JPH08283860A - Method for creating schedule for sorting slab to heating furnace and device therefor - Google Patents

Abstract

PURPOSE: To create an effective and optimum schedule for sorting fuel charged into a heating furnace in a short time. CONSTITUTION: Neck slab and dead burning slab are detected by calculating neck degree and dead burning degree of respective slabs charged into the heating furnace, the neck slab and the dead burning slab which are detected are exchanged with each other under a prescribed condition to renew the schedule, then simulation is performed based on a renewed schedule and these processes are repeated to create an optimum schedule. Thus, the neck slab and the dead burning slab causing loss of fuel charged into the heating furnace are reduced and the optimum schedule in which difference between a target temperature and an actual extracting temperature of respective slabs is small is certainly created and number of schedule patterns to be created before obtaining the optimum schedule can be drastically reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slab heating furnace distribution schedule creating method and apparatus, and more particularly to a method and apparatus for controlling a charging furnace and a charging sequence of rolling slabs in a rolling mill having a heating furnace. Is suitable.

[0002]

2. Description of the Related Art Generally, when determining a treatment sequence and a treatment time in a hot rolling process of a slab carried from an upper process (a continuous casting process or a slab yard placed thereafter), a slab steel type, There are many rolling restrictions and heating restrictions regarding attributes such as width, thickness, and temperature, and they are arranged as many operation restrictions.

Attempts have been made using AI technology to determine the rolling sequence and charging furnace to comply with these regulations, but at present it is still insufficient. In particular, the slab charging heating furnace, that is, the slab heating furnace distribution schedule is mostly determined based on the experience of the operator.

[0004]

However, the method based on the experience of such operators does not always provide the optimum schedule, and depending on the created schedule, more fuel than necessary may be supplied to the heating furnace. It had to be thrown in, resulting in waste.

Also, Japanese Patent Application No. 6-7843 filed previously.
No. 3 proposes a method of creating a distribution schedule using a simulator. However, this method has adopted a method of searching for an optimum schedule by performing a simulation while creating all possible schedule patterns.

Therefore, when creating a distribution schedule for a large number of slabs, the number of combinations of schedule patterns becomes very large. Therefore, it takes a very long time to create all the schedule patterns and obtain the optimum distribution schedule. There was a problem that it took time.

The present invention has been made in order to solve such a problem, and it is possible to create an optimum heating furnace distribution schedule in a short time with less waste of fuel input to the heating furnace. The purpose is to do.

[0008]

The slab heating furnace distribution schedule creation method of the present invention is a heating furnace distribution schedule creation method for determining a slab charging furnace and a charging order in a rolling mill having a heating furnace. A first step of detecting a neck slab and a waste-burning slab from a plurality of slabs charged into the heating furnace;
In the second step of updating the schedule by mutually exchanging the neck slab and the waste-burning slab detected in step 1) under predetermined conditions, and burning based on the schedule updated in the second step. The method further includes a third step of performing a control simulation, and a fourth step of determining whether or not the updated schedule is optimized according to the result of the simulation in the third step. It is characterized in that an optimal heating furnace distribution schedule is created by repeatedly performing the processing from the above step to the fourth step.

Another feature of the present invention is that the predetermined condition for exchanging the neck slab and the waste slab in the second step is: target temperature of waste slab ≈ low extraction temperature of neck slab ,
Moreover, the extraction temperature of the waste-burning slab ≒ the target temperature of the neck slab.

Another feature of the present invention is that the determination of whether or not the updated schedule in the fourth step is optimized is performed based on the updated schedule in the third step. The feature is that it is performed by checking whether the total fuel input to the heating furnace obtained as a result of the simulation is smaller than the total fuel input based on the schedule before update.

Another feature of the present invention is that there are a plurality of heating furnaces, and in the first step, one specific furnace is selected from the plurality of heating furnaces and the specific furnace is selected. While detecting the neck slab from among the plurality of slabs that are charged, it is configured to detect the waste-burning slabs among the plurality of slabs that are charged into the furnace other than the specific furnace, and the selection of the specific furnace is performed. It is characterized in that an optimum heating furnace distribution schedule is created by repeatedly performing the processing from the first step to the fourth step while changing the above.

Another feature of the present invention is that there are a plurality of heating furnaces, and in the first step, one specific furnace is selected from the plurality of heating furnaces and the specific furnace is selected. While detecting the waste-burning slab from among the plurality of slabs that are charged, the neck slab is detected from among the plurality of slabs that are charged into the furnace other than the specific furnace, and the selection of the specific furnace is performed. It is characterized in that an optimum heating furnace distribution schedule is created by repeatedly performing the processing from the first step to the fourth step while changing the above.

The slab heating furnace distribution schedule preparation apparatus of the present invention is a heating furnace distribution schedule preparation apparatus for determining a slab charging furnace and a charging order in a rolling mill having a heating furnace. Neck slab detection means for detecting a neck slab from a plurality of slabs to be inserted, waste slab detection means to detect a waste slab from a plurality of slabs charged into the heating furnace, and the neck slab A slab exchanging means for updating the schedule by exchanging the neck slab detected by the detecting means and the waste-burning slab detected by the waste-burning slab detecting means with each other under predetermined conditions, and the slab exchanging means. Simulation means for simulating combustion control based on the updated schedule, and the above-mentioned simulator. Depending on the simulation result by preparative means, the update schedule is characterized by comprising determination means for determining whether or optimized.

[0014]

Since the present invention comprises the above-mentioned technical means, the neck slab and the waste-burning slab, which cause the waste of the input fuel due to their existence, are mutually separated under predetermined conditions. By replacing, the number of neck slabs and waste-burning slabs should be reduced so that the target temperature of each slab charged into the heating furnace does not differ significantly from the target temperature of the slabs before and after it. This makes it possible to reduce the difference between the target temperature of each slab and the actual extraction temperature, and reliably reduce the waste of input fuel.

Further, according to the present invention, the schedule patterns are sequentially created only by exchanging the neck slab and the waste-burning slab, and an optimal heating furnace distribution schedule with less waste of input fuel is created.
Compared to the conventional method in which schedule patterns are created while exchanging all slabs, it is possible to significantly reduce the number of schedule patterns created until the optimum schedule is obtained.

According to the second aspect of the present invention, the neck slab is replaced with a slab having a target temperature which is substantially the same as the target temperature of the slabs before and after the neck slab, and at the same time, the waste-burning slab is extracted. Since the slab having a temperature substantially the same as the target temperature is replaced, the neck slab and the waste-burning slab can be reduced at the same time.

Further, according to the third aspect of the present invention, it is judged whether or not the schedule is optimized by using the total fuel input to the heating furnace as an evaluation amount, and therefore, the heating that minimizes the total fuel input is performed. It is possible to create a furnace distribution schedule with certainty.

Further, according to the invention described in claim 4 or 5, when there are a plurality of heating furnaces, it becomes possible to optimize all the schedules for each heating furnace at the same time.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a flow chart showing a processing flow of a method for creating a heating furnace distribution schedule for slabs according to the present embodiment, and FIG. 2 is a view showing a configuration of a hot rolling factory.

In FIG. 2, the slab placed in the slab storage area 201 or the slab carried by the freight car 202 is
It is placed on the table 203 in front of the heating furnace and loaded into the heating furnace 204 composed of three furnaces 204a, 204b, and 204c of No. 1 to No. 3 furnaces. The slab charged into this heating furnace 204 is the actual temperature before charging (charge slab temperature)
The target temperature for heating and heating varies, and an appropriate furnace is determined and charged by the scheduling method described below.

The slab charged in the heating furnace 204 is heated by the temperature of the charging slab to give the in-furnace time (time spent in the heating furnace 204) and the extraction temperature. The slab that has reached the extraction temperature according to the schedule waits for the time interval required for rolling with the previous extraction slab before the heating furnace 2
It is extracted from 04. And VSB (slab width control rolling mill) 205, rough rolling mill 206 and finish rolling mill 20
After being rolled in No. 7, it is water-cooled by ROT (cooling table) 208 and wound by a coiler 209. The coil thus manufactured is transported to the product storage 210.

Next, the above-described scheduling method for determining the charging furnace will be described with reference to the flowchart of FIG. In this scheduling method, the charging heating furnace and the charging sequence are determined for about 100 slabs by the processing shown in the following steps S1 to S7.

First, in step S1, a combustion control simulation of all heating furnaces is performed based on the initial setting of heating furnace distribution, and the extraction temperature TH (i) (i is the slab extraction sequence number) for each furnace. ), Low extraction temperature TL (i), total input fuel, total extraction temperature deviation and total deviation. As a result, a graph as shown in FIG. 3 is obtained for each furnace. The initial setting can be arbitrarily performed.

Here, the extraction temperature TH (i) is determined by the heating furnace 20.
4 is the predicted temperature when each slab is actually heated and extracted. In addition, the low extraction temperature TL (i) is the target temperature T of the n slabs before and after the
It is the temperature obtained by the weighted average of M, and is represented by the envelope connecting the low target temperature TM (i) of each slab in the graph of FIG.

[0025]

[Equation 1]

As is clear from FIG. 3, these extraction temperature TH (i), target temperature TM (i) and low extraction temperature TL (i).
As shown in the following (Equation 2), the relationship with and is always higher in the order of the extraction temperature TH (i), the target temperature TM (i), and the low extraction temperature TL (i). TH (i) ≧ TM (i) ≧ TL (i) (Equation 2)

Further, the total fuel input is for each furnace 2 when the extraction temperature TH (i) as described above is set for each slab.
It is the total fuel injected into 04a, 204b and 204c. The total extraction temperature deviation is the sum of the differences between the extraction temperature TH (i) and the target temperature TM (i) for each slab. The total deviation of heat is the sum of the temperature differences in the inner surface caused by the temperature distribution in the thickness direction of the slab, and is calculated by a predetermined heat transfer calculation.

Next, in step S2, one of the furnaces 204a, 204b, 204c constituting the heating furnace 204 is selected as a specific furnace. In the next step S3, the neck degree of each slab charged in the specific furnace selected in step S2 and the waste firing degree of each slab charged in a furnace other than the specific furnace are calculated.

The neck degree means a target temperature TM (i) of a certain slab and a low extraction temperature T as shown in the following (formula 3).
It shows the temperature difference from L (i). Neck degree (i) = TM (i) -TL (i) (Equation 3) A slab in which the target temperature TM of a certain slab is significantly higher than the target temperature TM of the slabs before and after that, that is, the neck degree is Large slabs are referred to below as "neck slabs"
Call. In the example of FIG. 3, it can be seen that there are three such neck slabs.

If there is this neck slab, the extraction temperature TH of the slabs before and after the neck slab becomes much higher than the target temperature TM, and it becomes impossible to set an appropriate extraction temperature TH. Therefore, if the neck slab is loaded in the same furnace or in another furnace in an appropriate order to perform scheduling so as to eliminate the neck slab, an appropriate extraction temperature TH can be set.

Further, the waste baking degree means the extraction temperature TH (i) of a certain slab and the target temperature TM, as shown in the following (Equation 4).
It shows the temperature difference from (i). Waste firing degree (i) = TH (i) -TM (i) (Equation 4) The extraction temperature TH of a slab is the target temperature TM of the slab.
A slab that is considerably higher than that of slab, that is, a slab with a high degree of waste firing is referred to as "waste firing slab" below.
In the example of FIG. 3, it can be seen that several such waste-burning slabs exist next to the above-mentioned three neck slabs.

This waste-fired slab is a slab that causes the waste fuel to be wasted by heating the slab more than necessary because its extraction temperature TH is much higher than the target temperature TM. Therefore, if the scheduling is performed so as to eliminate this waste-burning slab, the total fuel input can be reduced.

Next, in step S4, the neck slab in the specific furnace and the waste-fired slab in another furnace are exchanged. In the process of step S4, first, the neck degrees calculated in step S3 are rearranged in descending order,
Create a neck slab list. In addition, the above step S
A waste burning slab list is created by rearranging the waste burning degrees calculated in 3 in descending order.

Then, the slab at the top of each list is given priority, and a pair of a neck slab n and a waste-burning slab m which best meet the following conditions 1) and 2) is found, and the slabs are mounted between the pairs. By replacing the furnace,
Update the contents of the schedule. Condition 1) Target temperature TM (m) ≈ low extraction temperature TL (n) Condition 2) Extraction temperature TH (m) ≈ target temperature TM (n)

For example, when the No. 1 furnace 204a shown in FIG. 2 is selected as the specific furnace, the No. 1 furnace 204a is selected.
When the above-mentioned neck slab and the waste firing slab in the other furnace No. 2 furnace 204b or No. 3 furnace 204c satisfy the above conditions, the neck slab and the waste firing slab are exchanged and charged. Change the furnace. At this time, if there are a plurality of combinations of the neck slab and the waste-burning slab that satisfy the above conditions, all of them are exchanged.

In this way, by mutually exchanging a pair of slabs satisfying the conditions 1) and 2) at the same time, the neck slab in the specific furnace can be made to have substantially the same temperature as the target temperature of the slabs before and after the neck slab. This means that the slab having the same temperature as the target temperature is replaced, and at the same time, the waste-burning slab in the other furnace is replaced with the slab having the target temperature which is substantially the same as the extraction temperature.

Therefore, according to this embodiment, it is possible to reduce the number of neck slabs and waste firing slabs at the same time. As a result, the extraction temperature TH of the slabs before and after the neck slab cannot be set to an appropriate temperature due to the presence of the neck slab, and the input fuel is wasted. The slab can be heated more than necessary, and the inconvenience of wasting the input fuel can be eliminated at the same time by compensating each other.

Of course, the slab satisfying one of the above conditions 1) and 2) may be found and the charging furnace may be replaced. However, in this case, it is only possible to optimize the schedule for one reactor. Therefore, it is preferable to exchange the charging furnace between slabs that satisfy both the above conditions 1) and 2) at the same time.

Next, in step S5, a combustion control simulation similar to that performed in step S1 is performed according to the new schedule created by replacing the charging furnace as described above, and extraction is performed for each furnace. The temperature TH (i), the low extraction temperature TL (i), the total input fuel, the total extraction temperature deviation and the total deviation of heat are obtained again.

Then, in step S6, it is determined whether or not the heating furnace distribution schedule for each slab is optimized. That is, in the process of step S6, the total input fuel before updating the schedule and the total input fuel after updating the schedule are compared. Then, if the total input fuel after the update is smaller, it is possible that the total input fuel can be further reduced by exchanging the neck slab and the waste-burning slab, and the process returns to step S2.

In step S2, a furnace different from the initially selected specific furnace is newly selected as the specific furnace. Hereinafter, the same processing as above is performed in steps S3 to S6. On the other hand, if the total fuel input before update is smaller, step S
The process proceeds from step 6 to step S7, and the heating furnace distribution is completed using the schedule before the update as the optimum schedule.

By repeating the above steps S2 to S6, the number of neck slabs and waste-burning slabs can be significantly reduced for each slab charged into the heating furnace 204, and each slab can be reduced. Extraction temperature TH
The difference between (i) and the target temperature TM (i) can be reduced. This makes it possible to create an optimal distribution schedule that minimizes the waste of fuel input to the heating furnace 204. FIG. 4 shows an example in which a distribution schedule is actually created by the above method.

In FIG. 4, Step 1 shows the result when the simulation is performed based on the initial setting (for example, setting by the mounting industry), and Steps 2 to 5 are No. 1 furnace 204a and No. 2 furnace 204b, 3 respectively. Furnace 204
The results obtained when the simulation is performed by sequentially selecting the c and No. 1 furnace 204a as the specific furnace are shown. As can be seen from FIG. 4, according to the present embodiment, it is possible to reduce the total input fuel and the total extraction temperature deviation while keeping the total extraction temperature biased heat at the same level.

Next, FIG. 5 shows the configuration of an apparatus for carrying out the heating furnace distribution schedule preparation method as described above. As shown in FIG. 5, the slab heating furnace distribution schedule creating apparatus according to the present embodiment includes a specific furnace selecting unit 1
A neck degree calculating section 2, a waste burning degree calculating section 3, a sorting section 4, a slab exchanging section 5, a schedule storing section 6,
A simulator 7, a simulation result storage unit 8,
It is composed of a determination unit 9 and an output unit 10. The neck degree calculating unit 2, the waste burning degree calculating unit 3, and the sorting unit 4 constitute a neck slab detecting unit and a waste burning slab detecting unit.

The specific furnace selection unit 1 performs the specific furnace selection process in step S2 shown in FIG. The specific furnace selection unit 1 may have an input device such as a keyboard and a mouse, and may be configured to manually select the specific furnace, or No. 1 furnace → No. 2 furnace → No. 3 furnace → No. 1 A specific furnace may be automatically selected such as furnace →.

Neck degree calculating section 2 and waste burning degree calculating section 3
Performs the neck degree calculation processing and the waste burning degree calculation processing in step S3 of FIG. 1, respectively. That is, the neck degree calculation unit 2 calculates the neck degree of each slab loaded into the specific furnace selected by the specific furnace selection unit 1.
The waste burnt degree calculation unit 3 also calculates the waste burned degree of each slab charged in a furnace other than the specific furnace selected by the specific furnace selecting unit 1.

The sorting section 4 and the slab exchanging section 5 are shown in FIG.
In step S4, the neck slab and the waste-burning slab are replaced. That is, the sorting unit 4 creates the neck slab list based on the neck degree calculated by the neck degree calculating unit 2 and also the waste firing slab based on the waste firing degree calculated by the waste firing degree calculating unit 3. Create a list. Then, the slab exchanging unit 5 mutually exchanges a pair of slabs that simultaneously satisfy the conditions 1) and 2) in the order of the neck degree and the waste firing degree in the neck slab list and the waste firing slab list, Update the contents of the schedule.

The schedule information updated by the slab exchange section 5 performing the slab exchange is as follows:
It is stored in the schedule storage unit 6. In the initial stage, the schedule storage unit 6 stores the step S of FIG.
The information of the schedule based on the initial setting set in 1 is stored. The updated schedule is also given to the simulator 7.

The simulator 7 carries out a simulation of combustion control based on the schedule given by the simulator 7, and extracts the extraction temperature TH (i), the low extraction temperature TL (i), the total input fuel and the total extraction temperature for each furnace. Calculate deviation and total deviation. Each information obtained as a result of this simulation is stored in the simulation result storage unit 8.
The total input fuel stored in the simulation result storage unit 8 is read out in the next Step and given to the determination unit 9.

The determination unit 9 compares the total fuel input after the schedule update obtained by the simulator 7 with the total fuel input before the schedule update stored in the simulation result storage unit 8 to calculate the schedule. It is determined whether the optimization of is completed.

When the optimization is completed, the output unit 10
Reads the information of the schedule (pre-update schedule) in the previous Step from the schedule storage unit 6 and outputs it as the optimum schedule. Further, when the optimization is not completed, a new specific furnace is selected in the specific furnace selection unit 1 and stored in the simulation result storage unit 8 in the neck degree calculation unit 2 and the waste firing degree calculation unit 3. The neck degree and the waste burning degree are calculated again using the extraction temperature TH (i) and the low extraction temperature TL (i).

As described above, in this embodiment, one specific furnace is selected from the three heating furnaces, and the neck slab and the waste burned slab that cause the waste of the input fuel are described above. Detected in the specified furnace and other furnaces respectively.
Next, the neck slab in the specific furnace and the waste-burning slab in another furnace are exchanged under the conditions 1) and 2) to update the schedule, and the combustion control simulation is performed based on the updated schedule. Then, the above processing is repeated until the total fuel input obtained as a result does not become smaller, thereby creating a heating furnace distribution schedule for slabs.

By mutually exchanging the neck slab and the waste-burning slab satisfying the predetermined conditions in this manner, the number of neck slabs and waste-burning slabs in each heating furnace can be simultaneously reduced. Therefore, it is possible to prevent the target temperature TM of each slab charged in each heating furnace from being significantly different from the target temperature TM of the slabs before and after that, and the target temperature TM of each slab and the actual extraction. The difference from the temperature TH can be reduced. As a result, it is possible to surely obtain an optimal distribution schedule that minimizes the waste of the fuel input to each heating furnace regardless of the experience of the operator or the skill level.

Moreover, when creating such an optimum distribution schedule, the neck slab and the waste-burning slab that cause the waste of the input fuel are detected,
Since the distribution schedule is created only by exchanging these with each other, the number of schedule patterns to be created can be significantly reduced compared to the conventional method in which schedule patterns are created while exchanging all slabs. Therefore, the calculation time required to obtain the optimum distribution schedule can be significantly shortened.

In the above embodiments, the example in which the neck slab in the specific furnace and the waste-burning slab in the other furnace are exchanged has been described, but conversely, the waste-burning slab in the specific furnace and the waste-burning slab in the other furnace are replaced. The neck slab may be replaced. Further, although the neck slab and the waste-burning slab are exchanged between different heating furnaces, they may be exchanged in the same furnace. Even if the heating furnaces are exchanged between different heating furnaces, the same result as in the same furnace may be obtained by repeating the process.

Further, in the above embodiment, it is judged whether or not the optimization is completed by comparing the total input fuels. However, the total extraction temperature deviation, the total deviation, or a combination thereof is also judged as the evaluation amount. It may be done. In addition, in the above-described embodiment, the low extraction temperature TL (i) is set to (Equation 1)
However, the present invention is not limited to this calculation method. For example, it is possible to change the weighting method and take a weighted average. Also,
In the above embodiment, the number of heating furnaces is three, but this may be any number.

[0057]

As described above, the present invention detects a neck slab and a waste-burning slab from among a plurality of slabs charged into a heating furnace, and determines the detected neck slab and the waste-burning slab as predetermined. The heating furnace distribution schedule was created by repeating the process of exchanging each other under the conditions and updating the schedule, and performing the simulation based on the updated schedule. Despite this, it is possible to reduce the number of neck slabs and waste-burning slabs that cause waste in the fuel input to the heating furnace, and reduce the difference between the target temperature of each slab and the actual extraction temperature. It is possible to reliably create an optimal heating furnace distribution schedule with little waste of input fuel. Moreover, according to the present invention,
Compared with the conventional method that creates a schedule pattern while exchanging all slabs, the number of schedule patterns to be created can be significantly reduced, so the calculation time to obtain the optimal schedule should be significantly shortened. You can

According to the second aspect of the present invention, the predetermined conditions for exchanging the neck slab and the waste slab are: target temperature of waste slab ≈ low extraction temperature of neck slab,
Moreover, since the extraction temperature of the waste-burning slab ≒ the target temperature of the neck slab, the neck slab and the waste-burning slab can be reduced at the same time, and a more optimal heating furnace distribution schedule can be created in a shorter time. .

According to the third aspect of the present invention, the determination whether or not the updated schedule is optimized is performed by updating the total input fuel obtained as a result of the simulation performed based on the updated schedule. Since it is performed by checking whether the total input fuel is smaller than the total input fuel based on the previous schedule, it is possible to reliably create the heating furnace distribution schedule that minimizes the total input fuel.

Further, according to the invention of claim 4 or 5, the neck slab and the waste-burning slab are detected from the plurality of heating furnaces and they are exchanged with each other. All the distribution schedules for the furnaces can be optimized at the same time, and the heating furnace distribution schedule that minimizes the total fuel input to each heating furnace can be reliably created.

[Brief description of drawings]

FIG. 1 is a flowchart showing a processing flow of a method for creating a heating furnace distribution schedule for slabs according to this embodiment.

FIG. 2 is a diagram showing a configuration of a hot rolling factory.

FIG. 3 is an extraction temperature TH (i) and a low extraction temperature TL (i) for each slab obtained by performing a combustion control simulation, and a target temperature TM for each slab.
It is a graph which shows the relationship with (i).

FIG. 4 is a diagram showing an example in which a schedule is actually created by the slab heating furnace distribution schedule creation method according to the present embodiment.

FIG. 5 is a block diagram showing the configuration of a heating furnace distribution schedule preparation device for slabs according to the present embodiment.

[Explanation of symbols]

 1 Specific Furnace Selection Section 2 Neck Degree Calculation Section 3 Waste Burning Rate Calculation Section 4 Sorting Section 5 Slab Replacement Section 6 Schedule Storage Section 7 Simulator 8 Simulation Result Storage Section 9 Judgment Section 10 Output Section 204 Heating Furnace

Claims (6)

[Claims] 1. A heating furnace distribution schedule preparation method for determining a charging furnace and a charging order of slabs in a rolling mill having a heating furnace, wherein a neck slab is selected from a plurality of slabs charged into the heating furnace. And a waste-burning slab are detected in the first step, and a schedule is updated by mutually exchanging the neck slab and the waste-burning slab detected in the first step under predetermined conditions. The updated schedule is optimized according to a step, a third step of performing a simulation of combustion control based on the schedule updated in the second step, and a result of the simulation in the third step. And a fourth step of determining whether or not the process is repeated, and the processing from the first step to the fourth step is repeated. Furnace allocation scheduling method slabs, characterized in that so as to create an optimal furnace distribution schedule by performing. 2. The predetermined condition for exchanging the neck slab and the waste slab in the second step is that the target temperature of the waste slab is approximately equal to the low extraction temperature of the neck slab,
The method for creating a heating furnace distribution schedule for slabs according to claim 1, wherein the extraction temperature of the waste-burning slab ≈ the target temperature of the neck slab. 3. The determination as to whether or not the updated schedule in the fourth step is optimized is performed by the heating furnace obtained as a result of a simulation performed based on the updated schedule in the third step. 3. The method for creating a heating furnace distribution schedule for slabs according to claim 1, wherein the method is performed by checking whether or not the total input fuel of is less than the total input fuel based on the schedule before update. 4. A plurality of heating furnaces are present, and in the first step, one specific furnace is selected from the plurality of heating furnaces, and a plurality of slabs are charged into the specific furnace. From the first step while changing the selection of the specific furnace while detecting the waste slab from the plurality of slabs charged into the furnace other than the specific furnace, while detecting the neck slab from the above. An optimal heating furnace distribution schedule is created by repeatedly performing the processing up to the fourth step. The method for creating a heating furnace distribution schedule for slabs according to claim 1, wherein the heating furnace distribution schedule is created. . 5. A plurality of heating furnaces are present, and in the first step, one specific furnace is selected from the plurality of heating furnaces, and a plurality of slabs are charged into the specific furnace. The waste slab is detected from the above, and the neck slab is detected from a plurality of slabs charged into a furnace other than the specific furnace. While changing the selection of the specific furnace, the first step to the above An optimal heating furnace distribution schedule is created by repeatedly performing the processing up to the fourth step. The method for creating a heating furnace distribution schedule for slabs according to claim 1, wherein the heating furnace distribution schedule is created. . 6. A heating furnace distribution schedule preparation device for determining a charging furnace and a charging order of slabs in a rolling mill having a heating furnace, wherein a neck slab is selected from a plurality of slabs charged into the heating furnace. And a waste slab detecting means for detecting a waste firing slab from a plurality of slabs charged in the heating furnace, a neck slab detected by the neck slab detection means and the waste Slab replacement means for updating the schedule by mutually exchanging the waste-burned slab detected by the baked slab detection means under predetermined conditions, and a simulation of combustion control based on the schedule updated by the slab replacement means. According to the result of the simulation by the simulation means and the above-mentioned simulation means, New schedule heating furnace distributing scheduling apparatus slabs, characterized by comprising determination means for determining whether or optimized.