JPH0813038A - Method for deciding extracting time from heating furnace - Google Patents

Abstract

PURPOSE:To provide a deciding method for extracting time from a heating furnace, by which the loss of rolling chance is avoided and the smooth operation can be carried out even if the carrying schedule of materials changes by an unexpected trouble of the equipment or the manual intervention of an operator, when plural pieces of the steel materials extracted with the specific extracting pitch is in a rolling line. CONSTITUTION:The time which each material extracted from the heating furnace reaches one or more of detecting positions for detecting the material carrying time in the rolling line, is predicted and also, actually measured (S1). The max. value of the time obtained by deducting the correcting time based on a delay time of the actual measured value to the predicted value at each detecting position of the material reached to each detecting position in the past time from a delay time of the actual measured value to the predicted value at each detecting position of the material reaching each detecting position, is added to the extracting scheduled time of the material extracted in the following time (S2, S3). By the above constitution, the smooth operation, etc., can be realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating furnace extraction time determination method, and more particularly to a heating furnace extraction time determination method for determining the extraction time of the material extracted from the furnace into the rolling line in the heating furnace material. It is a thing.

[0002]

2. Description of the Related Art Generally, in a continuous hot rolling process, as shown in FIG. 2, one or a plurality of heating furnaces 1 are provided on a roller table called a rolling line. This heating furnace 1
A steel material called a slab is extracted from the slab and is roughly rolled by a plurality of rough rolling machines 2 to form a rectangular thick steel plate called a rough bar. This rough bar is further equipped with finishing mills 3
To continuously finish rolling to the required thickness. The steel sheet after finish rolling is wound by the coiler 4 to produce a hot rolled wide strip steel. Conventionally, an operator has determined the appropriate extraction pitch while monitoring the position of the steel material on the rolling line and manually extracted, or automatically extracted by the method described below. FIG. 4 shows an example of such a conventional automatic extraction method introduced in Japanese Patent Laid-Open No. 62-30812. That is, in FIG. 4, the rolling schedule of the next extracted material is first calculated, and the time from the start of extraction to the arrival of each facility, the time of rolling start and the end of rolling at the rough rolling mill 2 or finish rolling mill 3, and the like The extraction time of the next extraction material can be predicted so that the required interval time of the equipment that will become the bottleneck of the next extraction material can be obtained based on the predicted transportation schedule of the material extracted immediately before and the actual extraction time of the material. Had been decided. At this time, if the material transfer schedule changes due to a sudden equipment failure or manual operator intervention, problems such as material collision, loss of rolling opportunities, or lowering of the rough bar temperature may occur. For this, the extraction time is corrected by using the time difference (delay) between the prediction and the actual time from the arrival of each of the preceding multiple materials and the extraction of rolling start and rolling end. That is, according to the conventional method, it is assumed that there are N locations where interference occurs on the rolling line (hereinafter referred to as "interference points"), and the Lth interference of the material predicted when the preceding material before k is extracted. The on-time and off-time of the point are set as T ^P _onLk and T ^P _offLk , respectively. On the other hand, to turn on the L-th interference point from next extraction material is extracted, the time until the off-t ^P _ONL, a t ^P _OFFL. Time t ^P _onL , t
^By _predicting the schedule of materials in advance, ^P _offL can be predicted and calculated from the specifications of materials and equipment. On the other hand, the actual values T ^A _onLk and T ^A _offLk at the time when the preceding k preceding material turned off or turned on the L-th interference point were measured (S
1 '), using this, amend as follows. That is, all L-th interference points L, k on the rolling line
Among some of the actual value in the preceding material k of the front, ΔT = T ^A -T ^P (also a negative value) is to select the time difference [Delta] T which maximizes (S2 '), the following extraction time T _ext, It is corrected as T _ext = T ⁰ _ext + ΔT (S3 ′), and the material is extracted at that time.

[0003]

The heating furnace as described above
In the extraction time determination method, especially on the rolling line,
A point that compares the predicted time with the actual time as a crossing point
There is only one steel near or at the upstream side.
By eliminating the fluctuations in the steel schedule of
If the schedule of the next extraction material is immediately normalized,
It is thought to be effective for minutes. However, usually continuous hot pressure
In the rolling process, multiple steel products are constantly rolled on the rolling line.
ing. Correct the extraction time of the next extraction material in this state.
Then, the prediction / actual error at each interference point input one after another
Therefore, the productivity may be significantly deteriorated.
Here, for convenience, the steel materials around the heating furnace 1 and the rough rolling mill 2 are
Paying attention to only the movement of the rolling mill, especially the interference point when the rough rolling mill 2 is turned on.
The explanation will be limited to only the time. As shown in FIG.
Steel materials 5a, 5b extracted and rolled from several heating furnaces 1
Are respectively rolled by the rough rolling mills 2b and 2c.
It is assumed to have been transported. Here, without adjusting the temperature of the steel
For any reason, the steel material 5a is directly inserted into the rough rolling mill 2c.
It is assumed that the transportation is stopped in the front and the vehicle is in a waiting state. Then later
The steel material 5b that was rolled in one direction also prevents collision with the steel material 5a
Therefore, the rough rolling mill 2b is in a waiting state immediately before being bitten.
And ΔT₁After 5 seconds, the steel material 5a is released from the waiting state
The sheet is rolled by the rolling mill 2c and is spread between the rough rolling mills 2b-2c.
When the base material is produced, the steel material 5b is also started to be conveyed and the rolling is started.
Be started. Here, the predicted value T at the on time of the rough rolling mill 2c
₁ ^P _Four, Actual value T₁ ^A _FourThe difference between the next extraction material 5c will be extracted
Since it is reflected in the time, ΔT₁’= T₁ ^A _Four-T₁ ^P _Four Time difference ΔT₁’(≒ ΔT₁) Will be the first extraction next
Time T⁰ _extIn addition to fix. T_{1 ext}= T₁ ⁰ _ext+ ΔT₁’

Then, the state in which the steel material 5c is extracted at the time T _{1 ext} where it is reflected is shown in FIG. 3 (b). Steel 5
Reference character b represents a state immediately after rolling in the rough rolling mill 2b and rolling in the rough rolling mill 2c. After that, the steel material 5b turns on the rough rolling mill 2c, but here again, since the difference between the initially scheduled on-time and the actual on-time is reflected in the next extracted material, ΔT ₂ '= T ₂ ^A ₄ −T ₂ ^P ₄ becomes the time difference ΔT ₂ 'seconds to fix in addition to the next extraction scheduled time ^{_{T 2 0 ext, T 2 ext}} = T 2 0 ext + ΔT 2' have made time and new extraction scheduled time of the next extraction material 5d. However, this time difference ΔT ₂ 'includes a delay time corresponding to the time difference ΔT ₁ ' which has already been reflected in the extraction material 5c, and the steel material 5a is delayed by the time difference ΔT ₁ 'second, so that the steel material 5a is delayed.
Although the extraction of c was delayed, the steel material 5d would also be delayed. The present invention has improved the method for determining the extraction time of the heating furnace in order to solve the problems in the prior art, and the steel materials extracted by a predetermined extraction pitch are on multiple rolling lines, and the equipment suddenly goes out. It is an object of the present invention to provide a heating furnace extraction time determination method capable of avoiding the loss of rolling opportunity and realizing smooth operation even if the material transfer schedule changes due to a failure or manual intervention of an operator.

[0005]

In order to achieve the above object, the present invention provides a heating furnace extraction time determination method for determining the extraction time of the material extracted from the furnace into the rolling line during the heating furnace existing furnace. , Predicting and actually measuring the time when each of the extracted materials arrives at one or more detection positions for detecting the material transportation time on the rolling line, and actually measuring the material arriving at each of the detection positions at each of the detection positions Next, the maximum value of the time obtained by subtracting the correction time based on the delay time from the predicted value of the actual measurement value of the material arriving at each of the detection positions before that is extracted from the delay time of the predicted value of the value. It is configured as a heating furnace extraction time determination method characterized in that it is added to the scheduled extraction time of the material. Further, it is a heating furnace extraction time determination method in which the above-mentioned correction time is a time obtained by accumulating past correction times.

[0006]

According to the present invention, when determining the extraction time of the material extracted from the furnace to the rolling line in the heating furnace,
First, the time at which each of the extracted materials arrives at one or more detection positions for detecting the material transportation time on the rolling line is predicted and measured. Next, from the delay time of the material arriving at each of the detection positions with respect to the predicted value of the actual measurement value at each of the detection positions, the delay with respect to the predicted value of the actual value of the material that has arrived at each of the detection positions before The maximum value of the time less the time-based modification time is added to the scheduled extraction time of the next extracted material. As a result, even if there are multiple steel materials extracted at the specified extraction pitch on the rolling line and the material transfer schedule changes due to a sudden equipment failure or manual intervention by the operator, the current extraction material will not By correcting the maximum value of the time difference between the predicted value and the actual value found in, the internal time difference between the predicted value and the actual value due to the same cause has already been reflected in the core material after the next extraction material. It is possible to avoid loss of rolling opportunity and realize smooth operation by correcting the scheduled extraction time by the time excluding the specified time. Further, along with this, it is possible to reduce the fuel consumption rate of the heating furnace by an amount corresponding to the shortening of the material time.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the accompanying drawings for the understanding of the present invention. The following embodiments are examples of embodying the present invention and are not intended to limit the technical scope of the present invention. 1 is an explanatory view showing a schematic flow of a heating furnace extraction time method according to an embodiment of the present invention, FIG. 2 is a schematic view showing a schematic configuration of a hot rolling line (shared with a conventional example), and FIG. [Fig. 6] is an explanatory view showing a threaded state of a hot rolling line (shared with a conventional example). As shown in FIG. 1, the heating furnace extraction time determination method according to the present embodiment, when determining the extraction time of the material to be extracted from the furnace to the rolling line in the heating furnace, convey the material on the rolling line. Predict the time when each of the extracted materials arrives at one or more detection positions for detecting the time, and actually measure (S1) the predicted value of the measured value at each detection position of the material that has arrived at each detection position. Extraction of the material to be extracted next is the maximum value of the time obtained by subtracting the correction time based on the delay time from the predicted value of the actual measurement value at each detection position of the material that has arrived at each detection position before that It is configured to be added to the scheduled time (S2, S3). The correction time may be a time obtained by accumulating past correction times. Hereinafter, this method will be described in detail with reference to FIGS. In the continuous hot rolling line as shown in FIG. 2, the slab (corresponding to the material) extracted from the heating furnace 1 is roughly rolled by the rough rolling mill 2 to become a rough bar, and further finish rolled by the finish rolling mill 3. After being made into a product, it is wound up by the coiler 4. Here, the detection position is set to the center of each of the rough rolling mills 2, and the control event is the start of biting of the rough bar into the rough rolling mill, that is, mill-on. Further, the case where the rough bars that can be corrected are all the rough bars that reach the above detection position, and the case where the slab is extracted from the furnace without any one rough bar on the rolling line will be described.

First, as shown in FIG. 3 (a), the steel material 5a which is the first extracted slab is rolled into a rough rolling mill 2
At the stage of reaching the upstream side of c, it is assumed that the steel material 5a is stopped due to the temperature adjustment of the steel material or the like, and enters the waiting state. Then, the steel material 5b rolled in the rear also becomes a waiting state on the upstream side of the rough rolling mill 2b in order to prevent collision with the steel material 5a. After waiting time ΔT ₁ second, steel material 5a
When the waiting state is released and rolling is started by the rough rolling mill 2c, a space is created between the rough rolling mills 2b-2c, so that the steel material 5b is also restarted to be rolled. Here, the predicted value of the on time of the rough rolling mill 2c from the start of extraction for the steel material 5a is T ₁ ^A ₄ , and the actual value is T ₁ ^P ₄
Then, the difference is obtained by the extraction pitch control computer 6 and reflected in the extraction scheduled time of the next extraction material 5c. That is corrected in addition to [Delta] T ₁ beginning of the next extracted scheduled time T ₁ ⁰ _ext of ^{_{'= T 1 A 4 -T 1}} P 4 becomes modification time [Delta] T _1' s steel plates 5c. Here, the reason why the correction time is ΔT ₁ ′ second is that there is a slight deviation from the waiting time ΔT ₁ second due to delay or slip. T _{1 ext} = T ₁ ⁰ _ext + ΔT ₁ 'The time T _{1 ext is} set as the extraction scheduled time. On the other hand, T
_{When the} steel material 5b is also turned on to the rough rolling mill 2b by the time of _{1 ext,} the predicted value of the on time of the rough rolling machine 2b from the extraction time of the steel material 5b is T ₂ ^P ₃ , and the measured value is T
_{If it is 2} ^A ₃ , the difference is calculated and the scheduled extraction time of the next extraction material 5c is corrected again. However, for the second and subsequent corrections to the next extraction material, the corrections are made only when the correction value is longer than the correction value determined before that. That is, steel material 5b
In the case of, the latest extraction represented by the difference between the post-correction extraction time at which the modification time ΔT ₁ ″ = T ₂ ^A ₃ −T ₂ ^P ₃ and the originally scheduled extraction time is ΔT ₁ ″. When it is larger than the time correction amount (T _{1 ext} −T ₁ ⁰ _ext ), the newly generated ΔT ₁ ″ is used as the extraction time correction amount and the extraction time is corrected. T _{1 ext} = T ₁ ⁰ _ext + ΔT ₁ ”

As described above, it is assumed that the correction occurs every time the steel material reaches the detection position before the extraction of the next extraction material is started, and the predicted time and the actual time from the extraction of the steel material to the position are obtained. If the difference is less than the extraction time adjustment amount before the occurrence of the event, the extraction scheduled time is adjusted each time. Next, FIG. 3B shows a state immediately after the steel material 5c is extracted from the heating furnace 1 at the time T _{1 ext} where they are reflected. Steel 5a has already been transported from the rough rolling zone to the finishing rolling zone, and steel 5b
Has finished rolling in the rough rolling mill 2b and is about to finish rolling in the rough rolling mill 2c.
Is about to be rolled. Here, the final correction amount (T _{1 ext} − when the steel material 5c is extracted
It is assumed that T ₁ ⁰ _ext ) is recorded at this time for all rough bars (here, steel material 5b) upstream of the detection position. Then, after a while, the steel material 5b turns on the rough rolling mill 2c, and here again, the extraction pitch control computer 6 calculates the time difference between the on time from the initially scheduled extraction start and the actual on time. Delay of ^{_{ΔT 2 '= T 2 A 4}} -T 2 P 4 becomes the time difference [Delta] T _2' difference a is but begin steel 5b with second plan and actual is due to delay of steel 5a, the delay time otherwise As long as the steel material 5b is not delayed due to the above factor, there will be no significant difference even if there is some deviation from the delay time of the steel material 5a. Therefore, since this time difference ΔT ₂ 'includes a delay time corresponding to ΔT ₁ ' which has already been reflected in the extraction material 5c, the time already reflected in the extraction material 5c is subtracted from it, and the remaining time is subtracted from the next extraction scheduled time ΔT. ₂ ⁰
Need to fix for _ext . In other ^{_{words, ΔT 2 ext = ΔT 2 0}} ext + ΔT 2 '- have a _(T 1ext -T ₁ ⁰ _ex) becomes time T _{2 ext} to the new extraction scheduled time of the next extraction material 5d.

Hereinafter, each time the material on the rolling line reaches the detection position, the next extraction material is corrected. That is, the next extraction scheduled time is corrected by the amount of time obtained by subtracting the total value of the times when the extraction times are finally corrected for the materials extracted after the reaching material from the prediction error at the detection position of the same material. As the correction amount, the maximum value among the correction amounts thus obtained at each detection position of each material is used. As a result, the time reflected in the extracted material can be removed from the time delayed due to the same cause, so that the delay on the rolling line is automatically taken in without extracting the rolling efficiency, and the extraction pitch Can be modified. As a result, even if there are several materials extracted at the specified extraction pitch on the rolling line and the material transfer schedule changes due to a sudden equipment failure or manual operator intervention, loss of rolling opportunities is avoided. ， Smooth operation can be realized. Furthermore, along with this, it becomes possible to reduce the fuel consumption rate of the heating furnace by an amount corresponding to the shortening of the time spent in the furnace.

[0011]

EFFECT OF THE INVENTION Since the heating furnace extraction time determination method according to the present invention is configured as described above, there are a plurality of steel materials extracted on a predetermined extraction pitch on a rolling line, and the equipment suddenly goes out. Even if the material transfer schedule fluctuates due to a failure or manual intervention by the operator, the next extraction material can be corrected by correcting the maximum value of the time difference between the predicted value and the actual value known at that time. For the subsequent furnace materials, the scheduled extraction time is corrected by the time difference between the predicted value and the actual value due to the same cause, excluding the time that has already been reflected. Operation can be realized. Further, along with this, it is possible to reduce the fuel consumption rate of the heating furnace by an amount corresponding to the shortening of the material time.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a schematic flow of a heating furnace extraction time determination method according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a schematic configuration of a hot rolling line (shared with a conventional example).

FIG. 3 is an explanatory view showing a threaded state of a hot rolling line (shared with a conventional example).

FIG. 4 is a diagram showing a schematic flow in an example of a conventional heating extraction time determination method.

[Explanation of symbols]

 1 ... Heating furnace 2 ... Rough rolling mill 3 ... Finishing rolling mill 4 ... Coiler

Claims (2)

[Claims] 1. A heating furnace extraction time determination method for determining an extraction time of a material extracted from a furnace to a rolling line in a heating furnace, and one or more detections for detecting a material transfer time on the rolling line. The time when each of the extracted materials arrives at the position is predicted and measured, and from the delay time of the measured value of the material that has arrived at each of the detection positions with respect to the predicted value, each of the detected positions is detected before that time. The heating is characterized in that the maximum value of the time obtained by subtracting the correction time based on the delay time from the predicted value of the actual measurement value of the material arrived at is added to the scheduled extraction time of the material to be extracted next. Method for determining furnace extraction time. 2. The heating furnace extraction time determination method according to claim 1, wherein the correction time is a time obtained by accumulating past correction times.