JP5185783B2 - Mill pacing control apparatus and mill pacing control method for hot rolling line - Google Patents

Description

  The present invention relates to a mill pacing control device and a mill pacing control method for a hot rolling line, and by optimizing a predetermined extraction timing for slab extraction from a heating furnace according to the state of a steel sheet being rolled. , Hot rolling that optimizes the distance between the steel sheet that has been rolled in advance and the steel sheet that has been rolled in the subsequent process (hereinafter referred to as the rolling pitch), enabling maximum production and stable operation The present invention relates to a line milpacing control apparatus and a milpacing control method.

As a conventional technique for performing mill pacing control of a hot rolling line, for example, in Patent Document 1, a scheduled slab extraction time is dynamically corrected using a difference between an actual rough rolling time and a predicted rough rolling time. A method for controlling mill pacing of a hot rolling line is disclosed. Specifically, the next extraction slab in the furnace is turned on (passed) from the extraction of each rolled material on the hot rolling line to each rolling facility including the roughing mill and the finishing rolling mill. Predict and calculate the conveyance time until it starts (starts) or turns off (ends passing). Thereafter, the extraction time of the rolled material is determined so that interference does not occur between the two rolled materials that are continuously rolled, and the actual conveyance time of the preceding rolled material is measured in the roughing mill, An error time between the actual conveyance time and the estimated conveyance time obtained in advance is obtained. After weighting this error time according to the position of the rolled material in the rough rolling mill, the scheduled extraction time when performing rolling by automatically extracting the next slab from the heating furnace is the rolling material described above. It corrects with the error time weighted according to the position in the rough rolling mill.
JP 7-290127 A

In general, the rolling pitch should be as small as possible to maximize production. However, if the rolling pitch is small, if rolling trouble occurs in the steel sheet that has been rolled in advance, the rolling speed is reduced unsteadyly, or the extracted slab is returned to the heating furnace or line Abnormal processing such as removal from the steel occurs, and the risk of lowering the production volume and reducing the yield of steel plate production and the quality of the steel plate increases.
In the prior art of Patent Document 1, there is a risk that the production amount, the yield, and the quality may be deteriorated because no consideration is given to the risk that a trouble is likely to occur in the rolled state of the steel sheet that has been rolled in advance.

  The present invention dynamically optimizes the scheduled extraction timing of the slab, taking into account the risk of trouble occurring in the rolling state of the steel sheet that has been rolled in advance, and stable operation as well as maximization of production volume. It is intended to provide a mill pacing control device and a mill pacing control method for a hot rolling line to be realized.

  In order to achieve the above object, the present invention is a mill pacing control device for a hot rolling line that determines the timing for extracting a steel material to be rolled next time from a heating furnace. Rolling state information collecting means for collecting in real time at least three types of different element information of tension fluctuation and shape change amount as rolling state information, and at least one type of three types of element information among the collected rolling state information Based on element information, rolling state quantification means that quantifies the goodness of rolling state and the likelihood of rolling trouble in the rolled steel sheet as a risk index, and information on at least steel type, finished sheet thickness, and sheet width The first extraction timing, which is the timing for extracting the steel material to be rolled next time from the heating furnace, based on the manufacturing information of the steel material including A second extraction timing that is a timing for extracting the steel material to be rolled next time from the heating furnace based on the first extraction timing determining means to be determined and the risk index quantified by the rolling state quantifying means; Extraction timing determining means, and extraction timing correcting means for correcting the determined first extraction timing based on the determined second extraction timing.

According to the present invention, the goodness of the rolled state in the rolled steel sheet and the ease of occurrence of rolling trouble can be quantified as a risk index, so the rolled state of the steel sheet that has been rolled before the risk index is good. If the risk index indicates a state where trouble is likely to occur, the slab extraction start timing is delayed, that is, rolling is enabled. Increase the pitch. Since the rolling pitch can be controlled in this way, in the hot rolling, the next slab extraction start timing can be optimized in real time for a steel plate that may cause trouble during rolling.
Further, the frequency of abnormal processing such as returning the slab to the heating furnace or removing the slab when trouble occurs can be reduced, and the production amount, yield, and quality of the steel plate can be improved.
The present invention includes a method for controlling mill pacing of a hot rolling line.

  According to the present invention, the slab schedule extraction timing is dynamically optimized in consideration of the risk of a trouble that may occur in the rolling state of a steel sheet that has been rolled in advance, and stabilized with maximization of production. It is possible to provide a mill pacing control device and a mill pacing control method for a hot rolling line that realizes operation.

Next, a mill pacing control apparatus which is a preferred embodiment of the present invention will be described in detail with reference to the drawings as appropriate.
《Hot rolling line》
First, the configuration of a hot rolling line to which the mill pacing control device of this embodiment is applied will be described with reference to FIG. FIG. 1 is a schematic configuration diagram of a hot rolling line.
As shown in FIG. 1, a hot rolling line 500 is a hot rolling line that is mill-paced, and a slab 10 having an extraction temperature of about 1200 ° C. and a thickness of about 800 mm extracted from a heating furnace 511 is roughly rolled. Rolling is performed in the width direction by the width rolling mill 521 of the part 520, and further, rolling is performed to about 250 mm in the thickness direction by a rough rolling mill 522 including two stands. Here, the width rolling mill 521 and the rough rolling mill 522 are installed adjacent to each other.
After the rolling by the roughing mill 522, the finishing rolling unit 531 is rolled to about 1 to 10 mm in the thickness direction with five stands of F1, F2, F3, F4, and F5 of the finishing rolling unit 530. After rolling by the finish rolling mill 531, the coil is cooled to a desired coil winding temperature by the cooling equipment 541 of the cooling unit 540, and wound by a coil winding device called a downcoiler 551 of the coil winding unit 550.

Here, the slab length at the time of extraction from the heating furnace 511 is about 30 m and is rolled to about 2000 m at the time of winding, so the rough rolling in the rough rolling mill 522 and the finishing by the finish rolling mill 531 are performed. Rolling, cooling in the cooling facility 541, and coil winding in the downcoiler 551 are performed in synchronization.
The finish rolling unit 530 includes various actuators (not shown) for controlling rolling, tension meters 534 (indicated as 534A, 534B, 534C, and 534D in FIG. 1), and thickness gauges before and after each finish rolling mill 531. 535 (indicated as 535A, 535B, 535C, 535D, 535E, and 535F in FIG. 1), and based on the data from the thickness gauges 535 before and after the finish rolling mill 531 of each stand, Rolling in the thickness direction at each stand is controlled by controlling the actuator of the finish rolling mill 531, and it is possible to collect the actual value of the steel plate tension between the stands at the time of rolling from these actuators and the tension meter 534. Further, from the plate thickness meter 535, it is possible to collect the actual value of the wedge, which is the plate thickness difference between both sides in the steel plate width direction. Furthermore, a shape meter 533 is installed behind the finish rolling mill 531 at the final stage of F5, and from the shape meter 533 it is possible to collect the actual value of the shape change amount that is the quality of the steel plate shape.
Incidentally, the amount of change in shape can be measured using, for example, I-Unit based on an “elongation difference” of 1 × 10 ⁻⁵ as a unit.

《Milpacing control device》
Next, the configuration of the mill pacing control apparatus 100 will be described with reference to FIGS.
The mill pacing control device 100 is a temperature sensor (not shown) that monitors the temperature of the slab 10 (see FIG. 1) in the heating furnace 511, and an extraction mechanism 513 that extracts the slab 10 from the heating furnace 511 and sends it to the rough rolling unit 520. A process computer that receives a signal from a sensor (not shown) for detecting the operation of the above, a shape meter 533, a tension meter 534D, a plate thickness meter 535F, etc., and outputs an operation command to the extraction mechanism 513 of the heating furnace 511 It consists of The process computer has a storage device such as a hard disk device, for example. The mill pacing control device 100 may be part of the software of the process computer that controls the entire hot rolling line 500.

FIG. 2 is a functional block diagram of the mill pacing control device of the present embodiment, FIG. 3 is an explanatory diagram of a configuration of the first extraction condition storage table in FIG. 2, and FIG. 4 is a reference rolling in FIG. FIG. 5 is an explanatory diagram of the configuration of the state quantity vector storage table, and FIG. 5 is an explanatory diagram of the configuration of the second extraction condition storage table in FIG.
As shown in FIG. 2, the mill pacing control apparatus 100 includes a first extraction timing determination unit 110, a heating furnace extraction state monitoring unit 120, an extraction start unit 130, an extraction timing correction unit 210, a rolling state information collection unit 220, a rolling State quantification means 230, second extraction timing determination means 240, manufacturing command information storage table 310, first extraction condition storage table 320, heating furnace extraction state storage table 330, buffer table 340, reference rolling state quantity vector storage table 350 includes a second extraction condition storage table 360.
The production command information storage table 310, the first extraction condition storage table 320, the heating furnace extraction state storage table 330, the buffer table 340, the standard rolling state quantity vector storage table 350, and the second extraction condition storage table 360 Specifically, the first extraction timing determining means 110, the heating furnace extraction state monitoring means 120, the extraction starting means 130, the extraction timing correcting means 210, and the rolling state information collecting means 220 are stored and stored in the storage device of the process computer. The rolling state quantification means 230 and the second extraction timing determination means 240 are functional blocks realized by the process computer executing the mill pacing control program stored in the storage device of the process computer.

(Manufacturing directive information storage table)
The production command information storage table 310 is a hot material such as the order of the steel materials to be rolled in the hot rolling line 500, the steel type of the steel material, the thickness of the slab of the steel material (also referred to as a steel slab), the finished plate thickness, and the plate width. Control information necessary for various types of control of the rolling line 500 (see FIG. 1) is stored, and in accordance with the steel type, the finished plate thickness, and the plate width, after extraction from the heating furnace 511, F1 Data necessary for predicting and calculating the time required to pass through each finish rolling mill 531 of the F5 stand and the time taken up by the downcoiler 551 to be completed is also stored.

(First extraction condition storage table and first extraction timing determination means)
The first extraction condition storage table 320 is a table in which first extraction condition information 324a (see FIG. 3) for extracting slabs from the heating furnace 511 is set in advance and stored in the storage device described above. The data includes data that makes it possible to refer to the position at which the tail end of the steel material currently being rolled passes through the hot rolling line 500 at which position the slab 10 of the next steel material can be extracted from the heating furnace 511.

FIG. 3 shows an example of the first extraction condition storage table 320. As shown in FIG. 3, the extraction condition storage table 320 has a steel type column 321 indicating “steel type class” indicating the type of steel on the leftmost side, for example, “A” indicating carbon steel or the like of a predetermined standard. And various types of steel class information 321a. In the right column of the steel type column 321, there is a plate thickness column 322 indicating “finished plate thickness class” indicating a classification of the finished plate thickness. For example, a finished plate thickness class code corresponding to a predetermined finished plate thickness range, for example, , “1”, “2”, etc., indicating the finished plate thickness class information 322a and the finished plate thickness range, for example, “1.0 to 2.0 mm”, “2.0 to 3.0 mm” Etc., and plate thickness range information 322b. In the right column of the plate thickness column 322, there are a “plate width class” indicating a division of the plate width and a plate width column 323 for display. ”,“ 2 ”,“ 3 ”..., Etc., indicating the plate width class information 323a, indicating the plate width range, for example,“ ˜1000 mm ”,“ 1000-1200 mm ”,“ 1200-1400 mm ” The width range information 323b is included. Further, on the right side of the sheet width field 323, there is a first extraction condition field 324, and the tail end of the steel material is located in the hot rolling line 500 at a position corresponding to the sheet width class information 323a. The first extraction condition information 324a indicating whether the next slab 10 of the steel material can be extracted from the heating furnace 511 at the timing of passing through is included.
As shown in FIG. 3, the first extraction condition information 324a is preset by being classified hierarchically by steel type class information 321a, finished plate thickness class information 322a, and plate width class information 323a.

  For example, the case where the steel type of the slab 505 is A, the finishing plate thickness is 1.5 mm, and the plate width is 1300 mm is assumed as the manufacturing command information of the slab 505 currently being rolled stored in the manufacturing command information storage table 310. To do. In this case, the first extraction condition information 324a indicates that the timing at which the tail end of the steel plate has passed through F5 which is the final stand of the finish rolling mill 531 is displayed as “missing steel plate tail end F5” in FIG. This is the first extraction condition that is selected.

The first extraction timing determination unit 110 receives the slab extraction signal that has detected the extraction operation of the extraction mechanism 513 from the heating furnace extraction state monitoring unit 120, starts the extraction start timer t, and manufacture command information storage table 310. Information on the slab plate thickness, steel type, finish plate thickness, and plate width of the slab 505 (see FIG. 1) that is currently rolled, and the steel type and finish plate stored in the first extraction condition storage table 320. The first slab extraction timing t ₁ for the next slab 10 waiting in the heating furnace 511 (see FIG. 1) is determined from the first extraction condition information 324a corresponding to the information on the thickness and the plate width.

At this time, the first extraction timing determining means 110 is configured to extract the slab plate thickness of the extracted slab 505 stored in the manufacturing command information storage table 310, the finished plate thickness when winding the downcoiler 551, and the rolling speed prediction pattern. from from the slab 505 is extracted from the heating furnace 511, for example, to calculate the predicted transport time t ₁ until the tail end portion of the steel sheet leaves the finishing mill 531 F5 stand, the first slab extraction timing Let t ₁ . Based on the first extraction condition information 324a, the estimated transfer time from the time when the slab 505 is extracted from the heating furnace 511 until the steel plate tail end passes through the stand of the finish rolling mill 531 is a past performance data map or the like. It can be easily calculated from The calculated first extraction timing t ₁ determined by the first extraction timing determination unit 110 is output to the extraction timing correction unit 210.

(Extraction timing correction means)
The extraction timing correction unit 210 is input with the _first extraction timing t ₁ from the first extraction timing determination unit 110, and thereafter, the second extraction timing determination unit 240 receives the second extraction at a constant period Td. For example, when the timing t ₂ is input and, for example, the first extraction timing t ₁ or the extraction timing t ₂ that is later than the _second extraction timing t ₂ is input, This is output to the extraction starter 130 as the corrected extraction timing t_discharge, and updated and stored in the storage unit 210a as the corrected extraction timing t_pre.
Detailed functions of the extraction timing correction unit 210 will be described in detail with reference to the flowcharts shown in FIGS.

(Heating furnace extraction state monitoring means)
The heating furnace extraction state monitoring means 120 periodically detects a slab extraction enable / disable state signal from the heating furnace 511, for example, the temperature of the slab 10 (see FIG. 1) to be extracted next, and the heating furnace extraction state storage table. Stored in 330. Then, the steel type of the slab 10, the slab plate thickness, and the like are referred to from the manufacturing command information storage table 310, and the state of the slab 10 stored in the heating furnace extraction state storage table 330 is viewed from the side of the heating furnace 511. It is determined whether or not the slab 10 can be extracted, and a signal indicating the result of extraction availability determination is output to the extraction starter 130.
In addition, the heating furnace extraction state monitoring unit 120 receives the start of the extraction start timer t by the first extraction timing determination unit 110, and the slab 505 that has been heated and extracted in the heating furnace 511 is extracted. The slab extraction enable / disable state signal stored in the heating furnace extraction state storage table 330 is cleared.

(Extraction start means)
The extraction activation unit 130 receives the extraction timing t_discharge from the extraction timing correction unit 210 after the first extraction timing determination unit 110 starts the extraction activation timer t, and then receives a new extraction timing t_discharge. Until a new extraction timing t_discharge is received. When the timer t reaches the latest extraction timing t_discharge, a signal indicating whether extraction is possible is determined from the heating furnace extraction state monitoring means 120. When the timer t is a signal indicating that extraction is possible, the extraction start signal is It transmits to the extraction mechanism 513.
If the timer t reaches the extraction timing t_discharge, and the signal indicating whether extraction is possible from the heating furnace extraction status monitoring means 120 is a signal indicating that extraction is not possible, extraction starts until a signal indicating that extraction is possible is received. It waits to transmit a signal to the extraction mechanism 513 of the heating furnace 511.

(Rolling state information collection means)
The rolling state information collecting means 220 is provided in the finish rolling unit 530 (see FIG. 1), for example, the steel plate tension between the stands measured by the actuators of the finish rolling machines 531 and 531 of the F4 stand and the F5 stand, or The steel plate tension between the stands measured by the tension meter 534D disposed between the F4 stand and the F5 stand, and the elongation difference measured by the shape meter 533 installed on the downstream side of the finish rolling mill 531 of the F5 stand. Then, the wedges measured by the thickness gauge 535F are periodically collected and temporarily stored in the buffer table 340. Then, when a predetermined number of steel sheet tension, elongation difference rate, and number of wedge data sets are stored in the buffer table 340, the steel sheet tension fluctuation σ, average elongation difference rate (I-Unit), and average wedge (μm) And is output to the rolling state quantification means 230 as the rolling state information at the above-described constant period Td.
In the following, the fluctuation of the steel sheet tension (standard deviation at a predetermined sampling number of the steel sheet tension) σ, the average elongation difference (I-Unit), and the average wedge (μm) as rolling state information are simply referred to as “tension fluctuation σ ”,“ Elongation Difference (I-Unit) ”, and“ Wedge (μm) ”.

(Rolling state quantification means and reference rolling state quantity vector storage table)
The rolling state quantifying means 230 detects the detected rolling state quantity vector X _(t based on the tension fluctuation σ, the elongation difference (I-Unit), and the wedge (μm), which are rolling state information input from the rolling state information collecting means 220. ₎ Is generated. The detected rolling state quantity vector X _(t) is a three-dimensional vector having three components: tension fluctuation σ, elongation difference (I-Unit), and wedge (μm).

The rolling state quantifying means 230 is hierarchically grouped by steel grade class, finishing plate thickness class, and plate width class in the reference rolling state quantity vector storage table 350, and is set and stored in advance based on the results. Based on the standard rolling state quantity vector Qi and the detected rolling state quantity vector X _(t) , the rolling state of the steel sheet being rolled is quantified to set a risk index. The rolling state quantification means 230 selects a predetermined number of reference rolling state quantity vectors Qi (= q _j ) as the risk index from the one having the smallest absolute value of the difference vector from the detected rolling state quantity vector X _(t). The selected reference rolling state quantity vector Qi and the detected rolling state quantity vector X _(t) are output to the second extraction timing determining means 240.

FIG. 4 shows an example of the standard rolling state quantity vector. As shown in FIG. 4, the standard rolling state quantity vector Qi is configured as a set of individual tables 351a, 351b,..., 352a, 352b,... Hierarchically grouped by steel type, finish sheet thickness class, and sheet width class. ing. The grouping hierarchically by the steel type, finish sheet thickness class, and sheet width class is made consistent with the hierarchical structure of the first extraction condition storage table 320 shown in FIG. 3, for example, the steel type “A”. In the individual table 351a for the finishing plate thickness class “1” and the plate width class “1”, the reference rolling state quantity vectors Q1, Q2, Q3, Q4,..., Qp are set. Similarly, in the individual table 352a for the steel type “B”, the finished sheet thickness class “1”, and the sheet width class “1”, the reference rolling state quantity vectors Q′1, Q′2, Q′3, Q′4 ..., Q'p is set. Hereinafter, the standard rolling state quantity vector is collectively referred to as a standard rolling state quantity vector Qi.
Although not shown in FIG. 4, each standard rolling state quantity vector Qi has, for example, a combination of a steel type code, a finished plate thickness class code, and a plate thickness code as a code code. A combination of the serial number of the reference rolling state quantity vector is added for identification. This is referred to as a standard rolling state quantity vector identification code.
Further, although the reference rolling state quantity vector storage table 350 is not displayed in FIG. 4, the plate thickness range information 322b and the plate width range information 323b are stored in the same manner as the first extraction condition storage table 320 shown in FIG. , And corresponding to the finished sheet thickness class and the sheet width class, and the intended standard rolling from the steel grade, finished sheet thickness, and sheet width for the steel slab being rolled stored in the production command information storage table 310 The state quantity vector Qi is configured to be searchable.

The normative rolling state quantity vector Qi is a three-dimensional vector having three components: tension fluctuation σ, elongation difference (I-Unit), and wedge (μm), similarly to the detected rolling state quantity vector X _(t). .
Then, both the reference rolling state quantity vector Qi and the detected rolling state quantity vector X _(t) are smaller in component tension fluctuation σ, elongation difference rate (I-Unit), and wedge (μm), that is, closer to the origin. It shows that the rolling state is better. For example, in the reference rolling state quantity vector Q1 closest to the origin 0, the components of the tension fluctuation, the wedge, and the elongation difference rate are compared with the components of the other reference rolling state quantity vectors Qi (i = 2, 3,..., P). Therefore, it can be said that it is better than the steel plate state expressed by other standard rolling state quantity vectors Qi (i = 2, 3,..., P). On the contrary, the standard rolling state quantity vector Qp farthest from the origin 0 causes more trouble in the steel sheet than the steel sheet state expressed by the other standard rolling state quantity vectors Qi (i = 2, 3,..., P−1). It is highly possible.

(Second extraction timing determination means and second extraction condition storage table)
As shown in FIG. 5, the second extraction condition storage table 360 includes a reference rolling state quantity vector No. A vector identification code column 361 displaying the above-described reference rolling state quantity vector identification code and a corresponding “extraction condition Ci (Qi)” and display extraction condition column 362 are prepared. For example, when the reference rolling state quantity vector Qi corresponding to the above-described steel type “A”, finished sheet thickness class “1”, and sheet width class “1” is taken as an example, the reference rolling state quantity vector identification code is illustratively shown. When “vector Q1”, “vector Q2”,..., “Vector Qp” are displayed, the corresponding extraction conditions Ci (Qi) are “steel plate tail end F1 missing”, “steel plate tail end F2 missing”,. "Down coiler winding complete".
For example, when the reference rolling state quantity vector Qi is arranged in the vector space as shown in the individual table 351a on the upper side of FIG. 4, the reference rolling state quantity vector Q1 is close to the origin, and thus the reference rolling state quantity vector Q1. Is an index when the rolling state is good. Therefore, in FIG. 5, as the second extraction condition C1 (Q1) corresponding to the reference rolling state quantity vector Q1, the tail end of the steel sheet being rolled corresponding to the extraction at an early timing is the first stand of the finish rolling mill 531. It is defined at the timing when (F1) is passed. Further, since the rolling state corresponding to the reference rolling state quantity vector Q2 is more likely to cause trouble in the steel plate than the rolling state corresponding to the reference rolling state quantity vector Q1, the extraction corresponding to the reference rolling state quantity vector Q2 is performed. The condition C2 (Q2) is defined at a timing when the steel plate tail end comes off the second stand (F2) of the finish rolling mill 531 which is slower than the extraction condition C1 (Q1) corresponding to the reference rolling state quantity vector Q1.

The second extraction timing determination unit 240 is configured to select a predetermined number of reference rolling state quantity vectors Qi and a detected rolling state quantity vector X _(t) selected from the rolling state quantification means 230, and a predetermined number of reference rolling state quantities. Based on the extraction condition Ci (Qi) acquired from the second extraction condition storage table 360 with reference to the vector Qi, the second extraction timing t ₂ is determined and output to the extraction timing correction means 210.
A detailed method of determining the second extraction timing t ₂ in the second extraction timing determination means 240 will be described later in the description of the flowcharts shown in FIGS.

(Overall flow chart)
Next, the overall control of the extraction timing setting in the milpacing control apparatus 100 will be described with reference to FIGS. 1 and 2 as appropriate with reference to FIG. FIG. 6 is a flowchart showing a flow of overall control of extraction timing setting in the mill pacing control apparatus.
In step S01, the first extraction timing determination unit 110 sends the steel slab from the heating furnace 511 based on a signal from a sensor that detects the operation of the extraction mechanism 513 of the heating furnace 511 via the heating furnace extraction state monitoring unit 120. Check whether it has been extracted (“Extract steel slab from the heating furnace?”).
If Yes in step S01, the process proceeds to step S02. If No, step S01 is repeated. In step S02, the first extraction timing determination means 110 refers to the manufacturing command information storage table 310, and extracts the steel type information of the slab, the finished plate thickness class information, the plate width class information, and the slab plate thickness information. And a first extraction timing t ₁ of a steel slab to be extracted next to the extracted steel slab is obtained by referring to the first extraction condition storage table 320 (“the first of the next steel slabs” get the extraction timing t ₁ of "). The acquired first extraction timing t ₁ is output to the extraction timing correction unit 210. Next, in step S03, the first extraction timing determination unit 110 starts the extraction start timer t.

In step S04, the rolling state information collecting unit 220 acquires rolling state information. The acquired rolling state information is output to the rolling state quantifying means 230. Details of step S04 will be described in detail with reference to the flowchart shown in FIG.
In step S05, the rolling state quantification unit 230 and the second extraction timing determination unit 240 calculate the _second extraction timing t2 based on the rolling state information acquired in step S04. Details of step S05 will be described in detail with reference to the flowcharts shown in FIGS.
In step S06, the extraction timing correction unit 210 corrects the extracted timing based on the second extraction timing t ₂ calculated in step S05. The corrected extraction timing t_discharge is output to the extraction starter 130.

In step S07, the extraction activation unit 130 checks whether or not the extraction activation timer t has reached the corrected extraction timing t_discharge (“corrected extraction timing reached? T ≧ t_discharge”). If Yes in step S07, the process proceeds to step S08. If No, the process returns to step S04, and the processes from step S04 to step S07 are repeated.
In step S08, the extraction starting unit 130 checks whether or not the next steel slab 10 can be extracted based on the signal indicating the extraction availability determination result from the heating furnace extraction state monitoring unit 120 (“heating furnace state confirmation?”). If the next steel slab 10 can be extracted (Yes) in step S08, the process proceeds to step S09. If not extracted (No), the process returns to step S04, and the processes from step S04 to step S08 are repeated.

  In step S09, the extraction starting unit 130 transmits an extraction start signal to the heating furnace 511. In step S10, the extraction starter 130 resets the extraction start timer, ends a series of extraction controls, returns to step S01, and repeats the control of the extraction timing for the next steel slab.

(Flow of control for obtaining rolling state information)
Next, the flow of control for obtaining rolling state information in the rolling state information collecting means 220 will be described with reference to FIGS.
FIG. 7 is a flowchart showing a flow of control of acquisition of rolling state information in the rolling state information collecting means.
In step S21, the number of samplings N = 0 is reset, and the buffer table 340 is reset. Specifically, the steel plate tension between the stands previously measured by the actuators of the finish rolling mills 531 and 531 of the F4 stand and the F5 stand, or the tension meter 534D disposed between the F4 stand and the F5 stand was measured. The steel plate tension between the stands, the differential elongation measured by the shape meter 533 installed on the downstream side of the finish rolling mill 531 of the F5 stand, and the sampling results of N sets of wedges measured by the plate thickness meter 535F. The data stored in the buffer table 340 is cleared.

In step S22, for example, a wedge, a steel plate tension from the tension meter 534D, and a shape change amount (elongation difference rate) from the shape meter 533 are acquired from the thickness meter 535F at a predetermined sampling cycle. Then, the data is written in the buffer table 340 (“the steel sheet thickness shape, tension, and shape change amount (elongation difference) of the finish rolled portion is acquired and written in the buffer table”).
In step S23, N = N + 1 is set and the number of samplings is added by one. In step S24, it is checked whether or not the sampling count N is equal to or greater than a predetermined value Nmax (N ≧ Nmax?). If the number of samplings N is equal to or greater than Nmax (Yes), the process proceeds to step S25. If the number of samplings N is less than Nmax (No), the process returns to step S22 and the sampling is repeated.

In step S25, the average thickness gauge (wedge), the tension fluctuation σ, and the average shape change amount (elongation difference) are calculated. Specifically, an average value of Nmax sheet thickness gauges (wedges) stored in the buffer table 340, Nmax tension fluctuation (standard deviation of steel sheet tension) σ, Nmax elongation difference rate (I− The average value of (Unit) is calculated.
In step S26, the calculated average of thickness gauge (wedge), tension fluctuation σ, and average of shape change amount (elongation difference) are output to the rolling state quantification means 230 as rolling state information. In the following, as described above, the average thickness gauge (wedge) and the average shape change amount (elongation difference rate) are simply “thickness gauge (wedge)” and “shape change amount (elongation difference rate)”. Called.
Steps S21 to S26 are repeated at a constant cycle, for example, at the cycle Td for calculating the _second extraction timing t ₂ described above.
Incidentally, the thickness gauge (wedge), tension fluctuation σ, and shape change amount (elongation difference rate) included in the rolling state information correspond to “element information constituting rolling information” described in the claims.

(Flow of control for correction of extraction timing based on _second extraction timing t ₂ )
Next, the second extraction timing in the rolling state quantification means 230, the second extraction timing determination means 240, and the extraction timing correction means 210 as appropriate with reference to FIGS. 1 and 2 with reference to FIGS. A flow of control of determination and correction of extraction timing will be described.
8 and 9 are flowcharts showing the flow of control of the second extraction timing determination and the extraction timing correction in the rolling state quantification means, the second extraction timing determination means, and the extraction timing correction means. Is an explanatory diagram of a difference vector Rti between the normative rolling state quantity vector Qi and the detected rolling state quantity vector X _(t), and FIG. 11 is an explanatory diagram of the extraction timing correction result.
In the flowchart, steps S36 to S46 are performed at a constant cycle Td.

In step S31, the extraction timing correction means 210 checks whether it has received a first extraction timing t _1. If received (Yes), the process proceeds to step S32. If not (No), step S31 is repeated.
In step S <b> 32, the rolling state quantification unit 230 acquires the manufacturing command information (steel type, finished plate thickness, and plate width) currently being rolled from the manufacturing command information storage table 310. In step S33, the rolling state quantification means 230 reads the reference rolling state quantity vector Qi (i = 1, 2, 3, 3) corresponding to the manufacturing command information of the steel material currently rolled from the reference rolling state quantity vector storage table 350. ..., p) are acquired in a predetermined number.
In step S34, the extraction timing correction means 210, since the state immediately after receiving the first extraction timing t ₁ from the first extraction timing deciding means 110, and T_pre = t ₁ in the storage unit 210a, in step S35, Output t_discharge = t ₁ to the extraction starter 130. Thereafter, the process proceeds to step S36.

In step S <b> 36, the rolling state quantifying unit 230 checks whether or not the rolling state information has been acquired from the rolling state information collecting unit 220. If the rolling state information has been acquired (Yes), the process proceeds to step S37, and if not acquired (No), step S36 is repeated.
In step S37, the rolling state quantification means 230 generates a detected rolling state quantity vector X _(t) based on the rolling state information. This detected rolling state quantity vector X _(t) is a three-dimensional vector having three components: tension fluctuation σ, wedge, and elongation difference. In step S38, the rolling state quantifying means 230 obtains a predetermined number m, for example, three reference rolling state quantity vectors q _i having a small absolute value of the difference vector Rti from the detected rolling state quantity vector X _(t). select ( "select smaller the m norms rolling state vector q _j absolute value of the difference vector Rti between the detected rolling state vector X _(t)").
This step S38 corresponds to “quantitating as a risk index the goodness of the rolled state and the ease of rolling trouble in the rolled steel sheet” described in the claims.
As shown in FIG. 10, the end points of the predetermined number p of reference rolling state quantity vectors Qi (i = 1, 2, 3, 4,..., P) acquired in step S33 are marked with a circle and a hatched line. The difference vector Rti (i = 1, 2, 3, 4,..., P) is obtained when the end point of the detected rolling state quantity vector X _(t) generated in step S37 is indicated by the symbol ●. A predetermined number m, for example, three are selected in order from the smallest absolute value of the difference vector, and the difference vectors are set to r _t1 (= Rt2), r _t2 (= Rt3), r _t3 (= Rt4), The corresponding standard rolling state quantity vectors are q ₁ (= Q2), q ₂ (= Q3), and q ₃ (= Q4). These selected reference rolling state quantity vectors q ₁ , q ₂ , q _{3 and the} difference vectors r _t1 , r _t2 , r _t3 are output to the second extraction timing determining means 240.
Incidentally, the above-mentioned reference rolling state quantity vector identification code is added to the reference rolling state quantity vectors q ₁ , q ₂ , q ₃ and is output to the second extraction timing determination means 240.

In step S39, the second extraction timing determination means 240 performs _second extraction on the extraction conditions Cj (q _j ) corresponding to the q ₁ , q ₂ , and q _{3 reference} rolling state quantity vectors selected in step S38. Obtained by referring to the condition storage table 360. The extraction condition Cj (q _j ) can be easily acquired from the second extraction condition storage table 360 by the reference rolling state quantity vector identification code added to the reference rolling state quantity vectors q ₁ , q ₂ , q ₃ .
In step S40, the second extraction timing determining means 240 sets the transport time Tj (j = 1, 2,..., M) of the steel material currently being rolled corresponding to the m extraction conditions Cj (q _j ). calculate. This transport time Tj is determined by heating the slab 505 from the extracted slab plate thickness of the slab 505 stored in the manufacturing command information storage table 310, the finished plate thickness at the time of winding the downcoiler 551, and the rolling speed prediction pattern. This is the estimated time from the extraction from the furnace 511 until the tail end portion of the steel plate passes the position described in the extraction condition Cj (q _j ). From the time when the slab 505 is extracted from the heating furnace 511, the predicted transport time Tj until the steel plate tail end passes through each stand of the finish rolling mill 531 and the predicted transport time Tj until the steel sheet is wound around the downcoiler 551 are past. Can be easily calculated from the actual result data map.
Here, the extraction condition Cj (q _j ) acquired with reference to the second extraction condition storage table 360 and the predicted transport time Tj calculated based on the extraction condition Cj (q _j ) Corresponds to “timing timing data”.
After step S40, the process proceeds to step S41 according to the connector (B).

ただし、Ｗｊ：差分ベクトルｒ_tj（ｊ＝１，２，…，ｍ）に対する重みである。ここで、Ｗｊ≦Ｗｊ＋１であり、例えば、選択されたｍ個の規範圧延状態量ベクトルｑ₁，ｑ₂，ｑ₃，…，ｑ_mが原点０から遠ざかれば遠いほど重みＷｊの値は大きくなるように設定してある。 In step S41, the second extraction timing determination unit 240 calculates the second extraction timing t ₂ by the following equation (1). And it outputs to the extraction timing correction means 210.

Where Wj is a weight for the difference vector r _tj (j = 1, 2,..., M). Here, a Wj ≦ Wj + 1, for example, m-number of norms rolling state vector q _1, which is selected, q _2, q _3, ..., the value of the weight Wj as q _m is further the turn away from the origin 0 is greater It is set to become.

In step S42, the extraction timing correction unit 210, a second extraction timing t ₂ calculated in step S41 to check whether T_pre larger than that stored in the storage unit 210a (t_pre <t _2). If extraction timing t ₂ is greater than t_pre (Yes), the process proceeds to step S43, otherwise (No), the process proceeds to step S36 in accordance connector (A). That is, the process returns to step S36 without correcting the extraction timing.
In step S43, the extraction timing correction means 210 acquires the elapsed time Δt from the extraction of the steel slab 505 (see FIG. 1) currently being rolled to the present. This is the timing of the extraction start timer t itself. In step S44, the extraction timing correction unit 210 calculates the correction extraction timing (t_comp = t ₂ −Δt). In step S <b> 45, the extraction timing correction unit 210 updates and outputs the extraction timing to the extraction activation unit 130. Then, in step S46, the extraction timing correcting means 210, t_pre = t ₂ and is stored and updated in the storage unit 210a.

Next, referring to FIG. 11, a time chart at the time of extraction timing correction is shown. First, in slabs is extracted from the heating furnace 511 timing, the first extraction timing deciding means 110, to determine a first extraction timing t ₁ is a timing of the next slab extraction, the extraction timing correction unit 210 And output to the extraction starting means 130 as t_discharge = t ₁ . The extraction timing correction unit 210 causes the storage section 210a stores and holds as t_pre = t _1.
Thereafter, the state of the steel sheet currently being rolled is monitored by the rolling state information collecting unit 220, and the rolling state information is output to the rolling state quantifying unit 230 at a period Td. In response to this, the rolling state quantification means 230 and the second extraction timing determination means 240 generate a detected rolling state quantity vector X _(t) from the rolling state information, and detect the detected rolling state quantity as a risk evaluation index. A predetermined number of standard rolling state quantity vectors Qi having a small difference from the vector X _(t) are selected, the second extraction timing t ₂ is calculated, and output to the extraction timing correction means 210. Extracting timing correction unit 210 receives the second extraction timing grayed t _2, compared with the values of t_pre stored in the storage unit 210a, when towards the second extraction timing grayed t ₂ is large, The new t_discharge = t ₂ is corrected and output to the extraction starter 130 to update the extraction timing, and the storage unit 210a is updated and stored with t_pre = t ₂ .
After that, when the value of the second extraction timing t ′ ₂ newly calculated at the period Td by the rolling state quantification means 230 and the second extraction timing determination means 240 is larger than t_pre, again and again,. The new t_discharge = t ₂ is corrected and output to the extraction starter 130 to update the extraction timing, and the storage unit 210a is updated and stored with t_pre = t ′ ₂ .

In the flowchart of FIG. 9 of the present embodiment, steps S43 and S44 are not necessarily required and are displayed so as to easily correspond to the description of FIG. 11. Steps S43 and S44 are deleted, and steps S43 and S44 are deleted. There is no problem even if S45 is simply set to “extraction timing updated output (t_discharge = t ₂ )”.

As described above, when the rolling state amount of the steel plate being rolled becomes unstable, the extraction timing correction unit 210 again corrects the extraction timing again. Thereafter, the correction of the extraction timing is repeated as necessary until the rolling of the steel plate currently being rolled is completed.
By doing in this way, when the rolling state of the steel material being rolled in advance is in a state where trouble is likely to occur, the value of t_discharge already output from the extraction timing correcting unit 210 to the extraction starting unit 130 is The slab extracted once from the heating furnace 511 is corrected to a large value, for example, the time corresponding to the timing when the tail end of the steel plate has passed through the finish rolling mill 531 of the F5 stand, or the timing when the coiling is completed in the downcoiler 551. Inconvenience such as returning to the heating furnace 511 can be prevented.
When rolling state of the steel during rolling the preceding is good, because the first extraction timing t ₁ is used as it is, if the rolling condition is good is packed rolling pitch, it is efficient production .
Further, the frequency of abnormal processing such as returning the slab to the heating furnace or removing the slab when trouble occurs can be reduced, and the production amount, yield, and quality of the steel plate can be improved.

Further, as in the present embodiment, three-dimensional vectors having these as components are obtained by using three pieces of element information of sheet thickness gauge (wedge), tension fluctuation σ, and shape change amount (elongation difference rate) as rolling state information. As the detected rolling state quantity vector X _(t) , a plurality of reference rolling state quantity vectors Qi previously grouped in a hierarchical structure of steel types, finished sheet thickness classes, and sheet width classes are used as reference rolling state quantity vectors Q1 with good rolling conditions. To a reference rolling state quantity vector Qp that is likely to cause a rolling trouble, and by selecting a reference rolling state quantity vector Qi having a small absolute value of a difference vector from the detected rolling state quantity vector X _(t) , It can be easily quantified as a rolling state risk index.
And the steel plate tail currently being rolled at the timing of extraction based on the extraction condition Cj (q _j ) corresponding to the selected standard rolling state quantity vector q _j (= Qi) (j = 1, 2,..., M). The second extraction timing t ₂ suitable for the selected standard rolling state quantity vector q _j can be easily calculated by calculating the end position time (conveying time Tj).

Furthermore, the extraction timing correction means 210 is a change in the rolling state of the steel sheet being rolled, and the second extraction timing t ₂ is changed to the first extraction timing t ₁ or the repetition of the previous correction. Even if a time shorter than t_pre stored in the storage unit 210a is calculated, the extraction timing correction unit 210 does not adopt it conservatively as shown in step S42 (see FIG. 9) of the flowchart. It is possible to prevent the failure of the control to erroneously extract the next slab early when there is a good and worsening wave in the rolling state.

In the present embodiment, the rolling state quantity information uses three pieces of information of tension fluctuation σ, wedge, and elongation difference rate (I-Unit) to detect the rolling state goodness and the ease of occurrence of rolling troubles. The quantity vector X _(t) is generated, and the reference rolling state quantity vector Qi to be compared with the detected rolling state quantity vector X _(t) is also a component of the tension fluctuation σ, the wedge, and the elongation difference rate (I-Unit). However, it is not limited to this.
Both the detected rolling state quantity vector X _(t) and the reference rolling state quantity vector Qi have the same components as any one of the three pieces of information of tension fluctuation σ, wedge, elongation difference rate (I-Unit), or Any two identical components may be used.
Moreover, in this embodiment, although it was set as the wedge obtained with the plate | board thickness meter 535F as plate | board thickness shape, it is not limited to it. When a plurality of plate thickness gauges 535F arranged in the plate width direction are used, the thickness distribution σ _t in the plate width direction may be used as element information of the plate thickness shape.

In this embodiment, an example in which the mill pacing control device 100 of the hot rolling line 500 determines the extraction timing of the steel material from the heating furnace 511 is shown. However, depending on the configuration of the hot rolling line, the steel material is extracted from the tunnel furnace. There is a case where the timing to perform is determined. At this time, the present invention can be applied with the same configuration.
Moreover, in this embodiment, the rolling state of the steel plate currently rolled is shown as an example in which the reference rolling state quantity vector Qi is selected in the vector space using the reference rolling state quantity vector Qi and quantified as a risk index. However, other methods such as a method of quantifying using a rule such as “IF tension fluctuation large AND shape I-Unit large The rolling condition is bad” are also conceivable.
In the present embodiment, a tandem rolling facility composed of a plurality of stands is described as an example, but application to a reciprocating rolling facility (Steckel mill rolling facility) using a single stand is also possible.

  It can be widely applied to mill pacing control in hot rolling lines.

It is a schematic block diagram of a hot rolling line. It is a functional block diagram of the mill pacing control apparatus of this embodiment. It is explanatory drawing of a structure of the 1st extraction condition storage table in FIG. It is explanatory drawing of a structure of the normative rolling state quantity vector storage table in FIG. It is explanatory drawing of a structure of the 2nd extraction condition storage table in FIG. It is a flowchart which shows the flow of the whole control of the setting of the extraction timing in a mill pacing control apparatus. It is a flowchart which shows the flow of control of acquisition of the rolling state information in a rolling state information collection means. It is a flowchart which shows the flow of control of the 2nd extraction timing determination in the rolling state quantification means, the 2nd extraction timing determination means, and the extraction timing correction means, and the correction of extraction timing. It is a flowchart which shows the flow of control of the 2nd extraction timing determination in the rolling state quantification means, the 2nd extraction timing determination means, and the extraction timing correction means, and the correction of extraction timing. It is explanatory drawing of the difference vector Rti of the normative rolling state quantity vector Qi and the detected rolling state quantity vector X _(t) . It is explanatory drawing of the correction result of extraction timing.

Explanation of symbols

10 Slab (steel slab)
DESCRIPTION OF SYMBOLS 100 Mil pacing control apparatus 110 1st extraction timing determination means 120 Heating furnace extraction state monitoring means 130 Extraction start-up means 210 Extraction timing correction means 210a Memory | storage part 220 Rolling state information collection means 230 Rolling state quantification means 240 Extraction timing determination means 310 Manufacturing command information storage table 320 First extraction condition storage table 321a Steel type class information 322a Plate thickness class information 322b Plate thickness range information 323a Plate width class information 323b Plate width range information 324a Extraction condition information 330 Heating furnace extraction state storage table 340 Buffer Table 350 Standard rolling state quantity vector storage table 360 Second extraction condition storage table 361 Vector identification code column 500 Hot rolling line 505 Slab (steel slab)
511 Heating furnace 513 Extraction mechanism 520 Rough rolling section 521 Width rolling mill 522 Rough rolling mill 530 Finish rolling section 531 Finish rolling mill 533 Shape gauges 534A, 534B, 534C, 534D Tensiometers 535A, 535B, 535C, 535D, 535E, 535F Thickness gauge 540 Cooling section 541 Cooling equipment 550 Coil winding section 551 Downcoiler

Claims (7)

A heating furnace for heating the steel material to a high temperature, a width rolling machine for rolling the steel material extracted from the heating furnace in the width direction, a rough rolling machine for rolling in the thickness direction, and further rolling the rolled steel material in the thickness direction. A hot rolling line equipped with a finish rolling mill that produces thin steel plates, a cooling facility that cools the steel material rolled by the finish rolling mill, and a downcoiler that winds the cooled steel material to form a hot rolled coil. On the other hand, in the mill pacing control device of the hot rolling line that determines the timing for extracting the steel material to be rolled next time from the heating furnace,
Rolling state information collecting means for collecting, in real time, at least three types of different pieces of element information of sheet thickness shape, tension fluctuation and shape change amount of steel material currently rolled by the finish rolling mill,
Based on at least one type of element information in the three types of element information of the collected rolling state information, the goodness of the rolling state in the rolled steel sheet and the likelihood of occurrence of rolling troubles are used as risk indicators. Rolling state quantification means for quantification;
First extraction timing determination for determining a first extraction timing that is a timing for extracting the steel material to be rolled next time from the heating furnace based on manufacturing information of the steel material including information on at least steel type, finished plate thickness, and plate width. Means,
Second extraction timing determining means for determining a second extraction timing which is a timing for extracting the steel material to be rolled next time from the heating furnace based on the risk index quantified by the rolling state quantifying means;
A hot rolling line mill pacing control device, comprising: extraction timing correction means for correcting the determined first extraction timing based on the determined second extraction timing. The reference rolling state quantity vector indicating the goodness of the rolling state and the ease of occurrence of rolling trouble in the steel sheet being rolled, comprising at least one type of element information of the element information constituting the rolling state information, , A plurality of pre-set rolling state quantity vector storage table,
The rolling state quantifying means is the same type as the element information constituting the reference rolling state quantity vector among the types of element information constituting the rolling state information collected by the rolling state information collecting means. Based on the detected rolling state quantity vector,
2. The risk index is specified by specifying a predetermined number of the reference rolling state quantity vectors in order from the smallest absolute value of the difference from the generated detected rolling state quantity vector. Mill pacing control device for hot rolling line. The timing data of the second extraction timing is stored in advance in the second extraction condition storage table corresponding to each of the reference rolling state quantity vectors,
In the second extraction timing determination means, the predetermined number of the reference rolling state quantity vectors as the risk index specified by the rolling state quantification means is 1, and the detected rolling state information quantity vector generated 3. The hot rolling line mill pacing control apparatus according to claim 2, wherein the second extraction timing is determined based on timing data corresponding to a reference rolling state quantity vector having a smallest absolute value of the difference. The timing data of the second extraction timing is stored in advance in the second extraction condition storage table corresponding to each of the reference rolling state quantity vectors,
In the second extraction timing determination means, the predetermined number of the reference rolling state quantity vectors as the risk index specified by the rolling state quantification means is 2 or more, and each of the reference rolling specified as the risk index 3. The heat according to claim 2, wherein timing data corresponding to the state quantity vector is determined by weighted addition according to at least the magnitude of the absolute value of the difference, and is determined as the second extraction timing. Mill pacing control device for hot rolling line. The plurality of reference rolling state quantity vectors are grouped and stored by at least one of the steel type, finish plate thickness, and plate width information,
The rolling state quantifying means uses the reference rolling state quantity vector of the corresponding group, grouped by at least one of the steel type, finish plate thickness, and plate width information of the steel material currently being rolled, and the risk index. 5. The mill pacing control device for a hot rolling line according to claim 2, wherein: A heating furnace for heating the steel material to a high temperature, a width rolling machine for rolling the steel material extracted from the heating furnace in the width direction, a rough rolling machine for rolling in the thickness direction, and further rolling the rolled steel material in the thickness direction. For a hot rolling line equipped with a finish rolling mill that produces thin steel plates, a cooling facility that cools the steel rolled by the finish rolling mill, and a downcoiler that winds the cooled steel and produces hot rolled coils. In the mill pacing control method of the hot rolling line for determining the timing for extracting the steel material to be rolled next time from the heating furnace,
The extraction timing from the heating furnace of the steel material to be rolled next time is once determined by using the manufacturing information of the steel material including information on at least steel type, finished plate thickness, and plate width,
Three types of different component information of the steel material currently being rolled by the finish rolling mill, such as sheet thickness shape, tension fluctuation and shape change amount, is collected in real time as at least rolling state information,
Based on at least one type of element information in the three types of element information of the collected rolling state information, the goodness of the rolling state in the rolled steel sheet and the likelihood of occurrence of rolling troubles are used as risk indicators. Quantified,
A method for controlling mill pacing of a hot rolling line, wherein the extraction timing once determined is corrected based on the quantified risk index.   When it is determined from the quantified risk index that the rolling state is not good or rolling trouble is likely to occur, the extraction timing determined once according to the degree is corrected in a direction to delay. A method for controlling mill pacing of a hot rolling line according to claim 6.

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