1. A control apparatus of a rolling mill that outputs an operation instruction for controlling a prescribed target to be operated on a rolling mill, comprising: an input unit into which shape information pertaining to a shape of a rolled strip on a rolling mill entrance side or a rolling mill exit side is input; an operation instruction computing unit that computes an operation instruction amount used for changing lubricating coolant remaining on the rolled strip on the rolling mill entrance side with respect to a sheet width direction, on the basis of the shape information, such that the shape of the rolled strip on the rolling mill exit side approaches a target shape; and an output unit that outputs the operation instruction to the target to be operated.

2. The control apparatus of the rolling mill, according to claim 1, wherein, into the input unit, the shape of the rolled strip on the rolling mill exit side is input as the shape information, and the operation instruction computing unit computes the operation instruction amount used for changing a remaining amount of the lubricating coolant remaining on the rolled strip on the rolling mill entrance side, with respect to the sheet width direction, on the basis of the shape information, so as to reduce a deviation between the shape of the rolled strip on the rolling mill exit side and the target shape.

3. The control apparatus of the rolling mill, according to claim 1, wherein the target to be operated is a lubricating coolant sprayer, and the operation instruction computing unit modifies the lubricating coolant sprayed from the lubricating coolant sprayer onto the rolled strip according to the operation instruction, thereby changing a remaining amount of the lubricating coolant remaining on the rolled strip on the rolling mill entrance side, with respect to sheet width direction.

4. The control apparatus of the rolling mill, according to claim 1, wherein the target to be operated is a gas blower blowing gas, and the operation instruction computing unit applies the gas to the lubricating coolant sprayed from the lubricating coolant sprayer, according to the operation instruction, thereby changing a remaining amount of the lubricating coolant remaining on the rolled strip on the rolling mill entrance side with respect to the sheet width direction.

5. The control apparatus of the rolling mill, according to claim 1, wherein the rolling mill is a tandem rolling mill comprising a plurality of stands, and a preceding stand of the tandem rolling mill performs shape control.

6. The control apparatus of the rolling mill, according to claim 1, wherein the rolling mill comprises at least one rolling mill stand comprising a plurality of rolls, and further comprises a roll feed device for supplying the rolled strip and a roll-up device for rolling up the rolled strip rolled by the rolling mill stand, and the apparatus further comprises: a speed controller that controls a roll speed at the rolling mill stand; and a roll gap controller that controls a vertical roll gap of the rolls.

7. A control method of a rolling mill, comprising: acquiring shape information pertaining to a shape of a rolled strip on a rolling mill entrance side or a rolling mill exit side; computing an operation instruction amount used for changing a remaining amount of lubricating coolant remaining on the rolled strip on the rolling mill entrance side with respect to a sheet width direction such that the shape of the rolled strip on the rolling mill exit side approaches a target shape, on the basis of the shape information; and outputting the operation instruction to a target to be operated.

8. A control apparatus of a rolling mill, substantially as herein described with reference to accompanying drawings.

9. A control method of a rolling mill, substantially as herein described with reference to accompanying drawings.

Background of the invention
(1) Field of the invention
The present invention relates to a control apparatus and a control method of a rolling mill, and more specifically to a control apparatus and a control method of a rolling mill that are suitable for shape control.
(2) Description of related art
In rolling mills, a prescribed shape of a rolled strip is required to be maintained on the rolling mill exit side. Thus, the shape has been controlled using mechanical means, such as a work roll bender, an intermediate roll bender, and leveling. In such control of the shape by mechanical means, the shape can be controlled according to linear to quartic functions. For instance, such a technique is described in JP-A-2005-144559.
Brief summary of the invention
Meanwhile, the shape has been controlled by regulating the flow rate of lubricating coolant (hereinafter referred to as coolant), which is sprayed onto work rolls for rolling lubrication and cooling, in the sheet width direction (hereinafter abbreviated to selective coolant application).
The selective coolant application refers to regulating thermal expansion due to processing heat in work-roll rolling by means of cooling with coolant, changing the surface shapes of work rolls, and performing rolling using the shapes to thereby control the shape of a rolled strip.
Here, the selective coolant application is effective as a shape control apparatus. However, the selective coolant application is a method of changing the thermal expansion amounts of work rolls. Accordingly, in some methods of using a rolling method or with some structures of rolling mills, shape control cannot be sufficiently performed. For instance, there is a problem in that this method is ineffective in the case of rolling a strip to be rolled with low processing heat due to rolling, or the case of including a mechanical configuration where entire work rolls are immersed in coolant.
It is an object of the present invention to provide a control apparatus and a control method of a rolling mill that can improve shape control accuracy.
In order to achieve the object, the present invention adopts a configuration that acquires actual shape information pertaining to the shape of a rolled strip on a rolling mill entrance side or a rolling mill exit side, computes an operation instruction amount used for changing a remaining amount of lubricating coolant remaining on the rolled strip on the rolling mill entrance side with respect to a sheet width direction such that the shape of the rolled strip on the rolling mill exit side approaches a target shape on the basis of the actual shape information, and outputs the operation instruction to a target to be operated.
The present invention can control the shape of a rolled strip by rolling phenomena due not only to thermal expansion of work rolls but also to change in friction coefficient, thereby realizing improvement in product accuracy and operational effectiveness.
Brief description of the several views of the drawing
Fig. 1 shows a rolling control method of the present invention;
Fig. 2 shows a control configuration of a single stand rolling mill;
Fig. 3 shows a selective coolant application device;
Fig. 4 shows an overview of remaining coolant;
Fig. 5 shows change in shape during coolant spraying;
Fig. 6 shows shape control by a bender;
Fig. 7 shows an overview of a remaining coolant regulator;
Fig. 8 shows an overview of an operation of controlling the shape by regulating a remaining amount of coolant;
Fig. 9 is an operational flow of shape control; and
Fig. 10 shows an overview of a remaining coolant regulator (Example 2).
Detailed description of the invention
First, an overview of embodiments of the present invention will be described. The length of remaining coolant, which occurs on a rolled strip on a rolling mill entrance side, is changed in sheet width direction. More specifically, on the rolling mill entrance side, coolant for both lubrication and cooling is sprayed onto work rolls. On the upper side of the rolled strip, the coolant is removed by falling downward from the ends of a sheet. Since the rolled strip is however flowing into the rolling mill at a certain speed, the coolant remains on the rolled strip. The coolant remaining on the rolled strip forms a lubricating film on the upper surface of the rolled strip. However, the amount of the film is different according to the remaining amount, which changes the friction coefficient between the work roll and the rolled strip during
the rolling process. Accordingly, the distribution of sheet thickness of the rolled strip varies on the rolling mill exit side, thus varying the shape.
In consideration of controlling the shape using this feature, the remaining amount of coolant on the rolling mill entrance side can be changed by the following (1) and (2). (1) Coolant nozzles are installed at positions apart from work rolls, and coolant is selectively sprayed on the rolled strip along the sheet width direction. (2) Air blowing nozzles are installed at positions apart from the work rolls, and the remaining coolant length is regulated, thereby changing the remaining amount of coolant in the sheet width direction. This can be realized without newly providing a machine in a housing of the rolling mill whose space is limited.
That is, although the description is partially redundant, the shape is controlled by changing the remaining amount of coolant on the rolled strip on the rolling mill entrance side. In an embodiment of change in remaining amount of coolant, coolant nozzles are arranged at sites apart from the rolling mill, and coolant is sprayed, thereby lengthening the remaining coolant at a certain point on the sheet in the sheet width direction. Here, it can be considered that the shape of the remaining coolant is controlled using air or the like. There is an advantage in that the arrangement can be realized easier than arrangement for selective coolant application on entrance side. Accordingly, existing facilities can be easily converted. Example 1
The case of applying the present invention to a single stand rolling mill will hereinafter be described.
Fig. 2 shows the configuration of a single stand rolling mill. The single stand rolling mill includes an entrance side TR (tension reel, hereinafter abbreviated to TR) 2 on the entrance side, and a exit side TR 3 on the exit side, with respect to the rolling direction of the rolling mill 1. A strip to be rolled, which is fed from the entrance side TR 2, is milled by the rolling mill 1, and subsequently rolled up on the exit side TR 3, thus performing rolling. The rolling mill 1 is provided with a roll gap controller 7 for allowing the sheet thickness of the rolled strip to be controlled by changing the roll gap, and a mill speed controller 4 for controlling the speed of the rolling mill 1. The entrance side TR 2 and the exit side TR 3 are driven by motors. The motors, and an entrance side TR controller 5 and an exit side TR controller 6, which are devices for driving the motors, are installed.
During rolling, a rolling speed setting device 10 outputs a speed instruction to the mill speed controller 4. The mill speed controller 4 performs control so as to maintain a uniform speed of the rolling mill 1. On the entrance and exit sides of the rolling mill 1, a tension is applied to the rolled strip, thereby performing rolling stably and effectively. An
entrance side tension setting device 11 and an exit side tension setting device 12 calculate the necessary tension therefor. On the basis of the entrance and exit side tension setting values calculated by the tension setting devices 11 and 12, current values for acquiring motor torques necessary to apply the setting tension to the rolled strip through the entrance side TR controller 5 and the exit side TR controller 6 on the entrance side TR 2 and the exit side TR 3 are calculated by an entrance side tension/current converter 15 and an exit side tension/current converter 16, and supplied to the entrance side TR controller 5 and the exit side TR controller 6, respectively. The entrance side TR controller 5 and the exit side TR controller 6 control the motor currents so as to attain given currents. A prescribed tension is applied to the rolled strip by means of the motor torques due to the motor currents that are supplied to the entrance side TR 2 and the exit sideTR3.
The tension/current converters 15 and 16 compute current setting values (motor torque setting values) for attaining a tension setting value on the basis of the models of a TR mechanical system and a TR controller. However, since the control models include errors, the tension setting value is corrected by entrance side tension control 13 and exit side tension control 14 using actual tensions measured by an entrance side tension meter 8 and an exit side tension meter 9 installed on the respective entrance and exit sides of the rolling mill 1. The corrected value is supplied to the tension/current converters 15 and 16, and the current values set in the entrance side TR controller 5 and the exit side TR controller 6 are changed.
Since the sheet thickness of the rolled strip is important for product quality, the sheet thickness is controlled. The sheet thickness on the exit side of the rolling mill 1 is controlled by an exit side sheet thickness controller 18 operating the roll gap of the rolling mill 1 using the roll gap controller 7 on the basis of an actual sheet thickness detected by an exit side sheet thickness meter 17.
With reference to Fig. 2, the description is made on the case of rolling from the entrance side TR 2 to the exit side TR 3, from the left to the right in the drawing, (hereinafter abbreviated to a rolling direction). However, a single stand rolling mill is capable of rolling in the reverse direction (from the right to the left). Although it depends on product specifications, operation methods that roll a rolled strip multiple times to acquire a desired sheet thickness are typically adopted. Also in a single stand rolling mill, an operation is performed as follows: that is, first rolling is performed from the left to the right, and a rolled strip having been on the entrance side TR is rolled up by the exit side TR; and, in a second rolling, the rolling direction is changed to the direction from right to the left, and the rolled strip on the exit side TR is rolled up by the entrance side TR. These processes are repeated certain times, thereby allowing a desired
sheet thickness of a product to be achieved.
A coolant sprayer 50, which is a control apparatus for securing lubrication between the rolled strip and the work rolls and changing the thermal expansion amount of the work rolls due to rolling process heat in the sheet width direction to control the shape of the rolled strip on the rolling mill exit side, is installed on the rolling mill entrance side. In the coolant sprayer 50, the coolant spray rate is regulated in the sheet width direction by means of shape control 21 for maintaining the actual shape detected by an exit side shape meter 200 installed on the rolling mill exit side to a target shape.
In addition to the coolant, means for controlling the shape of the rolled strip by mechanically changing deflection of the work rolls, such as a work roll bender, an intermediate roll bender, and leveling, may be adopted as shape control apparatuses. The description thereof is omitted in this specification. The shape is represented by the distribution of elongation of the rolled strip in the sheet width direction. Both the work roll bender and the intermediate roll bender apply forces to the opposite ends of the rolls to bend the rolls, thereby changing the shape in the sheet width direction generally according to a quadric or quartic function. The leveling changes the roll gaps at the opposite ends of the rolls, and changes the shape according to a linear function.
Meanwhile, according to the selective coolant application, the coolant sprayer 50 includes a plurality of spray nozzles 51 as shown in Fig. 3. Coolant, which is supplied from a coolant supplier 52 through coolant piping 53 for lubricating and cooling during rolling, is selectively supplied onto the surfaces of the work rolls in the sheet width direction.
Subsequently, the coolant 60 sprayed onto the lower work roll 122, as it is, falls down to the bottom of the rolling mill. Meanwhile, although the coolant sprayed onto the upper work roll 121 falls down from the ends of the rolled strip 123 in the sheet width direction, the coolant is left to become remaining coolant 61 on the rolled strip 123 until falling from the ends of the sheet according to the rate of sprayed coolant. The rolled strip 123 moves at a high speed (about several hundred meters/min.) relative to the rolling mill. Accordingly, the coolant remaining on the rolled strip 123 maintains its length so as to correspond to the amount of remaining coolant and the moving speed of the rolled strip 123 on the rolling mill entrance side. This length is the remaining coolant length 62.
Fig. 4 shows a state of the coolant sprayed from the spray nozzle 51. The coolant sprayed onto the work roll reduces the temperature of the work roll and suppress the thermal expansion due to the rolling process, and adheres onto the surface of the work roll and intervenes between the rolled strip and the work roll, thereby contributing to lubrication during
the rolling process.
Meanwhile, the coolant remaining on the upper surface of the rolled strip adheres to the surface of the rolled strip and intervenes between the rolled strip and the work roll, thereby contributing to lubrication during the rolling process. The coolant used for rolling is in a state of emulsion of oil and water mixed together, where oil particles are suspended in the water. In this state, oil particles adhering onto the rolled strip are conveyed to a contact part between the rolled strip and the work roll, thereby contributing to lubrication during rolling. Accordingly, the longer the remaining coolant length 62 on the upper surface of the rolled strip, the time of contact between the coolant and the rolled strip becomes longer. This allows the amount of oil adhering to the surface of the rolled strip to be increased with the remaining coolant length, thereby increasing contribution to lubrication and reducing the friction coefficient.
The shape of the rolled strip is the difference of elongation rates in the sheet width direction, and is formed by variation in distribution of sheet thickness in the sheet width direction on the rolling mill exit side due to rolling. The sheet thickness on the rolling mill exit side varies owing to the gap between the upper and lower work rolls, the tension applied to the rolled strip, the friction coefficient and the like. The selective coolant application regulates the rate of coolant sprayed onto (the work roll (upper) 121 and the work roll (lower) 122) work rolls 120 with respect to the sheet width direction, and changes the distribution of the sheet thickness on the ongoing side in the sheet width direction by changing the gap between the upper and lower work rolls due to change in thermal expansion of the work rolls 120 and by changing the friction coefficient, thereby changing the shape.
The coolant spraying effects on the shape are analyzed as follows. Spraying coolant  reduction in friction coefficient (viewpoint of the friction coefficient)
 reduction in load
 thin sheet thickness on the exit side
 elongation of the shape (increase in elongation rate) Spraying coolant  reduction in thermal expansion amount (viewpoint of cooling the work rolls)
 increase in sheet thickness
 swelling shape (reduction in elongation rate) That is, the course of change in shape is different, depending on whether the coolant spraying is regarded as variation in friction coefficient or variation in thermal expansion amount. In actuality, according to an examination on variation in shape on the rolling mill exit
side during spraying coolant, as shown in Fig. 5, there is a tendency to elongation (increase in elongation rate) of the shape immediately after spraying coolant. However, the tendency changes to a swelling tendency (reduction in elongation rate). This is because the friction coefficient starts to change immediately after spraying but reduction in thermal expansion amounts of the work rolls requires time.
In many cases of shape control using selective coolant application, a control method is adopted that sprays coolant on areas on the work rolls corresponding to parts where the shape elongates because it is considered that effects of variation in thermal expansion amounts of work rolls due to spraying the coolant are dominant. In cases of low heat generation due to rolling and with little thermal expansion, it is considered that effects due to variation in friction coefficient are dominant; it can thus be considered that a control method is adopted that stops spraying coolant on areas on work rolls corresponding to parts where the shape elongates.
In the case of performing selective coolant application control, the coolant sprayers 50 are required to be installed adjacent to the work rolls. The coolant spray nozzles 51 are typically installed at intervals of 50 mm in the sheet width direction. Valves are installed to allow independently spraying the coolant and stopping the spraying. This requires piping for causing the coolant to flow therethrough, and air piping for opening and closing the valves (in the case of air valves) or electric wiring (in the case of electromagnetic valves). Thus, these components are sometimes incapable of being installed owing to the mechanical structure of a rolling mill (e.g., a Sendzimir rolling mill). In the case of trying to newly install selective coolant application device on a rolling mill having already been installed, the device is sometimes incapable of being installed because space is insufficient. In these cases, installment of a selective coolant device is sometimes discarded and the shape cannot be controlled by coolant.
In the case of shape control using a bender, if an M-shape occurs as shown in Fig. 6, an attempt is made to correct the shape using the difference in change of the shapes of the intermediate roll and the work roll due to a bender operation. For instance, the intermediate roll bender is operated in the direction to decrease the gap between the upper and lower work rolls in order to increase bending, and the work roll bender having a larger effect on the ends of the sheets is operated in the direction to increase the gap between the upper and lower rolls in order to reduce bending.. However, in the case where the effects of the intermediate roll and the work roll on the shape are equivalent to each other, what is called a "compulsory parting phenomenon" occurs in which the intermediate roll bender operates to the maximum or the work
roll bender operates to the minimum without correcting the M-shape.
In such a case, some benders cannot correct the M-shape and thereby require shape control by coolant. Thus, even with rolling facilities incapable of being provided with a selective coolant application device, only if the remaining amount of coolant on the rolled strip can be changed, the shape can be changed by coolant.
It is suffice that a method of changing the remaining amount of coolant installs the coolant sprayers (coolant nozzles) 50 on the rolling mill entrance side to spray coolant on a rolled strip, thereby changing the remaining amount of coolant with respect to the sheet width direction. Fig. 1 shows a configuration in this case. A part in the sheet width direction where the remaining coolant is to be lengthen by the shape control is identified from the actual shape measured by the exit side shape meter 200 of the rolling mill, and the nozzle of the remaining coolant regulator 202 at the part is turned into the spraying state to thereby spray the coolant on the upper part of the rolled strip on the rolling mill entrance side. This allows the remaining coolant length to be increased. Even in the case without mechanical installation space adjacent to the work rolls of the rolling mill, adoption of such a method allows the remaining coolant regulator 202 to be installed on the rolling mill entrance side having sufficient space. This enables the shape control by coolant to be applied.
Fig. 7 shows an overview of the remaining coolant regulator 202. The remaining coolant regulator 202 is installed at a position apart from the work rolls on the entrance side in the rolling direction. The remaining coolant regulator 202 includes coolant nozzles 202-1 to 202-k separated in the sheet width direction. The nozzles regulate spray flow rates by means of the respective coolant flow rate regulators 203-1 to 203-k. Here, coolant nozzles 202 and coolant flow rate regulators 203 are arranged in the sheet width direction. The exit side shape meter 200 is installed on the rolling mill exit side and can measure the actual shape. Here, the case of k = 8 is discussed for the sake of simplicity. The exit side shape meter 200 supports eight measurement zones and can measures the shape of each zone. The coolant nozzle 202 and the remaining coolant regulator 203 are arranged in conformity to each measurement zone of the exit side shape meter 200.
Fig. 9 shows an operational flow of shape control 204. The shape control 204 receives the actual shape from the exit side shape meter 200, calculates a deviation from a predetermined target shape, and creates a shape deviation.
shape deviation = actual shape - target shape
The shape control using the remaining amount of coolant assumes that increase in remaining amount of coolant changes the shape of the part in the sheet width direction in the

elongation direction (increase in rolling reduction). Accordingly, a part having the minimum shape deviation (least elongated in the sheet width direction) is searched for, and the nozzle of the remaining coolant regulator 202 corresponding to this part is turned on (coolant spraying state).
For instance, in the case of the actual shape and the target shape as shown in Fig. 8, the shape deviation is the minimum at the position of the nozzle 202-2 of the remaining coolant regulator 202. Accordingly, the valve of the regulator 203-2 among the remaining coolant regulators 203 is turned on (spraying state), thereby spraying the coolant from the remaining coolant regulator 202-2. The sprayed coolant accumulates on the upper surface of the rolled strip as shown in Fig. 7, and the remaining amount of coolant at the part having the minimum shape deviation increases.
Here, it is assumed that the increase in remaining amount of coolant reduces the friction coefficient between the rolled strip and the work roll and, in turn, reduces the sheet thickness of the rolled strip on the exit side. However, it is also considered that the increase in remaining amount of coolant cools the rolled strip and, in turn, takes away the heat (or suppresses heat generation) during rolling, which changes the thermal expansion amounts of the work rolls, thereby changing the shape. In this case, the coolant is sprayed from the nozzle of the remaining coolant regulator for the part having the maximum shape deviation (202-k in the case of Fig. 8).
Even in the case without mechanical installation space adjacent to the work rolls of the rolling mill, adoption of such a method only requires installation of the remaining coolant regulator on the rolling mill entrance side having sufficient space, thereby allowing the shape control by coolant to be applied. Example 2
Example 1 adopts the remaining coolant length regulating device of spraying the coolant on the rolling mill entrance side. However, the shape control by coolant can also be realized by blowing air onto coolant remaining on the rolled strip to regulate the remaining amount of coolant.
Fig. 10 shows an overview of an operation of shape control of the remaining amount of coolant in this case. In this case, air supplied from an air supplier 54 is blown from the remaining coolant regulator 202. Air flow rate regulators 205 supply air supplied from the air supplier 54 through air piping 55, selectively in the sheet width direction, to nozzles 202-1 to 202-k of the remaining coolant regulators 202. The air blown from the nozzles of the remaining coolant regulators 202 is blown so as to push the coolant remaining on the upper
surface of the rolled strip, thereby regulating the remaining amount of coolant. In the case of the actual shape, target shape, and shape deviation shown in Fig. 8, the shape deviation at a part corresponding to the remaining coolant regulator 202-k (k = 8) is the maximum. Accordingly, the air flow rate regulator 205-k is turned on, thereby blowing air from the nozzle of the remaining coolant regulator 202-k. This changes the remaining amount of coolant as indicated by broken lines in Fig. 10 and reduces the remaining amount of coolant at the part having the maximum shape deviation. Accordingly, the sheet thickness on the exit side is increased (decrease in rolling reduction) and the elongation of the shape on the exit side is suppressed.
Here, it is assumed that reduction in remaining amount of coolant, in turn, reduces the shape deviation (change in remaining amount of coolant becomes change in friction coefficient, thereby changing the sheet thickness on the exit side). However, as described above, the shape control may be designed under assumption that change in remaining amount of coolant, in turn, changes the thermal expansion amount. Example 3
The examples are application to a single stand rolling mill. However, analogous means is applicable to a tandem rolling mill. In a tandem rolling mill, a selective coolant application device is typically installed on a final stand. However, adoption of this scheme allows the shape control by coolant to be used even at a preceding stand.
The method of regulating the remaining amount of coolant is not limited to the examples. Instead, any method can be adopted only if the method is capable of regulating the length of coolant, which remains on the upper surface of the rolled strip, with respect to the sheet width direction.
The present invention is applicable to control of a cold rolling mill and has no problem in actual application.

Claims:
1. A control apparatus of a rolling mill that outputs an operation instruction for controlling a prescribed target to be operated on a rolling mill, comprising: an input unit into which shape information pertaining to a shape of a rolled strip on a rolling mill entrance side or a rolling mill exit side is input; an operation instruction computing unit that computes an operation instruction amount used for changing lubricating coolant remaining on the rolled strip on the rolling mill entrance side with respect to a sheet width direction, on the basis of the shape information, such that the shape of the rolled strip on the rolling mill exit side approaches a target shape; and an output unit that outputs the operation instruction to the target to be operated.
2. The control apparatus of the rolling mill, according to claim 1, wherein, into the input unit, the shape of the rolled strip on the rolling mill exit side is input as the shape information, and the operation instruction computing unit computes the operation instruction amount used for changing a remaining amount of the lubricating coolant remaining on the rolled strip on the rolling mill entrance side, with respect to the sheet width direction, on the basis of the shape information, so as to reduce a deviation between the shape of the rolled strip on the rolling mill exit side and the target shape.
3. The control apparatus of the rolling mill, according to claim 1, wherein the target to be operated is a lubricating coolant sprayer, and the operation instruction computing unit modifies the lubricating coolant sprayed from the lubricating coolant sprayer onto the rolled strip according to the operation instruction, thereby changing a remaining amount of the lubricating coolant remaining on the rolled strip on the rolling mill entrance side, with respect to sheet width direction.
4. The control apparatus of the rolling mill, according to claim 1, wherein the target to be operated is a gas blower blowing gas, and the operation instruction computing unit applies the gas to the lubricating coolant sprayed from the lubricating coolant sprayer, according to the operation instruction, thereby changing a remaining amount of the lubricating coolant remaining on the rolled strip on the rolling mill entrance side with respect to the sheet width direction.
5. The control apparatus of the rolling mill, according to claim 1, wherein the rolling mill is a tandem rolling mill comprising a plurality of stands, and a preceding stand of the tandem rolling mill performs shape control.
6. The control apparatus of the rolling mill, according to claim 1, wherein the rolling mill comprises at least one rolling mill stand comprising a plurality of rolls, and further comprises a roll feed device for supplying the rolled strip and a roll-up device for rolling up the rolled strip rolled by the rolling mill stand, and the apparatus further comprises: a speed
controller that controls a roll speed at the rolling mill stand; and a roll gap controller that controls a vertical roll gap of the rolls.
7. A control method of a rolling mill, comprising: acquiring shape information
pertaining to a shape of a rolled strip on a rolling mill entrance side or a rolling mill exit side; computing an operation instruction amount used for changing a remaining amount of lubricating coolant remaining on the rolled strip on the rolling mill entrance side with respect to a sheet width direction such that the shape of the rolled strip on the rolling mill exit side approaches a target shape, on the basis of the shape information; and outputting the operation instruction to a target to be operated.
8. A control apparatus of a rolling mill, substantially as herein described with reference
to accompanying drawings.
9. A control method of a rolling mill, substantially as herein described with reference to accompanying drawings.