit der
CSP-Anlage fuer Warmbereitband bei Nucor Steel ''
(Stahl u. Eisen 111 (1991) Nr. 1). Although the production volume is 700,000 tons / year, the number of finishing mills is 5-7.
It follows the conventional method with a stand rolling mill. The rolling speed on the exit side of the finishing rolling mill is 3 when the finishing thickness is 2.5 mm.
The speed is higher than 00 m / min and 600 m / min at 1.6 mm. The work roll diameter of the finishing mill is 7
It follows the conventional size of 60 to 800 mm.

On the other hand, Japanese Patent Application Laid-Open No. 6-320202 mentions the merit of using a small-diameter work roll from the viewpoint of the relation between the required production amount and the maximum speed of equipment or from the viewpoint of energy saving, and proposes a production system based on a new concept. I have. FIG. 1 shows a comparison of the required energy by rolling using a work roll diameter of 800 mm and 360 mm of a finishing rolling mill when a 200 mm thick slab is rolled into a 2 mm thick hot strip. From this, it is understood that energy saving can be achieved with the small-diameter roll.

[0005] The technique disclosed in the publication uses an indirect drive in which a small-diameter work roll is basically used for a finishing post stand that does not hinder biting, and the work roll is driven by an intermediate roll or a reinforcing roll. Adopt the method,
This is to prevent the temperature of the rolled material from dropping due to the strong reduction by the small-diameter work roll. It also aims to save energy by improving the rolling material deformation efficiency by using small-diameter work rolls.

Japanese Patent Application Laid-Open No. 54-149356 discloses that when a leading end of a material to be rolled hits a roll and a loop-shaped curved portion is formed at the leading end, a rear portion of the curved portion is restrained in a vertical direction. There is disclosed a device provided with a device for preventing the material to be rolled from moving backward, pressing the loop-shaped curved portion from above and below to advance the leading end of the material to be rolled and to bite into the roll gap.

[0007]

However, the adoption of the small-diameter roll described in the above-mentioned Japanese Patent Application Laid-Open No. 6-320202 is restricted by biting, and the roll-down amount is naturally restricted in applying to the pre-finishing stage. . Therefore, in this patent, when a small-diameter work roll is used for the first finishing stand,
A tip reduction device is installed to reduce the thickness of the plate before rolling.

Further, when a small-diameter work roll is used, there is a limit in torque transmission by a spindle, and an indirect drive may be performed by an intermediate roll or a reinforcing roll. In this case, it is necessary to have a friction coefficient between the work roll and the intermediate roll or the reinforcing roll that is higher than the friction coefficient required for biting. However, 100% cannot be guaranteed in actual rolling. There is a concern that a slip may occur between the rolls.

On the other hand, hot rolling oil between the plate and the work roll, which has the effect of reducing the friction coefficient and reducing the rolling load and the rolling power, should be applied under the conditions of biting even in the case of the conventional large-diameter work roll. Not done. Therefore, the effect of the hot rolling oil or the inter-roll lubricating oil cannot be fully utilized.

The reverse movement prevention device and the loop pressing device described in Japanese Patent Application Laid-Open No. 54-149356 restrain the material to be rolled in the vertical direction. Can be used only for cold rolling equipment with equipment that can store the material to be rolled so that the material to be rolled can be stopped at the entry side of the rolling mill, or a single stand rolling mill that repeats several times of rolling When rolling a material to be continuously rolled from a continuous casting machine, it cannot be used for tandem rolling in which a plurality of rolling mills are arranged.

An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a rolling facility that increases the productivity of a rolled material and saves energy.

[0012]

An object of the present invention is to provide a hot rolling apparatus for rolling a hot plate by a plurality of rolling mills provided with small-diameter work rolls. A passing plate guide member provided above and below a pass line of the plate material for guiding the progress, and a desired hot plate material installed near the passing plate guide member and guided by the passing plate guide member. And a roller that can be raised and lowered to a position, and guides the hot plate material between the work rolls.

In the above configuration, it is preferable that the roller is rotated by a driving device.

In the above configuration, the rolling mill provided with the small-diameter work roll has a detection device for detecting the hot plate material, and guides the hot plate material between the work rolls based on a result of the detection device. Preferably, a control device for moving the roller up and down is provided.

[0015] In the above configuration, among the plurality of rolling mills, a former rolling mill is the roller having a width smaller than the width of the hot plate material, and a subsequent rolling mill is configured to have the roller wider than the width of the hot plate material. Preferably, it is provided.

It is preferable that at least one of the plurality of rolling mills is a cluster mill that supports the work roll with a plurality of reinforcing rolls.

In the above arrangement, it is preferable that the work rolls of at least one of the rolling mills constituting the rolling mill row are ground online by a roll grinding device.

Further, the above object is to provide a pair of work rolls for rolling continuously fed plate material, a pair of intermediate rolls, a pair of reinforcement rolls, and a hydraulic device for applying hydraulic pressure to the work rolls. A rolling mill provided with the small-diameter work rolls, wherein a rolling guide provided on the upper and lower sides of a pass line of the strip to guide the progress of the strip, and This is achieved by providing a roller that is installed in the vicinity and that can move up and down to a desired position with respect to the hot plate material guided by the passing plate guide member, and guides the hot plate material between the work rolls. it can.

In the above structure, the pair of intermediate rolls preferably move along the roll axis direction of the intermediate roll.

Further, in the above configuration, it is preferable that the hydraulic device for applying hydraulic pressure to the work roll changes a contact force between the work roll and the intermediate roll in accordance with the elevation of the roller.

[0021] The above-mentioned object is also achieved in that the plurality of rolling mills move up and down the rollers so as to guide the hot plate between the work rolls based on a result of the detection device for detecting the hot plate. And a control device for operating the inter-roll contact force between the work roll and the intermediate roll.

In the above structure, at least one of the plurality of rolling mills may cross the work roll and the intermediate roll as a pair and change the profile of the gap between the rolls to change the sheet crown. Preferably, the rolling mill is

Further, in the above configuration, the work roll, the intermediate roll, the reinforcing roll, or each of the work roll and the reinforcing roll is provided with a curve that is asymmetric with respect to a path center and symmetrical with respect to a vertical point, It is preferable that the rolling mill be capable of changing the gap profile between rolls by moving the rolls in the roll axis direction.

The above object is also achieved in a four-high rolling mill comprising a pair of work rolls and a reinforcing roll and a device for spraying hot rolling oil on the work rolls. A passing plate guide member provided above and below a pass line of the plate material to guide the progress of the plate material, and a hot plate material installed near the passing plate guide member and guided by the passing plate guide member. And a roller capable of moving up and down to a desired position. The hot plate is guided between the work rolls while hot rolling oil is sprayed on the hot plate.

In the above configuration, it is preferable that the rolling mill is a rolling mill that crosses the work roll and the reinforcing roll as a pair and changes a profile of a gap between the rolls so as to change a sheet crown.

The above object is also a rolling mill provided with a small-diameter work roll for rolling a hot plate material, wherein the rolling mill removes the hot plate material before the hot plate material reaches the small-diameter work roll. This can be achieved by lowering the holding roll to a desired position and raising the holding roll when the tip of the hot plate material is bitten by the work roll.

[0027] The above object is also a rolling mill provided with a small-diameter work roll for rolling a hot plate material and a hydraulic device for applying hydraulic pressure to the work roll, wherein the rolling machine is configured such that the hot plate material is Before reaching the small-diameter work roll, the holding roll for holding down the hot plate material is lowered to a desired position, and when the tip of the hot plate material is bitten by the work roll, the work roll and the intermediate roll are moved by the hydraulic device. This can be achieved by increasing the contact force between the rolls and raising the roller after the work roll bites the hot plate material and returning the hydraulic pressure of the hydraulic device to a normal value.

Another object of the present invention is to provide a rolling mill provided with a small-diameter work roll for rolling a hot plate material and a hydraulic device for applying hydraulic pressure to the work roll, wherein the rolling mill suppresses the hot plate material. A roll having a roll, and after passing immediately below the press roll, the press roll is set at a position that restricts a sheet path so that a loop of a rolled material is not formed between the stands before being engaged with the next stand, Can be achieved by retracting the rolled material to a position where the rolled material does not come into contact with the rolls during the operation of the looper between stands after the bite is caught in the rolling mill.

[0029]

When a hot plate is rolled by a rolling mill provided with a small-diameter work roll, the hot plate is guided to the small-diameter work roll by passing plate guide members provided above and below the pass line. The plate bends upward due to the reaction force when being bitten by the work roll. On the other hand, the hot plate material is suppressed by a roller installed near the passing plate guide member and capable of moving up and down to a desired position with respect to the hot plate material guided by the pass plate guide member. Has a pushing force greater than the reaction force received from the work roll, and is bitten by the small-diameter work roll.

Also, when the hot plate material is engaged, hydraulic pressure is applied to the small-diameter work roll to increase the contact force between the intermediate roll and the work roll, thereby reliably transmitting torque to the work roll.
Ensuring the sheet material is bitten by the small-diameter work roll.

Similarly, the progress of the hot plate material is restricted by a passing plate guide for guiding the hot plate material to a large-diameter roll for spraying hot rolling oil and a suppressing roll for suppressing the hot plate material. Since the pressing force greater than the reaction force received from the work roll can be applied to the hot plate, the hot roll can be bitten by the work roll even when the hot rolling oil is continuously sprayed. it can.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic concept of the present invention will be described below with reference to a rolling mill using small-diameter work rolls as an example.

The first problem when using small-diameter work rolls is biting.

In general, the biting in rolling is performed by reducing the amount of reduction by Δ
h, roll radius R, rolling load P, mill rigidity K,
And the friction coefficient between the roll and the plate is μ

[0035]

Δh = μ ＾ 2 · RP / K (1)

Accordingly, when the roll radius R becomes smaller, the biting reduction amount Δh becomes smaller, and a biting failure occurs.

The amount of reduction is determined by the balance of the horizontal force between the force of the roll with the roll bite pulling in the material and the force of the rolling reaction force for pushing back the rolled material.

Now, the horizontal force acting on the rolled material in a state where the rolled material is bitten from the bite angle θo to θ is obtained.

[0039]

(Equation 2)

Here, Fθ: push-back force of the rolled material B: plate width km: restrained average deformation resistance R: work roll radius θo: bite angle θ: angle of plate tip position If μ is larger than (θo + θ) / 2, Fθ
Is negative and the rolled material is about to be pulled into the roll, but if it is small, it is pushed back. This pushing back force is Fθ
It is. Therefore, if a force larger than the push-back force Fθ is applied to the rolled material as an external force, biting can be realized even when the roll radius is small or the friction coefficient is low.

Now, assuming that the force required for pushing the rolled material into the rolling mill and the pushing force are F, from equation (2)

[0042]

Δh = R · (μ + √ (2 · F / (B · km · R))) ＾ 2-P / K (3) where R: roll radius μ: coefficient of friction between roll and plate B : Plate width km: Constrained average deformation resistance. Here, R = 230 mm, μ = 0.25, B = 1
FIG. 3 shows the amount of bite reduction when the value of F is changed from 0 ton to 10 ton with 200 mm and km = 10 kg / mm ² .
become that way. As is clear from FIG. 3, the biting reduction amount can be increased by increasing the pushing force.

Usually, an edger or a rolling mill is disposed in front of a rolling mill using a small-diameter work roll. The pushing force caused by this is a buckling force for bending the rolled material in the width direction and a lifting force of the rolled material. It is the sum of the required forces. And the force F1 for buckling the plate is

[0044]

F1 = (1.5 · π) ＾ 2 · EI / Lo ＾ 2 (4), and the force F2 required to lift the weight of the plate is

[0045]

F2 = 0.702 · w · Lo ＾ 2 / (a · π ＾ 2) (5) where E: longitudinal elastic constant of rolled material I: second moment of area of rolled material Lo: between stands Distance w: Weight per unit length of rolled material a: Expressed by 1/2 of the lifted amount of rolled material. Therefore, the pushing force F is

[0046]

F = F1 + F2 (6)

Now, the board width B = 1200 mm, the board thickness h = 10 mm,
Stand distance Lo = 5500mm, E = 7000kg / m
If m, I = 83000 mm ⁴ and a = 20 mm, F1 = 0.513 ton F2 = 10.15 ton, and the pushing force F is

[0048]

F = F1 + F2 = 10.66ton (7)

FIG. 4 shows that B = 1200 mm, h = 10 mm, and L =
The relationship between the lifting amount, which is the height of the buckling of the plate, and the pushing force when the thickness is 5500 mm is shown. From this figure, it is possible to obtain a high pushing force by reducing the lifting amount.

For example, the coefficient of friction between the roll and the plate is set to 0.2.
5, Rolling load 1500ton, mill rigidity 400ton / m
m and the roll radius is 230 mm, the rolling reduction Δh is given by the formula (1)
10.6mm. On the other hand, when the bite reduction amount is increased from 10.6 mm to 20 mm using the same roll diameter, a pushing force of about 7 tons is required as shown in FIG. In this case, as shown in FIG. 4, if the lifting amount of the plate is suppressed so that the lifting amount is 60 mm or less, a pushing force of 7 tons or more can be obtained. As described above, even if a work roll having a small diameter of 460 mm is used, a sufficient amount of bite can be obtained by controlling the amount of lifting of the plate. Here, for example, the force for suppressing the plate when the amount of lifting of the plate is controlled by the roll think about.

For example, in the case of a roll diameter of 460 mm, when the reduction amount is set to 20, the control is performed by the press roll so that the lift amount is 60 mm or less. Further, as for this holding force, when f is the height of the loop and L is the distance that the plate is lifted, f is approximately

[0052]

F = F · H / (L / 2) (8) where, if H = 50 mm and L = 3000 mm, only 1/30 of the pushing force is required. As described above, the plate can be sufficiently bitten with a very small holding force as compared with the very pushing force.

On the other hand, in a rolling mill using a small-diameter work roll,
It is difficult to directly apply the torque required for rolling to the work rolls, and there is no choice but to use indirect drive provided through a reinforcing roll or an intermediate roll. Usually, the rolling load is set in order to obtain a desired plate thickness, and it is assumed that the roll is sufficiently engaged with the plate. In other words, although there is no problem in the rolling in the steady part where the rolling load is applied, the load and torque are in a transient state at the time of biting, so that the friction coefficient necessary for biting between the plate and the roll was obtained. However, the same coefficient of friction is not always obtained between the rolls. Therefore, poor biting may occur. here,
When rolling torque is transmitted to a plate by indirect driving, the transmitted torque is obtained by multiplying the inter-roll contact load by the inter-roll friction coefficient and the roll radius. In addition, the friction coefficient required for biting and the friction coefficient for transmitting the rolling torque required for biting are substantially equal. In other words, if the required coefficient of torque cannot be transmitted due to the low coefficient of friction between the rolls, the required torque cannot be compensated by increasing the contact pressure between the work roll and the intermediate or reinforcing rolls to compensate for the low coefficient of friction. Can be given to the work roll.

Therefore, it is considered that the transfer force is increased by increasing the roll balance force in addition to the contact load generated by rolling and increasing the contact load by this force.

Assuming that the friction coefficient at the contact point of the roll is μr, the rolling load is P, the roll balance force is Fw, and the work roll radius is R, the transmission torque T1 by the indirect drive is

[0056]

T1 = μr · (P + Fw) · R (9) On the other hand, if the friction coefficient between the plate and the roll is μ, the torque Tr required for rolling is

[0057]

## EQU10 ## Tr = μ · P · R (10) Therefore, if T1> Tr, the plate can be engaged. From equations (9) and (10), T1−Tr = μr · (P + Fw) · R−μ · P · R = PR · (μr−μ) + μr · Fw · R> 0, and the roll balance force Fw is

[0058]

Fw> P · (μ−μr) / μr = P · (μ / μr−1) (11) Here, since the rolling load P differs depending on how far the plate is bitten at the time of biting, the rolling load at the steady portion is Po, the biting angle is θo, and the angle of the current plate tip position is θ.

[0059]

P = Po · (θo−θ) / θo (12) Therefore, the roll balance force Fw is (1
From equations 1) and (12)

[0060]

Fw> Po · (1−θ / θo) · (μ / μr−1) (13) In addition, when θ = μr, the necessary pushing force is maximized from the balance of the horizontal force of the plate in the biting roll bite. Therefore, when θ = μr and θo = μ are substituted into the equation (13),

[0061]

Fw> Po ・ (μ-μr) (μ-μr) / (μ ・ μr) = B ・ km ・ R ・ μ ・ (μ-μr) ＾ 2 / (μ ・ μr) = B ・ km R · (μ−μr) ＾ 2 / μr (14)

Now B = 1200 mm, km = 10 kg / mm, μ
= 0.3, μr = 0.25, Fw> 27.6 ton.

FIG. 4 shows that R = 230, B = 1200 mm, km
= 10 kg / mm, μ = 0.3 shows the relationship between the friction coefficient μr between the rolls and the necessary balance force. Therefore, poor engagement can be prevented by setting the roll balance force or bending force at the time of biting as large as the strength of the roll neck allows, and returning to the original balance force or roll bending force considering the sheet crown after biting.

As described above, in the rolling mill using the small-diameter work roll, the biting failure can be prevented by controlling the lifting amount of the plate and controlling the roll bending force or the roll balance force.

FIG. 6 shows a conventional four-stage finishing mill i-1 stand and i stand. Rolled material 1 is i-1
You are going through the stand and reaching the i-stand. Each stand has a housing 2 _i-1 , 2 _i , a work roll 3 _i-1 ,
3 _i , reinforcing rolls 5 _i-1 , 5 _i , work roll chocks 6 _i-1 , 6 _i , project blocks 9 _i-1 , 9 _i , roll balance or roll bending device 10 _i-1 , 1
0 _i , reduction jacks 11 _i-1 , 11 _i , reduction load cells (load cells) 13 _i-1 , 13 _i , entry-side passing plate guides 14 _i-1 , 1
4 _i , and the outlet-side passing plate guides 15 _i-1 and 15 _i .

As described above, the diameter of the work roll is more efficient for the deformation of the plate, and the smaller the roll diameter involved in the rolling is, the more efficient the roll can be made with less energy. In addition, the rolling load at that time also becomes small as well as the required power.
Therefore, from these viewpoints, the smaller the work roll diameter is, the better. However, the reason why the rolls actually used are so large is due to the biting condition. For example, the friction coefficient between the plate and the roll is 0.25, and the mill rigidity is 550t.
Assuming that on / mm, rolling amount is 20 mm, and rolling load is 2500 ton, the roll gauge becomes 760 mm from the equation (1), and usually 8 mm.
A work roll diameter of around 00 mm is selected. When this is rolled with a small-diameter roll of, for example, about 460 mm, it is necessary to push a rolled material when the plate is engaged.

FIG. 1 shows a rolling mill provided with a restraining roll for pushing a rolled material when the plate is engaged.

FIG. 1 shows a six-high rolling mill having a small-diameter work roll to which the present invention is applied. The 6-high mill work rolls 3 _i-1, 3 _i, intermediate rolls 4 _i-1, 4 _i, rolls 5 _i-1, 5 _i, supports the weight of the work rolls 3 _i-1, 3 _i roll Balance device 10 _i-1 , 10 _i , entrance side passing plate stands 14 _i-1 , 14 _i , exit side passing plate guide 15 _i-1 , 1
5 _i , holding roll 17 that can be raised and lowered by hydraulic cylinder
_i-1 , 17 _i , 18 _i-1 , 18 _i , the detecting device 19 _i , the lifting and lowering of the holding roll and the roll balance force of the roll balance devices 10 _i-1 , 10 _i based on the detection signals from the detecting device 19 _i. (Not shown) and an input device (not shown) for setting an initial value. Incidentally, suppressing the roll _{17 i-1, 17 i,} 18 i-1, 18 i can be rotated by a joint (not shown) by a driving device (M) but, even if not provided with a drive device present The rolling material aimed at by the invention can be sufficiently engaged. Here, the entry side passing plate stands 14 _i-1 and 14 _i are previously provided with the level differences H _i-1 and H _i between the roll bite and the table.
And has a slope that gradually approaches the roll bite level as it approaches the roll bite. Further, the control device and the input device may be provided separately from the rolling mill. Next, the operation will be described.

First, the operation of the pressing roll will be described with reference to FIGS.

FIG. 7 shows a state where the rolled material 1 passes through the i-1 stand and goes to the i stand. First,
A load P0 at the time when the rolling mill is engaged with the input device is set in advance. Further, the timings of lowering the pressing roll 18 _{i-1 of the} preceding rolling mill and the pressing roll 17 _i of the rolling mill which is to be engaged therefrom are set as t1 and t2, respectively. The values of the timings t1 and t2 are set according to the set speed of the rolling mill.

When the rolled material 1 is bitten by the work roll of the i-1 stand, the output signal of the load cell increases. Then, the control device compares a preset load P0 with an output signal from the load cell, and starts a timer when the load exceeds the preset load P0. Then, the restrained roll 18 _i-1 of the i-1 stand is lowered as shown in FIG 7 when exceeding the t1 time of timer preset. Then the restraining roll 17 _i of i stand is lowered as shown in FIG. 8 when the time of the timer exceeds t2. As is clear from this figure, the plate 1 is held down by the pressing rolls 17 _i-1 , 1
6 _i and the gaps H _i-1 and H _i between the entrance guide 14 _i and the table top of the exit guide 15 _i-1 . Plate 1
Moment which is meshed with i stand, strip passing guide 14 the plate 1 by the reaction force when biting by _i but is bent upward and buckling, Itado constraints roll 18 as shown in FIG. 9
lifting the _i-1 and 17 _i are Osaekoma. As described above, since the lifting amount of the plate material 1 is suppressed by the holding rolls 17 _i-1 and 16 _i , a sufficient pushing force can be obtained so that the rolled material 1 is bitten by the work roll of the i-stand.

In this way, the plate member 1 is bitten by the work roll 3 _i of the i-stand by a sufficient pushing force, and
Load detection signal of the load cell 13 _i of the stand is increased. The output signal from the load cell 13 _i of i stand raises the restraining roll 18 _i-1, 17 _i when becomes larger than a preset value. This is shown in FIG.
That is, an increase in the detection signal of the load cell 13 _i indicates that the work roll 3 _i of the i-stand is engaged with the plate material 1, and if the engagement is sufficiently performed, the suppression rolls 18 _i-1 ,
17 _i was elevated to start the looper 16 _i to initiate a looper control. In the present embodiment, the pressing roll is performed at the timing of the timer. However, the present invention is not limited to this, and a configuration for detecting the position of the plate material may be adopted. However, if the pressing roll is lowered early, it may come into contact with the plate material and damage the plate material. Therefore, it is preferable that the pressing roll be provided immediately before the plate material reaches the small-diameter work roll as much as possible. Therefore, a detector may be installed near the small-diameter roll, and the holding rolls 18 _i-1 and 17 _i may be lowered simultaneously with the detection of the plate material. The above processing is shown in FIG.
It is shown in FIG.

When a small-diameter work roll is used, the torque required for rolling cannot be directly input to the end of the work roll due to the strength of the spindle, so that indirect drive is input from an intermediate roll having a large diameter or a reinforcing roll. Therefore, there is a possibility that slipping occurs between the work roll and the intermediate roll or the reinforcing roll when the rolled material bites, that is, before the rolling load reaches a steady state. For this reason, i-
Balance cylinder 10 _i-1 of work roll of one stand
Output as large as the work roll neck strength allows,
Alternatively, by using the output of the work roll bending cylinder, the contact load between the work roll and the intermediate roll or the reinforcing roll is increased as the maximum output for a certain period of time after the engagement. This processing will be described in detail with reference to FIG. First, the biting load P0 of the rolled material, the balance force (or roll bending force) of the work roll, and the time ta are set. Here, when the load signal from the load cell of the i-1 stand exceeds the preset load P0, it is determined that the rolled material 1 has been bitten in the i-1 stand, and the work roll balance of the i stand is maximized. Maximize the contact force with the intermediate roll. When the output signal from the load cell of the i-stand exceeds the preset load P0, i
When it is determined that the rolled material has been bitten by the stand, a timer is started, and when the time exceeds a preset time, the roll balance force (or bending force) is returned to the set value. This solves the problem of biting that is most worrisome when a small-diameter work roll is used, and the small-diameter work roll can be used freely.

The shape of the pressing roll is not particularly specified, but has the following features. First, when a holding roll narrower than the width of the rolled material is used, the holding roll can be made smaller, so that the cylinder for raising and lowering the holding roll can be made smaller. Also, when using a holding roll wider than the width of the rolled material,
Since the pressing roll is wider than the width of the plate, even if it comes into contact with the plate, it is difficult to form a flaw. In addition, when the pressing roll is rotated by the driving device, it is possible to prevent the rolled material from being damaged by driving the rolled material at least until the rolled material is bitten by the work roll.

Further, in this embodiment, the configuration is shown in which the restraining rolls are installed on the entrance side and the exit side of the rolling mill, but they are arranged on one of the entrance side and the exit side depending on the distance between the rolling mills. Is also good. In addition, it is not necessary to use the same pressing roll on the entry side and the exit side of the rolling mill.For example, a holding roll narrower than the sheet width of the sheet material is provided on the entry side of the rolling mill, and a holding roll wider than the sheet width on the exit side. It may be arranged. In this way, the sheet material can be sent to the next rolling mill without damaging the sheet material on the exit side of the rolling mill. In addition, when a plurality of rolling mills are arranged, a pressing roll narrower than the sheet width is used in the first half rolling mill,
A control roll wider than the plate width may be used in the subsequent stage.

Next, the case where the roll change is performed will be described. When changing the rolls of the work rolls 3, if the entrance side passing plate guide 14 and the exit side passing plate guide 15 are left as they are, they come into contact with the work roll roll chock 6 and the work rolls 3 cannot be rearranged. . Therefore, as shown in FIG.
Rotate _i to the rising end. Then i is retracted from the stand by retracting the cylinder 21 _i to the entry side through-plate guide 14 _i of i stand is provided on the i-1 stand. Similarly, the delivery-side passing plate guide 15 _{i is connected} to the retract cylinder 20 _i
To evacuate. In this state, the work roll 3 is rearranged.

As described above, in the conventional finishing mill, a work roll having a roll diameter of 800 mm was used, whereas according to the present invention, a small work roll having a roll diameter of 500 mm or less (for example, a roll) Even a multi-high rolling mill having a diameter of 360 mm) can reliably bite a hot-rolled material.

Next, another embodiment to which the present invention is applied will be described.

FIG. 14 shows a four-high rolling mill in which hot rolling oil is sprayed on a work roll and a reinforcing roll to which the present invention is applied. This four-high rolling mill removes roll cooling water adhering to the roll surface from a spray nozzle 22 provided on the entry side of the work roll or a wiper 23 on the reinforcement roll entry side, and then feeds tallow oil from the spray header 24 to the roll. Alternatively, a hot rolling oil such as a synthetic ester is applied. Conventionally, in such a rolling mill, the frictional force between the work roll and the plate material is reduced by hot rolling oil, etc., so that poor engagement of the plate material occurs. For this purpose, the supply of the rolling oil is stopped before the rolled material 1 tails out, the rolling oil attached to the work roll surface is burned off, and in the rolling of the next material, spraying is started after the rolled material is completely engaged. . In such a method of preventing the poor biting of the sheet material, the effect of the hot rolling oil is effective only about half of the entire length. Therefore, as shown in FIG. 14, control rolls were provided on the entrance side and the exit side of the rolling mill. As a result, the reduction in the coefficient of friction between the work roll and the plate due to the lubrication of the hot rolling oil can be compensated for by the pushing force of the rolled material, so it is necessary to start or stop the supply of the hot rolling oil. And the hot rolling oil can be continuously supplied at all times, so that the hot rolling oil spreads over the entire sheet material.

The type of rolling mill shown in FIG. 15 has a pair of work rolls and a pair of reinforcement rolls, and the pair of work rolls is crossed together with a pair of reinforcement rolls supporting the same in a horizontal plane to form a rolled material. FIG. 16 is for controlling a thickness distribution of a rolled material in the width direction by crossing a pair of work rolls in a horizontal plane. Hot rolling oil is also used in such a type of rolling mill, and by applying the present invention, the rolled material can be reliably bitten in a state where the hot rolling oil is sprayed.

Further, as shown in FIG. 17, a rolling mill having a gourd-shaped crown-shaped roll and having a pair of intermediate rolls moved in opposite directions to control the thickness distribution in the width direction of the rolled material. Is also applicable.

The same applies to a cluster mill of a type in which a pair of work rolls are supported by a plurality of reinforcing rolls as shown in FIG.

The rolled material can be rolled into a small-diameter work roll or a large-diameter roll coated with hot rolling oil without stopping the progress of the rolled material by installing such a holding roll and controlling the roll balance force or roll bending force. In this case, the sheet material generated from the continuous casting machine can be rolled by a rolling mill provided with a small-diameter work roll. Further, in a rolling mill or the like provided with a roll search device, the roll diameter is reduced by the search, so that the roll diameter may be detected and suppressed to control the roll, roll bending force, and the like.

[0084]

As described above, according to the present invention, it is possible to provide a rolling facility using a small-diameter work roll without worrying about biting of a rolled material. By using such small-diameter work rolls, the rolling load can be reduced and a small-sized rolling mill can be provided.

[0086] Even with a large-diameter roll or a rolling mill that aims to reduce the load power by using hot rolling oil, the rolled material that is concerned can be bitten, and the rolled material can be rolled from the bite to the trailing edge. Oil rolling can be applied to the front region of.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an i-1 and i-stand 6-high rolling mill showing a threaded state (at the moment when the i-1 stand is engaged).

FIG. 2 shows the energy saving effect of a small-diameter roll in hot rolling.

FIG. 3 shows a relationship between a rolled material pushing force and a reduction amount.

FIG. 4 is a graph showing a relationship between a lifting amount of a plate due to buckling of the plate and a pushing force when the plate is engaged.

FIG. 5 is a graph showing a relationship between a friction coefficient between rolls and a necessary roll balance force in order to prevent occurrence of slip between rolls when a plate is engaged in indirect driving.

FIG. 6 is a cross-sectional view of an i-1 and i-stand four-high rolling mill showing a threaded state.

FIG. 7 is a cross-sectional view of the i-1 and i-stand 6-high rolling mills showing the threading state (i-stand is completely engaged, before i-stand is engaged).

FIG. 8 is a cross-sectional view of the i-1 and i-stand 6-high rolling mills showing the passing state (i-stand bite completed, i-stand bite before).

FIG. 9 is a cross-sectional view of the i-1 and i-stand 6-high rolling mills showing the threading state (at the moment when the i-stand is engaged).

FIG. 10 is a cross-sectional view of the i-1 and i-stand 6-high rolling mills showing the passing state (i-stand and i-stand bite completed).

FIG. 11 is an operation flow of a roll that restricts a sheet path of a rolled material during biting.

FIG. 12 is a cross-sectional view of the i-1 and i-stand 6-high rolling mill showing the state when the rolls are changed (i-stand and i-stand have been completely engaged).

FIG. 13 is an operation flow of a roll balance force during biting in an indirect drive mill.

FIG. 14 shows a hot rolling oil application mill i-1 and an i-stand 4.
Sectional rolling mill sectional view.

FIG. 15 is a pair cross mill.

FIG. 16 is a work roll cross mill.

FIG. 17 is a gourd-type roll mill.

FIG. 18 is a cluster mill.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rolled material, 2 ... Housing, 3 ... Work roll, 4 ... Intermediate roll, 5 ... Reinforcement roll, 6 ... Work roll chock,
7 ... middle roll chock, 8 ... reinforcement roll chock, 9
... Project block, 10 ... Work roll balance or roll bending, 11 ... Retraction jack, 12
... Pass line screw, 13 ... Load cell, 14 ... Incoming side plate guide, 15 ... Out side plate guide, 16 ... Stand looper, 17, 18 ... Roller roller, 19 ... Rolled material tip detector, 20 ... Out Side guide retract cylinder, 21
... Inlet guide retract cylinder, 22 ... Hot rolling oil spray nozzle for working roll, 23 ... Reinforcing roll drainer wiper, 24 ... Hot rolling oil for reinforcing roll or lubricating oil spray between rolls.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI B21B 27/02 B21B 27/02 A 27/10 27/10 B 28/04 28/04 A 29/00 29/00 C 39 / 14 39/14 B H 39/16 39/16 (56) References JP-A-5-305308 (JP, A) JP-A-8-276211 (JP, A) JP-A-6-320210 (JP, A) JP-A-8-132120 (JP, A) JP-A 54-84333 (JP, U) JP-A 61-195806 (JP, U) JP-A 57-152307 (JP, U) (58) (Int.Cl. ⁷ , DB name) B21B 13/14 B21B 1/26 B21B 27/02 B21B 27/10 B21B 28/04 B21B 29/00 B21B 39/14 B21B 39/16

Claims (17)

(57) [Claims] 1. A hot rolling equipment for rolling a hot plate by a plurality of rolling mills provided with work rolls, wherein the rolling mill provided with the work rolls has a function of guiding the progress of the plate. A pass guide member provided above and below the pass line, and a roller installed near the pass plate guide member and capable of moving up and down to a desired position with respect to a hot plate material guided by the pass plate guide member are provided. A hot rolling facility wherein the hot plate is guided between the work rolls. 2. The hot rolling equipment according to claim 1, wherein the roller is rotated by a driving device. 3. The rolling mill according to claim 1, wherein the rolling mill provided with the work rolls includes a detector for detecting the hot plate, and the hot plate is placed between the work rolls based on a result of the detector. A hot-rolling facility, comprising: a control device that raises and lowers the roller so as to guide the roller. 4. The rolling mill according to claim 1, wherein a rolling mill at a first stage among the plurality of rolling mills is the roller having a width smaller than a width of the hot plate material, and a rolling mill at a latter stage is smaller than the width of the hot plate material. A hot-rolling facility, characterized in that the hot-rolling equipment comprises the wide roller. 5. The hot rolling according to claim 1, wherein at least one of the plurality of rolling mills is a cluster mill that supports the work roll with a plurality of reinforcing rolls. Facility. 6. The hot rolling equipment according to claim 1, wherein the work rolls of at least one of the rolling mills constituting the rolling mill row are ground online by a roll grinding device. . 7. A work machine comprising a pair of small-diameter work rolls for rolling continuously fed plate material, a pair of intermediate rolls, a pair of reinforcing rolls, and a hydraulic device for applying hydraulic pressure to the work rolls. A rolling mill, wherein the rolling mill provided with the small-diameter work rolls, a guide plate provided above and below a pass line of the plate material to guide the progress of the plate material, and near the pass plate guide member A hot-rolling machine comprising a roller installed and capable of moving up and down to a desired position with respect to the hot-plate material guided by the passing-plate guide member, wherein the hot-plate material is guided between the work rolls. Facility. 8. The rolling mill according to claim 7, wherein the pair of intermediate rolls is configured to move along the roll axis direction of the intermediate roll. 9. The hydraulic device according to claim 7, wherein the hydraulic device for applying hydraulic pressure to the work roll controls a contact force between the work roll and the intermediate roll in accordance with the elevation of the roller. Hot rolling equipment characterized by being configured as described above. 10. The apparatus according to claim 7, wherein the plurality of rolling mills are configured to detect the hot plate and guide the hot plate between the work rolls based on a result of the detection device. A hot rolling facility comprising: a control device that moves a roller up and down and controls a contact force between the work roll and the intermediate roll. 11. The roll according to claim 7, wherein at least one of the plurality of rolling mills crosses the work roll and the intermediate roll as a pair, and changes a profile of a gap between the rolls to form a sheet crown. A hot rolling plant, characterized in that it is a rolling mill that can be changed. 12. The work roll, the intermediate roll, the reinforcing roll, or each of the work roll and the reinforcing roll according to claim 7, wherein a curve that is asymmetric with respect to a path center and symmetrical with respect to a vertical point. A hot-rolling plant, which is a rolling mill for applying and moving the rolls in the roll axis direction to change the gap profile between the rolls. 13. A four-high rolling mill comprising a pair of work rolls and a reinforcing roll, and a device for spraying hot rolling oil to the work rolls, wherein the rolling mill provided with the work rolls is adapted to advance the sheet material. A guide member provided above and below a pass line of the plate member for guiding the plate member, and a desired position with respect to a hot plate member provided near the guide member and guided by the guide member. And a roller capable of moving up and down to the work rolls, wherein the hot plate material is guided between the work rolls while spraying hot rolling oil on the work rolls. 14. The rolling mill according to claim 13, wherein the rolling mill crosses the work roll and the reinforcing roll as a pair, and changes a profile of a gap between the rolls so that a sheet crown can be changed. A hot rolling facility characterized by the following. 15. A rolling mill provided with a small-diameter work roll for rolling a hot plate material, wherein the rolling mill suppresses the hot plate material before the hot plate material reaches the small-diameter work roll. Rolling method, wherein the pressing roll is lowered to a desired position, and the pressing roll is raised when the tip of the hot plate material is bitten by the work roll. 16. A rolling mill provided with a small-diameter work roll for rolling a hot plate material and a hydraulic device for applying an oil pressure to the work roll, wherein the rolling machine is configured such that the hot plate material is applied to the small-diameter work roll. Before reaching, the holding roll for holding down the hot plate is lowered to a desired position, and when the leading end of the hot plate is bitten by the work roll, the hydraulic device interposes the roll between the work roll and the intermediate roll. A rolling method comprising: increasing a contact force, raising the roller after the work roll bites the hot plate material, and returning the hydraulic pressure of the hydraulic device to a normal value. 17. A rolling mill provided with a small-diameter work roll for rolling a hot plate material and a hydraulic device for applying hydraulic pressure to the work roll, wherein the rolling mill includes a holding roll for suppressing the hot plate material,
After passing directly below the holding roll, the holding roll is set at a position that restricts the sheet path so that a loop of the rolled material is not formed between the stands until it bites into the next stand,
A rolling method, wherein after the sheet material is bitten by the rolling mill, the rolled material is evacuated to a position where the rolled material does not contact the roll during the operation of the looper between stands.