JP5616817B2 - Control device for hot rolling line - Google Patents

Description

  The present invention relates to a control device for a hot rolling line for producing metal products.

  Usually, a hot rolling line includes a heating furnace for heating a material to be rolled, a rough mill and a finishing mill for rolling the material to be rolled, a cooling device for cooling the material to be rolled, and a coil for the material to be rolled after rolling. It consists of a winder that winds up into a shape.

  The temperature history of the material to be rolled in the hot rolling line affects the material (mechanical properties) of the material to be rolled. In addition, the temperature of the material to be rolled during the rolling process changes the hardness of the material to be rolled and greatly affects the energy consumption required for the rolling process. For this reason, thermometers are arranged on the rough mill exit side, finish mill entry side, finish mill exit side, and the like of the hot rolling line to perform temperature measurement.

  In order to realize a desired material for the material to be rolled, the atmospheric temperature in the heating furnace is adjusted, and the material to be rolled is heated. The “extraction interval time” that represents the time from when one rolled material is extracted from the heating furnace until the next rolled material is extracted from the heating furnace is the operating condition and conveyance to achieve the maximum production pitch. It is determined from the prediction of the order. For example, the extraction interval time is determined so as to be the shortest interval at which the previously rolled material to be rolled and the subsequent rolled material do not collide on the hot rolling line.

  At this time, the material to be rolled is adjusted by adjusting the flow rate of the cooling spray (hereinafter referred to as “ISC”) installed between the rolling stands of the finishing mill and the rolling speed at which the material to be rolled is conveyed in the finishing mill. The target temperature of the material to be rolled on the finishing mill exit side is achieved and maintained over the entire length of the steel sheet.

  As described above, in the rolling process of the material to be rolled, a rolling schedule is planned in consideration of the material quality and the production amount, and the hot rolling line is controlled. The finishing mill outlet temperature (hereinafter referred to as “FDT”) needs to be controlled to a specified target value in order to secure the material of the product. In addition, on the finishing mill entry side, a phenomenon called “thermal rundown” occurs in which the temperature of the material to be rolled gradually decreases from the tip to the tail end of the material to be rolled. For this reason, in order to maintain the FDT at the target temperature over the entire length of the material to be rolled, it is necessary to adjust the ISC flow rate while accelerating the length of the material to be rolled.

  On the other hand, in order to increase the production amount of the product, it is necessary to shorten the extraction interval time of the material to be rolled. In order to shorten the extraction interval time, it is necessary to increase the rolling speed as long as the materials to be rolled do not collide on the hot rolling line. However, in general, when a metal material is deformed, even if the applied strain is the same, the stress (deformation resistance) required for deformation increases as the strain rate increases. For this reason, when the rolling speed is increased, the energy consumption required for rolling increases.

  Therefore, the rolling speed needs to be increased as much as possible in order to increase the production amount within the range where the FDT can be controlled to the target value, and needs to be decreased as much as possible in order to reduce the energy consumption amount.

  As a method of reducing energy consumption, energy consumption determined from the maximum rolling speed by the finishing mill and the temperature rise of the heating device for a hot rolling line in which a heating device is installed before the finishing mill. A method of determining the maximum rolling speed in the finishing mill and the heating amount of the heating device so as to minimize the amount has been proposed (see, for example, Patent Document 1). However, in the method proposed in Patent Document 1, no consideration is given to a decrease in production by lowering the rolling speed.

  In addition, as a method of predicting and calculating energy consumption, the rolling required time for each material to be rolled is predicted based on the actual data of the rolling process, and the rolling time for each material to be rolled is predicted from the slab data in the heating furnace. And the rolling electric power for every to-be-rolled material is estimated based on the amount of rolling processes, and the method of estimating the energy consumption of a rolling mill is proposed (for example, refer patent document 2). However, in the method proposed in Patent Document 2, the influence on the energy consumption due to the change in rolling speed is not considered.

Japanese Patent No. 3444267 Japanese Patent Laid-Open No. 64-15201

  Lowering the rolling speed to reduce energy consumption in the hot rolling line will increase the rolling time and may not be able to secure the extraction interval time necessary to achieve the target production volume. . On the other hand, although the target rolling time can be realized by increasing the rolling speed, there is a problem that the energy consumption increases.

  In view of the above problems, an object of the present invention is to provide a control device for a hot rolling line that achieves a target required rolling time and can suppress energy consumption.

According to one aspect of the present invention, there is provided a heating furnace and a control device for a hot rolling line including a finishing mill having a plurality of rolling stands arranged continuously and a cooling spray arranged between the rolling stands. (B) Target values for finishing mill outlet temperature, product thickness / width, and thickness / width / length of slab drawn into the heating furnace for multiple materials to be rolled It is, and based on the operating conditions including the number and total processing time of the rolled material obtained from operational information including the extraction temperature of the heating furnace, the sampling interval during which a plurality of material to be rolled is extracted from the heating furnace, previously And (b) rolling included in the extraction interval time and operation information , so as to calculate an interval so that the rolled material and the subsequent rolled material are not collided on the hot rolling line. by using the speed versus the one of the plurality of material to be rolled A target rolling time calculation device that calculates a target rolling time of the material to be rolled, (c) on the basis of the operational information, finish the necessary control reference value in order to achieve the thickness and the rolled material temperature as a target in the mill exit side As an initial value, an initial schedule calculation device for calculating the flow rate of the cooling spray and the speed pattern of the rolling speed at which the target rolled material is conveyed on the hot rolling line, and (d) to achieve the rolled material temperature When the flow rate of the cooling spray is corrected and the finishing mill outlet temperature cannot be set to the target value over the entire length of the target rolled material only by correcting the flow rate of the cooling spray, or the speed pattern is corrected. If you enter a speed change rate, and schedule correction device for correcting the velocity pattern by using the speed change ratio, a speed pattern that has been modified by (e) the schedule correction device The rolling time prediction calculation device that calculates the rolling time required for the target rolled material, and (f) calculates the speed change rate so that the rolling time is within the target rolling time, and schedules the calculated speed change rate In the rolling time adjusting device that outputs to the correction device, and (g) a plurality of arbitrary calculation points in the longitudinal direction of the target rolled material that are set in the hot rolling line, and a plurality of target points that perform temperature drop calculation Calculating the rolling power required for rolling the target rolling material proportional to the product of the speed of the rolling roll and the torque applied to the rolling roll using the speed pattern, and the energy consumption obtained by integrating the rolling power over time is minimized. An energy consumption adjustment device that newly calculates the speed change rate calculated to be and outputs the calculated speed change rate to the schedule correction device, and the required rolling time is the target rolling time The speed change rate is calculated by the rolling time adjustment device and the speed change rate is calculated by the energy consumption adjustment device so that the energy consumption is minimized, and the speed correction by the schedule correction device is repeated. A controller for determining the flow rate and speed pattern of the cooling spray is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the control apparatus of the hot rolling line which can implement | achieve the target required rolling time and can suppress energy consumption can be provided.

It is a schematic diagram which shows the structure of the control apparatus which concerns on the 1st Embodiment of this invention. It is a schematic diagram which shows the structural example of a hot rolling line. It is a flowchart for demonstrating the method of calculating a control reference value with the control apparatus which concerns on the 1st Embodiment of this invention. It is a schematic diagram which shows the structural example of the rolling mill periphery of the hot rolling line shown in FIG. It is a schematic diagram which shows the segment number and target point number of a to-be-rolled material. It is a conceptual diagram for demonstrating the determination method of the rolling time by the control apparatus which concerns on the 1st Embodiment of this invention. It is a schematic diagram which shows the change of the rolling power in the longitudinal direction of a material to be rolled. It is a flowchart for demonstrating the example of the convergence calculation at the time of changing the flow volume of a cooling spray by the control apparatus which concerns on the 1st Embodiment of this invention. It is a conceptual diagram for demonstrating the example of the speed correction method by the control apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart for demonstrating the method to determine extraction interval time by the control apparatus which concerns on the 2nd Embodiment of this invention. It is a schematic diagram which shows the structure of the control apparatus which concerns on the 4th Embodiment of this invention.

  Next, first to fourth embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. The following embodiments exemplify apparatuses and methods for embodying the technical idea of the present invention, and the embodiments of the present invention specify the structure, arrangement, etc. of the components as follows. It is not what you do. The embodiment of the present invention can be variously modified within the scope of the claims.

(First embodiment)
As shown in FIG. 1, the hot rolling line control device 10 according to the first embodiment of the present invention is a control device for the hot rolling line 20, and includes an operation condition processing device 11 and an extraction interval calculation device 12. , A target rolling time calculation device 13, an initial schedule calculation device 14, a schedule correction device 15, a rolling time prediction calculation device 16, a rolling time adjustment device 17, and an energy consumption adjustment device 18.

  The hot rolling line 20 controlled by the control device 10 includes a heating furnace and a finishing mill having a plurality of rolling stands arranged continuously and a cooling spray arranged between the plurality of rolling stands. Before describing the details of the control device 10, the hot rolling line 20 will be described with reference to FIG. The hot rolling line 20 shown in FIG. 2 includes a heating furnace 21, a rough mill 23, a finishing mill 26, and a winder 28. FIG. 2 shows a state in which the material to be rolled 100 is unloaded from the heating furnace 21.

  The material to be rolled 100 extracted from the heating furnace 21 is rolled by a reversible coarse mill 23. The roughing mill 23 usually has one to several rolling stands, and is rolled to the target intermediate bar plate thickness on the roughing mill exit side by passing the material 100 to the roughing mill 23 several times while reciprocating. Is done. The passage of the material to be rolled 100 through the rolling stand of the rough mill 23 is hereinafter referred to as “pass”.

  After being rolled by the coarse mill 23, the material 100 to be rolled is transported from the exit side of the coarse mill 23 to the entry side of the finish mill 26, for example, to a desired product thickness by the finish mill 26 comprising 5 to 7 rolling stands 260. Rolled. Between the rolling stands 260 of the finishing mill 26, a cooling spray (ISC) (not shown in FIG. 2) is installed.

  Further, as shown in FIG. 2, a coarse mill entry-side descaler 22 is arranged on the entry side of the coarse mill 23, and a finishing mill entry-side descaler 25 is arranged on the entry side of the finishing mill 26. Furthermore, a coil box 24 is arranged in the transfer table area between the rough mill 23 and the finishing mill 26.

  The material 100 to be rolled out from the finishing mill 26 is cooled by a cooling device 27 and then wound into a coil by a winder 28. The cooling device 27 is, for example, a water cooling device.

  A plurality of thermometers such as a coarse mill exit-side thermometer 291, a finishing mill entry-side thermometer 292, and a finishing mill exit-side thermometer 293 are arranged along the conveying direction of the material 100 to be rolled in the hot rolling line 20. Has been. With these thermometers, the temperature of the material 100 to be rolled at each position of the hot rolling line 20 is measured.

  Next, the control device 10 shown in FIG. 1 will be described.

  The operation condition processing device 11 outputs an operation condition PDI necessary for the extraction interval calculation device 12 and the initial schedule calculation device 14 from the input operation information. The operation information is input to the control device 10 as an operation command set to realize a desired production amount, input information designated by the operator, or the like. The operation information includes rolling process schedules for a plurality of rolled materials scheduled to be rolled. For example, FDT target values, product sheet thicknesses and sheet widths, and slab sheet thicknesses drawn into the heating furnace 21 Information including the plate width / length, the extraction temperature of the heating furnace 21 and the like.

The extraction interval calculation device 12 calculates the extraction interval time t _EX of the material to be rolled 100 that is sequentially extracted from the heating furnace 21 based on the operation conditions PDI such as the number of materials to be processed and the total processing time. The extraction interval time t _EX is a time from when one rolled material 100 is extracted from the heating furnace 21 to when the next rolled material 100 is extracted from the heating furnace 21.

The target rolling time calculation device 13 calculates the target rolling time t _Tar for the material 100 to be processed in the hot rolling line 20 by using the extraction interval time t _EX and information on the rolling speed included in the operation information. .

  The initial schedule calculation device 14 calculates the initial value SV0 of the control reference value necessary to achieve the target plate thickness and the material temperature to be rolled on the finishing mill delivery side based on the operation condition PDI. Specifically, the roll gap required for rolling, the flow rate of the cooling spray (ISC) arranged in the hot rolling line 20, and the rolling speed at which the material 100 to be processed is transported through the hot rolling line 20. Calculate the speed pattern.

The schedule correction device 15 corrects the flow rate of the ISC so as to achieve the target finishing mill outlet side temperature (target FDT) over the entire length of the material 100 to be rolled. Further, when the finishing mill outlet temperature (FDT) cannot be matched with the target value over the entire length only by correcting the ISC flow rate, the speed pattern of the rolling speed is corrected. Alternatively, when the speed change rate α _V related to the speed pattern of the rolling speed is input, the speed pattern of the rolling speed is corrected using the input speed change rate α _V.

  The corrected ISC flow rate and speed pattern are output to the hot rolling line 20 as a control reference value SV for controlling the hot rolling line 20. For example, the ISC flow rate is output to an actuator that controls the flow rate by adjusting an ISC valve disposed in the hot rolling line 20, and the speed pattern is applied to a drive that drives a roll of a rolling stand 260 of the finishing mill 26. Is output.

Rolling time prediction calculating unit 16, using the velocity pattern included in the control reference value SV determined by the schedule modification apparatus 15, calculates the rolling time required t _rm of the rolled material 100.

Rolling time adjustment device 17 compares the rolling and the time required t _rm calculated by the rolling time predicting calculation unit 16, a target rolling time calculated by the target rolling time calculation unit 13 t _Tar. Then, the speed change rate α _V of the rolling speed is calculated so that the rolling required time _trm is within the target rolling time t _Tar . The calculated speed change rate α _V is output to the schedule correction device 15.

The energy consumption adjustment device 18 calculates the rolling power at a plurality of calculation points set in the hot rolling line 20 based on the speed pattern calculated by the schedule correction device 15, and integrates the calculated rolling power with time integration. To calculate energy consumption. The rolling power is calculated using a driving current of a motor that drives the rolling stand. When the energy consumption can be reduced, the energy consumption adjustment device 18 calculates the speed change rate α _V so as to minimize the energy consumption, and outputs it to the schedule correction device 15.

As described above, the control device 10 shown in FIG. 1, the rolling required time t _rm to minimize the energy consumption under the condition that within the target rolling time t _Tar, flow and hot rolling of ISC The speed pattern of the rolling speed of the material to be rolled 100 conveyed through the line 20 is determined.

  Below, the example of the method of controlling the hot rolling line 20 with the control apparatus 10 shown in FIG. 1 is demonstrated with reference to FIG. In FIG. 3, a flowchart 31 on the left side shows a rolling campaign calculation method. The “rolling campaign” is a unit of a material to be rolled that is scheduled to be rolled continuously, for example, a unit of a material to be rolled that is scheduled to be rolled before the roll of the hot rolling line 20 is replaced. is there. The flowchart 32 on the right side of FIG. 3 shows a calculation method of the target rolled material 100 [a], which is one of a plurality of rolled materials scheduled to be processed in the hot rolling line 20. The target rolled material 100 [a] is an ISC flow rate and speed pattern creation target, and is a rolled material that is scheduled to be rolled a-th.

  First, the process shown in the flowchart 31 will be described.

  In step S <b> 311, the operation condition PDI in the rolling campaign sent from the operation condition processing device 11 is input to the extraction interval calculation device 12.

In step S312, the extraction interval calculation device 12 calculates the extraction interval time t _EX [a] based on the operation condition PDI. This extraction interval time t _EX [a] is determined on the basis of the rolling campaign and heating furnace operating conditions, not for each material to be rolled. Note that the symbol [a] represents a numerical value related to the target rolled material 100 [a] (the same applies hereinafter).

For example, when the heating time in the heating furnace 21 is determined, the extraction interval time t _EX [a] is predicted to be drawn or drawn into the heating time and the heating furnace 21 of the material to be rolled 100. It is determined by the time.

Using the rolling campaign or the number P of _unrolled workpieces 100 and the target time required to roll all these rolled materials (hereinafter referred to as “target total rolling time”) t _Tgt . Thus, the extraction interval time t _EX [a] of the target workpiece 100 [a] is calculated by the following equation (1):

t _EX [a] = t _Tgt / P + f (FDTa [a], SGF [a], dh [a], l [a]) (1)

The second term on the right side of Equation (1) is a correction term, and is expressed as a function of the target finishing mill outlet temperature FDTa, the material type division SGF, the total reduction amount dh, and the rolling material length l. These numerical values are determined in advance.

Since the sum of the extraction interval times t _EX [a] needs to be equal to the target total rolling time t _Tgt , the following relations (2) and (3) are satisfied:

t _Tgt = _{Σt EX} [a] (2)
Σ (f (FDTa [a], SGF [a], dh [a], l [a])) = 0 (3)

In equations (2) and (3), Σ represents the sum from a = 1 to P.

Next, in step S313, the target rolling time calculation device 13 calculates the target rolling time t _Tar . The target rolling time t _Tar is calculated for the material to be rolled in the rolling campaign. Below, the calculation method of target rolling time t _Tar is shown.

The target rolling time t _Tar [a] of the target rolled material 100 [a] scheduled to be rolled a-th is not caught up with the a + 1-th rolled material 100 [a + 1] scheduled to be rolled next. Need to be rolled into. Accordingly, the target rolling time t _Tar [a] of the target rolled material 100 [a] is calculated by the following equation (4):

t _Tar [a] = t _EX [a + 1] + t _R [a + 1] (4)

In Expression (4), t _R [a] is the arrival time at the finish mill rolling start position of the target workpiece 100 [a]. The “finish mill rolling start position arrival time” is the time from when the target rolled material 100 [a] is extracted from the heating furnace 21 until the finish mill rolling start position is reached. The “finish mill rolling start position” can be arbitrarily set. For example, when the target rolled material 100 [a] is too close to the preceding previous rolled material 100 [a-1], the target rolled material is rolled. The material 100 [a] is set at a standby position.

The finishing mill rolling start position arrival time t _R [a] is expressed by the following equation (5):

t _R [a] = Σt _Rr [n] [a] + Σt _T [n] [a] + t _TFM [a] (5)

In Equation (5), Σ represents the sum from n = 1 to N _R. N _R is the number of rolling stands of the coarse mill 23. Further, t _Rr [n] is the time required for rolling at the n-th rolling stand of the rough mill 23, t _T [n] is the n-th stand entrance side transport time of the rough mill 23, and t _TFM is the final stand of the rough mill 23. This is the delivery time on the delivery side.

The finishing mill rolling start position is located on the upstream side of the hot rolling line 20 with respect to the finishing mill 26. For this reason, the speed at the time of rolling by the rough mill 23 that is an upstream process from the finishing mill rolling start position and the speed at which the material to be rolled are conveyed are not affected by the temperature control. Accordingly, the finishing mill rolling start position arrival time t _R [a] can be accurately predicted at this stage.

When the next material can be caught up during the rolling by the rough mill 23, it is necessary to change the rolling speed of the target material 100 [a] or the next material. For this reason, in the m-th rolling stand of the coarse mill 23, the condition of the following formula (6) needs to be satisfied:

_{Σ m t Rr [n] [} a] + Σ m t T [n] [a] ≦ t EX [a + 1] + Σ m-1 t Rr [n] [a + 1] + Σ m t T [n] [ a + 1] (6)

In Equation (6), Σ _m represents the sum from n = 1 to m, and Σ _m−1 represents the sum from n = 1 to m−1.

The extraction interval time t _EX [a] and the finishing mill rolling start position arrival time t _R [a] of each material 100 calculated so far are the required rolling time _trm and the target rolling time by the rolling time adjusting device 17. Used for comparison with t _Tar .

  Thus, the process illustrated in the flowchart 31 ends.

As described above, the target rolling time t _Tar is calculated in advance at the timing when the calculation shown in the flowchart 31 for the rolling campaign is performed. Further, when the rolling speed and the extraction interval time t _EX are changed by manual intervention by the operator, the target rolling time t _Tar needs to be recalculated.

  Next, the process shown in the flowchart 32 for the target workpiece 100 [a] will be described. The timing for executing the calculation for the target rolled material 100 [a] is performed at an arbitrary timing before the target rolled material 100 [a] is rolled.

  In step S321, the initial schedule calculation device 14 receives the operation condition PDI of the target workpiece 100 [a] transmitted from the operation condition processing device 11.

  In step S322, the initial schedule calculation device 14 performs schedule calculation based on the operation condition PDI. In the schedule calculation, in order to achieve the target sheet thickness and rolled material temperature on the finish mill delivery side, the roll gap and cooling required for rolling are determined based on the operating conditions of the hot rolling line 20 and operator input data. The flow rate of water and the speed pattern during rolling of the finish mill 26 of the material 100 are determined.

  FIG. 4 shows a finishing mill schedule calculation area that is a target of schedule calculation related to the finishing mill 26. In order to predict the temperature of the target material to be rolled 100 [a], the finishing mill exit side temperature is measured from the finishing mill entry side thermometer 292 in consideration of the flow rate of the ISC 265 installed between the stands of the finishing mill 26. Up to a total of 293, the temperature drop calculation is performed by the initial schedule calculation device 14.

  At this time, the flow rate of the ISC 265 necessary to achieve the target FDT differs at each longitudinal value of the target rolled material 100 [a] due to thermal rundown or acceleration / deceleration of the target rolled material 100 [a]. For this reason, it is necessary to perform a temperature drop calculation for every arbitrary calculation point in the longitudinal direction of the target workpiece 100 [a]. This calculation point is hereinafter referred to as “target point”. 5A to 5C show the segment numbers and target point numbers of the material 100 to be rolled.

  Fig.5 (a) has shown the to-be-rolled material 100, the figure right end is a front-end | tip, and the figure left end is a tail end. In order to clearly show an arbitrary point in the longitudinal direction of the material 100 to be rolled, a unit obtained by virtually dividing the material 100 to be rolled at equal intervals is called a segment. FIG. 5B shows a segment of the material 100 to be rolled. For simplicity, the segment numbers are assigned in order from the tip of the material to be rolled 100 to the tail. FIG. 5C shows the target point number. For the target points 0 to M, important points in the rolling process are selected. The target point is set at, for example, a biting point, an intermediate point at which the rolling speed is maximized, or a tail end point at which the temperature is lowered.

  In steps S323 to S325 of FIG. 3, the schedule correction device 15 calculates the flow rate and speed pattern of the ISC 265 as follows so that the target FDT can be achieved over the entire length of the target rolled material 100 [a].

  In step S323, the schedule correction device 15 calculates the flow rate of the ISC 265 so as to achieve the target FDT. Therefore, the temperature drop calculation is performed by changing the flow rate of the ISC 265, and the convergence calculation is performed so that the calculated FDT matches the target FDT. Details of the convergence calculation when the flow rate of the ISC 265 is changed will be described later.

  When the target FDT cannot be achieved even when the flow rate of ISC265 obtained by the convergence calculation is applied, it is necessary to change the rolling speed pattern to achieve the target FDT. Specifically, when the target FDT cannot be achieved even at one of the target points when the flow rate of the ISC 265 is corrected, the schedule correction device 15 performs the entire length of the target rolled material 100 [a] in step S324. It is determined that the target FDT cannot be achieved. In this case, in order to change the speed pattern and achieve the target FDT, in step S325, the schedule correction device 15 corrects the speed pattern of the rolling speed. Details of the speed pattern correction method will be described later.

  After correcting the speed pattern, the process returns to step S323, and the flow rate of the ISC 265 is calculated again using the corrected speed pattern. Steps S323 to S325 are repeated to determine a speed pattern that achieves the target FDT over the entire length of the target rolled material 100 [a].

Next, in step S326, the rolling time prediction calculation device 16 calculates the required rolling time _trm [a] of the target rolled material 100 [a]. The rolling time t _rm [a] is expressed by the following equation (7):

t _rm [a] = t _R [a] + t _F [a] (7)

In Formula (7), t _F [a] is the rolling time required from the finish mill rolling start position until the tail end of the target rolled material 100 [a] exits the finish mill 26 (hereinafter referred to as “finish mill rolling time”). ").

In step S326, the required rolling time t _rm [a] is calculated from the speed pattern corrected by the schedule correction device 15. As shown in Expression (7), the sum of the finishing mill rolling start position arrival time t _R [a] calculated by Expression (5) and the finishing mill rolling time t _F [a] is the required rolling time t _rm [a ].

Next, in steps S327 to S329, the rolling time adjusting device 17 calculates the speed change rate α _V so that the required rolling time t _rm [a] is within the target rolling time t _Tar [a].

In step S327, it is determined whether or not the required rolling time _trm [a] calculated in step S326 is within the target rolling time t _Tar [a]. FIG. 6A to FIG. 6C show conceptual diagrams of a method for determining the rolling time.

FIG. 6 (a) shows the state of the timing when the target workpiece 100 [a] is extracted from the heating furnace 21. FIG. 6B shows the state of the timing when the target material to be rolled 100 [a] reaches the finishing mill rolling start position after the finishing mill rolling start position arrival time t _R [a]. At this time, the extraction interval time t _EX [a + 1] of the material to be rolled 100 [a + 1] processed next to the object to-be-rolled material 100 [a] is the same as that of the target material to be rolled 100 [a]. If it is smaller than the extraction interval time t _EX [a], the material to be rolled 100 [a + 1] has already been extracted from the heating furnace 21. FIG. 6C shows a state at the timing when the finish mill rolling of the target rolled material 100 [a] is completed after the finish mill rolling time t _F [a].

In order for the rolling required time t _rm [a] to be within the target FDT, the target material to be rolled 100 [a] needs to reach the finish mill rolling start position without being caught up by the next material. Therefore, the sum of the finishing mill rolling start position arrival time t _R [a] and the finishing mill rolling time t _F [a] of the target rolled material 100 [a] is the next material extraction interval time t _EX [a + 1]. And the finishing mill rolling start position arrival time t _R [a + 1]. That is, the following equation (8) may be satisfied:

t _R [a] + t _F [a] (cur) ≦ t _EX [a + 1] + t _R [a + 1] −deltaM (8)

In the equation (8), deltaM indicates a margin time, and is a fixed value determined in advance in order to prevent the materials to be rolled from getting too close in the hot rolling line 20. T _F [a] (cur) is the current value of the finishing mill rolling time t _F [a].

  When the condition of Expression (8) is satisfied, the process proceeds to step S330, and energy consumption calculation is performed.

If the condition of Expression (8) is not satisfied, it is determined in step S328 in FIG. 3 whether or not the flow rate and speed pattern of the ISC 265 can be changed. If it can be changed, the speed change rate α _V is calculated in step S329. Whether the flow rate and speed pattern of the ISC 265 can be changed is determined based on the maximum flow rate of the ISC 265, the ability of the motor that drives the rolling stand 260, and the like.

On the other hand, if the flow rate and speed pattern of the ISC 265 cannot be changed in step S328, the rolling time adjusting device 17 determines that the finishing mill rolling time t _F [a] cannot be changed any more. In that case, the speed pattern is not corrected, and the process proceeds to step S330.

In the speed change rate calculation in step S329 described above, the speed change rate α _V is calculated for the rolling speed in the finishing mill 26 so as to satisfy Expression (8). The new finishing mill rolling time t _F [a] (new) is calculated as in equation (9) below:

t _F [a] (new) = t _EX [a + 1] + t _R [a + 1] −t _R [a] −delta M (9)

The rolling time adjusting device 17 compares the current value t _F [a] (cur) of the finishing mill rolling time with the target speed of the finishing mill rolling time, and determines the required speed change rate α _V by the following formula ( Calculate using 10):

α _V = C ₁ × (t _F [a] (cur) / t _F [a] (new)) (10)

In Expression (10), C ₁ is a constant determined empirically and is a fixed value or a table value recorded in a database or the like.

After calculating the speed change rate α _V of the finishing mill speed in step S329, using the speed change rate α _V , the speed pattern is corrected in step S325, and the flow rate correction calculation of ISC 265 is performed again in step S323. . Thereby, the speed pattern and the flow rate of the ISC 265 are corrected so as to achieve the target FDT.

If the required rolling time t _rm [a] is within the target rolling time t _Tar [a] in step S327, or if the flow rate and speed pattern of the ISC 265 cannot be changed any more in step S328, the process proceeds to step S330. The energy consumption required for rolling the target workpiece 100 [a] is calculated.

In steps S330 to S333, the energy consumption adjustment device 18 calculates the energy consumption and calculates the speed change rate α _V necessary for minimizing the energy consumption.

  In the calculation of energy consumption in step S330, the rolling power (kW) at the target point is calculated using the speed pattern calculated by the schedule correction device 15. The energy consumption adjusting device 18 uses the calculated rolling power until the target rolled material 100 [a] is bitten until the tail end is removed, that is, the entire length of the target rolled material 100 [a]. Calculate energy consumption (kWh).

The energy consumption amount E _P required for rolling the target workpiece 100 [a] is expressed by the following equation (11):

E _P = ΣE j = Σ {(1/3600) × ∫P _Wj (t) dt (11)

In equation (11), ∫dt represents the time integration from t = 0 to s. Here, s (sec) is a rolling time. Further, Σ represents all the sums rolled by the coarse mill 23 or the finishing mill 26, and Ej (kWh) is an energy consumption amount in the j-th rolling. "Rolling j-th" means rolling in one rolling stand 1 to N _F paths roughing mill 23 (R [1] ~R [ N RP]) and the finishing mill 26.

The rolling power P _Wi (kW) at the target point i in equation (11) is calculated as follows:

P _Wi = (1000 × V _i × G _i ) / R _i + P _WLOSSi (12)

The rolling roll speed V _i (m / s), roll torque G _i (kNm), roll radius R _i (mm), and loss power P _WLOSSi (kW) of _Expression (12) are values calculated by the schedule correction device 15. Alternatively, an empirically obtained value is used.

The rolling power P _Wi changes in proportion to the rolling roll speed V _i and the roll torque G _i as shown in the equation (12). Figure 7 shows the change in rolling power P _Wi of the material to be rolled longitudinally. A thick line portion A in FIG. 7 indicates a change in the rolling power _PWi , and linear interpolation is performed between the target points. Areas E _{0 to} E ₄ indicate energy consumption amounts between the target points. The area shown by hatching in FIG. 7 is the energy consumption. That is, the energy consumption is expressed by the following equation (13):

∫P _Wj (t) dt = Σ {(P _Wi + P _{W (i + 1)} ) × S _i / 2} (13)

In Expression (13), ∫dt represents the time integration from t = 0 to S, and Σ represents the total sum from i = 0 to M. M is the final target. Note that S _i indicates the rolling time between target points, and this S _i is calculated by different means depending on the speed change case. For example, when controlling the FDT using the ISC 265, the speed between the target points changes at a constant acceleration based on the designated acceleration. For this reason, the rolling time S _i is expressed by the following equation (14):

S _i = 2L _i / (V _{i + 1} + V _i ) (14)

In equation (14), L _i is the distance between each target point.

After calculating the energy consumption in step S330, in step S331, the energy consumption adjustment device 18 determines whether the energy consumption can be reduced. When the rolling time adjusting device 17 determines that the rolling time of the finishing mill cannot be changed any more, or when it is determined that the energy consumption cannot be reduced in the immediately preceding calculation of the energy consumption, the energy consumption adjusting device 18 Does not change the speed change rate α _V , the schedule correction device 15 outputs the control reference value SV in step S334, and the process ends.

On the other hand, if the energy consumption can be reduced, it is determined in step S332 whether the flow rate and speed pattern of the ISC 265 can be changed. If the flow rate or speed pattern of the ISC 265 can be changed, a new speed change rate α _V is calculated in step S333.

  Whether or not the energy consumption can be reduced is determined as follows, for example.

  Energy consumption generally decreases with decreasing rolling speed. This is because the rolling load is reduced because the strain rate required for rolling is reduced. On the other hand, when lubricating oil is applied between the roll of the rolling stand and the material to be rolled (lubricated rolling), the film thickness of the lubricating oil increases as the rolling speed increases, and the friction between the roll and the material to be rolled is increased. The calorific value due to the decrease is reduced, and the energy consumption of the hot rolling line is reduced. It is known that the influence of the former is usually large.

Therefore, the speed change rate α _V is determined in the direction of decreasing the rolling speed in the first energy consumption calculation, and in the second and subsequent calculations, the speed change rate α _V and the previous and current energy consumption calculation results are determined. To calculate the influence coefficient as follows.

In the first calculation of energy consumption, the speed change rate α _{V (old)} is determined in the direction of decreasing the rolling speed, as shown in Equation (15):

α _{V (old))} = C ₂ (15)

In Expression (15), C ₂ is a constant, such as a fixed value or a database table value. C2 is less than 1.0.

In the second and subsequent calculation of energy consumption, the speed change rate α _V , the previously calculated energy consumption E _{P (old)} and the current calculated energy consumption E _{P (new)} are compared, and the following formula is used: (16) Calculate the influence coefficient as shown in equation (17):

(∂E / ∂α _V ) _(new) = (E _{P (new)} −E _{P (old)} ) / (α _{V (old)} −1) (16)
α _{V (new)} = 1−C ₃ / (∂E / ∂α _V ) _(new) × | E _{P (new)} −E _{P (old)} | (17)

When the difference between the previous and current energy consumption is small, that is, when the following equation (18) is satisfied, or when the speed change rate α _V is small, that is, when the following equation (19) is satisfied, energy consumption It is determined that the amount cannot be reduced. In this case, when calculating the next energy consumption, in step S331, it is determined that the energy consumption cannot be reduced, and in step S334, the control reference value SV is output.

| E _{P (new)} −E _{P (old)} | <C ₄ (18)
| Α _{V (old)} −1 | <C ₅ (19)

Here, C ₃ , C ₄ , and C ₅ are empirically obtained constants such as fixed values or database table values.

Using the calculated speed change rate α _{V (new)} , the speed pattern is corrected in step S325, and the flow rate of the ISC 265 is corrected in step S323. As a result, the speed pattern and the flow rate of the ISC 265 are determined so that the FDT is maintained at the target temperature over the entire length of the material to be rolled 100 and the energy consumption is minimized under the conditions within the target rolling time t _Tar. Is done.

  Thus, the process illustrated in the flowchart 32 ends.

Here, an example of the convergence calculation when the flow rate of the ISC 265 is changed in step S323 of FIG. 3 will be described with reference to FIG. In the flowchart of FIG. 8, i indicates a target point number, ns is the smallest target point number to be calculated, and ne is the largest number. Moreover, j represents the number of rolling stands 260 of the finishing mill 26, the final rolling stand number is N _F. In steps S600 to S613 shown in FIG. 8, the flow rate of the ISC 265 is changed so that the FDT is the target FDT for all of the target point numbers ns to ne.

In step S601, the data of the target point i necessary for FDT calculation is read. The necessary data are at least the finishing mill entry side temperature FET _i ^cal , the dimensions of the material 100 to be rolled, and the temperature distribution. For these data, the calculated value is used when already calculated, and the predicted value is used when not calculated.

In steps S602 to S611, the flow rate of the ISC 265 is corrected so that the calculated temperature FDT _i ^cal is within the allowable value of the target FDT for each target point.

  First, in step S <b> 602, the initial schedule calculation device 14 performs a temperature drop calculation from the finishing mill entry-side thermometer position where the finishing mill entry-side thermometer 292 is disposed to the first rolling stand entry side of the finishing mill 26.

Next, in steps S603 to S607, from the first rolling stand 260 [1] of the finishing mill 26 to the final rolling stand 260 [N _F ], the rolling stand outlet side temperature SD _j T and the rolling stand inlet side temperature SE _j T Calculate The rolling stand exit side temperature SD _j T is calculated in consideration of the temperature drop amount that the material to be rolled 100 loses due to contact with the rolling stand 260, the processing heat generation accompanying the rolling, and the temperature rise amount due to frictional heat. In step S606, a temperature drop calculation is performed in consideration of the flow rate of the ISC 265 installed between the rolling stands of the finishing mill 26, heat loss due to heat transfer with the atmosphere, and radiation heat to the atmosphere.

In step S608, the calculated FDT temperature FDT _i ^{cal at} the finishing mill outlet thermometer position is calculated.

In step S609, it is determined whether or not the calculated temperature FDT _i ^cal is within the allowable value of the target FDT. If the calculated temperature FDT _i ^cal is within the allowable value of the target FDT, the process proceeds to step S612. If calculation has not been completed for all target points i, the target point number is incremented by one in step S613, and the process returns to step S602. If the calculation at all the target points i has been completed, the process is terminated.

On the other hand, if the calculated temperature FDT _i ^cal is not within the allowable value of the target FDT in step S609, the process proceeds to step S610, and it is determined whether the flow rate of the ISC 265 can be changed. Whether or not the flow rate of the ISC 265 can be changed depends on information indicating that the operating conditions and operator intervention cannot be changed, or whether or not the flow rate of the ISC 265 is within the limit. If the flow rate of the ISC 265 can be changed, the flow rate of the ISC 265 is changed within a changeable range in step S611. Thereafter, the process returns to step S602.

As described above, the calculated temperature FDT _i ^cal at each target point can be obtained by calculating the temperature drop from the finishing mill entry side thermometer position to the finishing mill exit side thermometer position.

Next, the speed correction method in step S325 of FIG. 3 will be described with reference to FIG. The speed correction method described below is a method of (1) applying the speed change rate α _V output from the rolling time adjusting device 17 or the energy consumption adjusting device 18, and checking the limit value of the rolling speed and the ISC 265 Check the limit value of the flow rate change amount.

A speed pattern SP1 indicated by a broken line in FIG. 9A is an example of a speed pattern before correction. The horizontal axis of Fig.9 (a) is a time axis, and has shown each timing. “FET _ON ” is the time for the tip of the material to be rolled 100 to pass through the finishing mill entry side thermometer 292, “FDT _ON ” is the time for the tail end of the material to be rolled 100 to pass through the finishing mill exit side thermometer 293, “ “FDT _OFF ” is the time for the tail end of the material to be rolled 100 to pass through the finishing mill exit side thermometer 293. “Coiler _ON ” is the time for the tip of the material to be rolled 100 to reach the winder 28.

First, the limit value of the rolling speed is checked. FIG. 9B shows speed patterns before and after applying the speed change rate α _V. When the speed change rate α _V is given, the speed change rate α _V is added to the predicted speed pattern to correct the speed pattern. A speed pattern SP2 indicated by a solid line in FIG. 9B is a speed pattern after the speed change rate α _V is applied.

Next, a limit value check of the change amount of the flow rate of the ISC 265 is performed. Here, using the speed pattern SP2 shown in FIG. 9B after applying the speed change rate α _V , the necessity of changing the speed pattern is confirmed under two conditions where the flow rate of the ISC 265 is maximized and minimized. Investigate. The necessity of changing the speed pattern can be checked by performing a temperature drop calculation for each segment from the finishing mill inlet side thermometer to the finishing mill outlet side thermometer. In FIG. 9C, the FDT _Tg indicated by the solid line is the target FDT, the FDT _MAX indicated by the broken line is the FDT calculation result under the condition that the flow rate of the ISC 265 is minimized, and the FDT _MIN is the maximum flow rate of the ISC 265. It is a calculation result of FDT under the conditions. The horizontal axis of FIG.9 (c) is a position from the front-end | tip of each segment. When the FDT _Tg is between FDT _MAX and FDT _MIN in each segment, the target FDT can be achieved over the entire length of the material 100 to be rolled by changing the flow rate of the ISC 265.

  Therefore, when there is a segment in which the FDT is lower than the target temperature under the condition that the flow rate of the ISC 265 is minimum, the speed of the speed pattern is increased so that all the segments achieve the target temperature.

  On the other hand, when there is a segment in which the FDT is higher than the target temperature under the condition where the flow rate of the ISC 265 is maximum, the speed of the speed pattern is reduced so that all segments achieve the target temperature.

Finally, the speed pattern is corrected so that the set rolling speed is within the limit value of the rolling speed. S _RMAX indicated by a broken line in FIG. _9D is an upper limit value of the rolling speed, and S _RMIN is a lower limit value of the rolling speed. The speed pattern is corrected so that the rolling speed until the material to be rolled 100 reaches the winder 28 does not exceed the sheet feed speed limit value determined from the idle rotation limit value of the winder 28. After reaching the winder 28, the speed pattern is corrected so as not to exceed the rolling speed limit value determined from the rotational speed limit value of the motor that drives the rolling stand. When the limit value of the speed at which the tail end of the material 100 to be rolled passes through the final rolling stand of the finishing mill 26 is determined, the speed pattern is corrected so as not to exceed the limit value.

  After the speed pattern is corrected by the above procedure, the speed pattern and the flow rate for achieving the target finishing mill outlet temperature over the entire length of the material 100 to be rolled are determined by performing the correction calculation of the flow rate of ISC 265 in step S323 of FIG. Is done.

As described above, according to the control device 10 according to the first embodiment of the present invention, the flow rate and the flow rate of the ISC 265 are controlled so that the finishing mill outlet temperature is maintained at the target temperature over the entire length of the material 100 to be rolled. The speed pattern of the rolled material 100 is determined, and the required rolling time _trm is accurately calculated from the determined speed pattern. The flow rate and speed pattern of the ISC 265 are corrected so that the calculated required rolling time is within the target rolling time t _Tar calculated based on the operation command related to the production amount and the input information of the operator.

Further, the rolling power at a plurality of target points is calculated using the speed pattern, and the energy consumption required for rolling is accurately calculated by time integration of the calculated rolling power. The flow rate and speed pattern of the ISC 265 are determined so as to minimize the energy consumption within the target rolling time t _Tar . Therefore, according to the control apparatus 10 shown in FIG. 1, the target rolling required time can be achieved and the energy consumption amount of the hot rolling line 20 can be suppressed.

(Second Embodiment)
FIG. 10 is a flowchart for explaining a method of determining the extraction interval time according to the second embodiment, which is performed by the control device 10 of the hot rolling line 20 shown in FIG.

  First, in step S1010, similarly to the method described with reference to the flowchart 31 of FIG. 3, calculation of a rolling campaign in which the total number of materials to be rolled 100 is P is executed. Subsequently, in steps S1020 to S1140, the following calculation is performed according to the rolling order on the rolled materials 100 [1] to 100 [P-1] in the rolling campaign.

In step S1030, the combination of the calculated extraction interval time t _EX [a] of the rolled material 100 [a] and the extracted interval time t _EX [a + 1] of the rolled material 100 [a + 1] The first extraction interval time combination is used.

In step S1040, the energy consumption adjusting device 18 uses the extraction interval times t _EX [a] and t _EX [a + 1] to roll the material 100 [a] and the material 100 [a + 1]. The energy consumption amounts E _P [a] and E _P [a + 1] are calculated by calculating the energy consumption amount described with reference to the flowchart 32 of FIG. Further, in step S1050, the sum P _tot of the energy consumption amount E _P [a] and the energy consumption amount E _P [a + 1] is calculated as follows:

P _tot = E _P [a] + E _P [a + 1] (20)

Subsequently, in step S1060, the extraction interval time t _EX [a] of the material to be rolled 100 [a] is decreased by the minute time Δt, and the extraction interval time t _EX [a + 1] of the material to be rolled 100 [a + 1] is reduced. ] Is increased by a minute time Δt:

t _EX ^SU [a] = t _EX [a] −Δt (21)
t _EX ^SU [a + 1] = t _EX [a + 1] + Δt (22)

Δt is, for example, about 1 to 5 (sec). A combination of the extraction interval times t _EX ^SU [a] and t _EX ^SU [a + 1] expressed in the equations (21) and (22) is defined as a second extraction interval time combination.

In step S1070, using the extraction interval times t _EX ^SU [a] and t _EX ^SU [a + 1], the flow chart 32 of FIG. 3 for the rolled material 100 [a] and the rolled material 100 [a + 1]. The energy consumption amount E _P ^SU [a] and E _P ^SU [a + 1] are calculated respectively by calculating the energy consumption amount described with reference to FIG. Further, in step S1080, the sum P _tot ^SU of the energy consumption amount E _P ^SU [a] and the energy consumption amount E _P ^SU [a + 1] is calculated:

P _tot ^SU = E _P ^SU [a] + E _P ^SU [a + 1] (23)

Next, in step S1090, the extraction interval time t _EX [a] of the material to be rolled 100 [a] is increased by a minute time Δt, and the extraction interval time t _EX [a + 1] of the material to be rolled 100 [a + 1] is increased. Is reduced by a minute time Δt: ^AD

t _EX ^AD [a] = t _EX [a] + Δt (24)
t _EX ^AD [a + 1] = t _EX [a + 1] −Δt (25)

A combination of the extraction interval times t _EX ^AD [a] and t _EX ^AD [a + 1] expressed in the equations (24) and (25) is defined as a third extraction interval time combination.

In step S1100, using the extraction interval times t _EX ^AD [a] and t _EX ^AD [a + 1], the material to be rolled 100 [a] and the material to be rolled 100 [a + 1] are flow charts 32 in FIG. The energy consumption amounts E _P ^AD [a] and E _P ^AD [a + 1] are calculated by calculating the energy consumption amount described with reference to FIG. Further, in step S1110, the sum P _tot ^AD of the energy consumption amount E _P ^AD [a] and the energy consumption amount E _P ^AD [a + 1] is calculated:

P _tot ^AD = E _P ^AD [a] + E _P ^AD [a + 1] (26)

In step S1120, first, second, and third extraction interval times that are combinations of extraction interval times when the energy consumption is the smallest among the sums P _tot , P _tot ^SU , and P _tot ^AD of energy consumption Use one of the combinations. The flow rate and speed pattern of the ISC 265 is determined using the extracted extraction interval time combination.

  Depending on the combination of extraction interval times, for example, the material 100 [a + 1] to be processed later stops in the hot rolling line 20 waiting for processing of the material 100 [a]. There is. There arises a problem that the material to be rolled 100 [a + 1] is cooled depending on the stop time. However, according to the method for determining the extraction interval time described above, an optimum combination of extraction interval times can be adopted.

  As described above, according to the method of determining the extraction interval time described with reference to FIG. 10, the total extraction interval time of all the scheduled rolling materials 100 does not change. For this reason, it is possible to determine the extraction interval time for reducing the total energy consumption of the scheduled material to be rolled while ensuring the production amount. Others are substantially the same as those in the first embodiment, and redundant description is omitted.

(Third embodiment)
In addition to equation (1), the extraction interval time t _EX can be calculated using the following equation (27):

t _EX = t _Tgt / P + χ (dh) (dh [a] −dh _AV ) + χ (l) (l [a] −l _AV ) +
χ (FDTa) (FDTa [a] −FDTa _AV ) + χ (Rp (GC)) (Rp (GC [a]) − Rp (GC) _AV ) (27)

In Expression (27), dh is the amount of reduction, l is the length of the material to be rolled, FDTa is the target FDT, and GC is the material type code. A value with a subscript AV for each item indicates an average value of all the materials to be rolled. The function Rp () calculates the number of rolling passes of the rough mill 23 according to the material type code GC.

Further, the function χ () is calculated by the change of the rolling required time t with respect to the change of each item x in the equation (27):

χ (x) = dt / dx (28)

That is, in the control device 10 according to the third embodiment of the present invention, the extraction interval calculation device 12 has the average reduction amount dh _AV and the average rolling material length l _AV of all the target rolled materials 100 [a] to be processed. The average finishing mill outlet temperature FDTa _AV is calculated. Then, the difference between the reduction amount dh [a] and the average reduction amount dh _AV of the target rolled material 100 [a], the difference between the rolling material length [a] and the average rolling material length l _AV , and the target finishing mill output The extraction interval time is calculated using the difference between the side temperature FDTa [a] and the average finishing mill outlet side temperature FDTa _AV .

According to said method, the influence on the reduction amount of each to-be-rolled material, the length of a rolled material, target FDT, and the extraction interval time of a material type code is considered. The sum of the extraction interval times t _EX represented by the equation (27) of the target rolled material 100 [a] (a = 1 to P) is the target total rolling time t _Tgt , and the equations (2) and (3) _Therefore , the extraction interval time t _EX that achieves the target total rolling time t _Tgt can be determined. Others are substantially the same as those in the first embodiment, and redundant description is omitted.

(Fourth embodiment)
The control device 10 according to the fourth embodiment of the present invention shown in FIG. 11 is different from the control device 10 shown in FIG. 1 in that the extraction interval calculation device 12 and the target rolling time calculation device 13 are not provided. Other configurations are the same as those of the first embodiment shown in FIG. The target rolling time t _Tar may be calculated by an external function such as mill pacing. The control apparatus 10 shown in FIG. 11 controls the hot rolling line 20 using the target rolling time t _Tar calculated by the external apparatus 30 having the mill pacing function on the heating furnace 21 side.

The rolling time adjusting device 17 compares the target rolling time t _Tar input from the external device 30 with the rolling required time _trm calculated by the rolling time prediction calculating device 16 so that the required rolling time _trm is the target rolling. The speed change rate α _V of the rolling speed is calculated so as to be within the time t _Tar . Based on the speed change rate α _V , a speed pattern and the like are corrected by the schedule correction device 15. When the energy consumption can be reduced, the energy consumption adjusting device 18 calculates the speed change rate α _V so as to minimize the energy consumption of the hot rolling line 20.

According to the control apparatus 10 shown in FIG. 11, under conditions rolling required time t _rm is within the target rolling time t _Tar inputted from the mill pacing function, the energy consumption can be minimized. Others are substantially the same as those in the first embodiment, and redundant description is omitted.

  As described above, the present invention has been described according to the first to fourth embodiments. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art. That is, the present invention naturally includes various embodiments that are not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 10 ... Control apparatus 11 ... Operation condition processing apparatus 12 ... Extraction interval calculation apparatus 13 ... Target rolling time calculation apparatus 14 ... Initial schedule calculation apparatus 15 ... Schedule correction apparatus 16 ... Rolling time prediction calculation apparatus 17 ... Rolling time adjustment apparatus 18 ... Energy Consumption adjusting device 20 ... Hot rolling line 21 ... Heating furnace 23 ... Coarse mill 26 ... Finishing mill 28 ... Winding machine 30 ... External device 100 ... Rolled material 260 ... Rolling stand 265 ... ISC
291 ... Coarse mill exit side thermometer 292 ... Finishing mill entry side thermometer 293 ... Finishing mill exit side thermometer

Claims (4)

A control device for a hot rolling line comprising a heating furnace and a finishing mill having a plurality of rolling stands arranged continuously and a cooling spray arranged between the plurality of rolling stands,
Target values of finishing mill exit temperature, product thickness / sheet width, plate thickness / plate width / length of slab drawn into the heating furnace, and heating for a plurality of materials to be rolled Based on the operation conditions including the number of the material to be rolled and the total processing time obtained from the operation information including the extraction temperature of the furnace, the extraction interval time during which the plurality of materials to be rolled are extracted from the heating furnace , An extraction interval calculation device that calculates the rolled material to be rolled and the subsequent rolled material so as not to collide on the hot rolling line;
Using the extraction interval time and the rolling speed included in the operation information , a target rolling time calculation device that calculates a target rolling time of a target rolled material that is one of the plurality of rolled materials,
Based on the operating conditions , as the initial value of the control reference value necessary to achieve the target plate thickness and rolled material temperature on the finish mill exit side , the flow rate of the cooling spray, and the target rolled material are the An initial schedule calculation device for calculating a speed pattern of a rolling speed conveyed on the hot rolling line;
The flow rate of the cooling spray is corrected so as to achieve the temperature of the material to be rolled , and the finishing mill outlet temperature cannot be set to the target value over the entire length of the target material to be rolled only by correcting the flow rate of the cooling spray. A schedule correction device that corrects the speed pattern using the speed change rate when the speed pattern is corrected , or when a speed change rate related to the speed pattern is input,
A rolling time prediction calculation device that calculates a rolling time required for the target rolled material using the speed pattern corrected by the schedule correction device ;
The rolling time adjustment device that calculates the speed change rate so that the rolling required time is within the target rolling time, and outputs the calculated speed change rate to the schedule correction device;
The speed of the rolling roll and the torque applied to the rolling roll at a plurality of target points that are set in the hot rolling line and that are a plurality of arbitrary calculation points in the longitudinal direction of the target rolled material and that perform temperature drop calculation. The rolling power required for rolling the target material to be rolled is proportional to the product and calculated using the speed pattern corrected by the schedule correction device, and the energy consumption obtained by time integration of the rolling power is An energy consumption adjustment device that newly calculates the speed change rate so as to be minimized, and outputs the calculated speed change rate to the schedule correction device,
Calculation of the speed change rate by the rolling time adjusting device and calculation of the speed change rate by the energy consumption adjusting device so that the rolling required time is within the target rolling time and the energy consumption is minimized. And the correction of the speed pattern by the schedule correction device is repeated to determine the flow rate of the cooling spray and the speed pattern. A first extraction interval time from when the first rolled material is extracted from the heating furnace until the second rolled material is extracted after the first rolled material by the extraction interval calculating device. And a second extraction interval time from when the second material to be rolled is extracted from the heating furnace to when the third material to be rolled is extracted next to the second material to be rolled. ,
The energy consumption adjusting device is
A first extraction interval time combination comprising the first extraction interval time and the second extraction interval time;
A second extraction interval time combination in which the first extraction interval time is increased by a certain time and the second extraction interval time is decreased by the certain time; and
Wherein the first sampling interval time decreases the predetermined time, and for the second sampling interval time each third extraction interval combinations increased the predetermined time, the first to the third sampling interval The first energy consumption consumed in the rolling process of the first rolled material calculated using the speed pattern corrected by the schedule correcting device with respect to the time and the rolling process of the second rolled material Calculate the sum of energy consumption with the second energy consumption consumed,
The flow rate of the cooling spray and the speed pattern are determined using any one of the first to third extraction interval time combinations that minimizes the sum of the energy consumption amounts. Control device for hot rolling line.   The extraction interval calculation device includes a difference between a reduction amount of the target rolled material and an average reduction amount of the plurality of rolled materials, a rolled material length of the target rolled material, and an average rolled material of the plurality of rolled materials. Calculating the extraction interval time by using the difference between the length and the difference between the target finishing mill outlet temperature of the target rolled material and the average target finishing mill outlet temperature of the plurality of rolled materials. The hot rolling line control device according to claim 1 or 2, characterized in that The hot rolling line control device according to claim 1, wherein the rolling time adjusting device uses a rolling time calculated by a mill pacing function as the target rolling time.

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