KR20050017692A - Mill pacing control method for reheating furnance - Google Patents

Abstract

PURPOSE: To provide an automatic extraction control method of reheating furnace, the method capable of uniformly maintaining quality and output per steel types and working patterns by determining return schedule of the whole rolling line considering accelerating and decelerating patterns and return schedule, thereby accurately predicting return schedule of a succeeding extraction material. CONSTITUTION: An automatic extraction control method of reheating furnace comprises a step of checking whether extraction of a work is completed or not in the reheating furnace; a step of reading information on the relevant work and operation data including operation and finish rolling setup data from a hot rolling process facility if extraction of the work is completed as results of the checking; a step of drawing up a predicted return schedule by predicting a return schedule from extraction time point of the reheating furnace to coiling completion time point through a return scheduler based on the read operation data; a step of calculating the minimum extraction pitch between two extraction materials such that the predicted return schedule satisfies restriction conditions on a rolling line; a step of determining an extraction time of a next extraction material from the calculated minimum extraction pitch and reheating furnace restriction conditions delivered from the reheating furnace; a step of drawing up an actual result return schedule by collecting return actual results on a work of which extraction is completed in the checking step; a step of detecting an error on the predicted return schedule by comparing the actual result schedule with the predicted return schedule if drawing up of the actual result return schedule is completed; a step of applying the compensated extraction time to the reheating furnace by compensating the extraction time of the next extraction material as much as the detected error; and a step of learning the predicted return scheduler such that the detected error is compensated.

Description

Mill pacing control method for reheating furnance

The present invention determines the conveyance schedule of the whole rolling line in consideration of the acceleration / deceleration pattern and conveyance schedule in each facility that is easily overlooked by the driver. The automatic extraction control method of the furnace which can be maintained easily.

In general, in the operation of the furnace in the hot rolling process, it is most important to control the temperature of the furnace and the burner. In the related art, the driver checks the heating state of the furnace at an appropriate temperature, and the operating situation of rough rolling and finishing rolling in the cab is checked. After being notified by wire or wireless, the extraction pitch of the furnace is determined based on this.

The operation mode for the furnace extraction made in the conventional hot rolling process is divided into timer mode and manual mode.

In the above, the timer mode is an operation mode that is performed during a general operation. When the furnace operator views the temperature displayed on the sequence controller controlling the furnace and the ashing time for the corresponding material, and sets the furnace extraction pitch to the extraction timer. In this case, the roughing and finishing rolling conditions are informed by the rolling mill operator and reflected in the extraction pitch decision.

Next, the manual mode is an operation mode which is executed when an abnormality occurs in the function of the furnace or a constraint occurs due to an abnormality of the rolling line, and the driver manually extracts each sheet from the furnace.

That is, conventionally, the determination of the extraction pitch of a furnace depends on the complete manual operation by the experience of a furnace operator and a rolling mill operator.

In this case, it is difficult to accurately control the degree of achieving the heating target temperature and the degree of cracking for the material to work at the optimum time in the rolling line, and also after the material is extracted from the heating furnace, the return schedule is progressed. Since the optimal working time is selected by reflecting this on the following materials, the heating furnace should be heated and extracted sufficiently to prevent the temperature shortage that may occur in the work in the rolling line. Since the operation pattern for lowering the temperature must be generated for the overheated material depending on the material, the fuel raw unit rise of the furnace, water waste due to overcooling, and the delay of the operation time occur.

In addition, depending entirely on manual work, there is a problem that a difference in quality and conveying time occurs for each driver's inclination, and thus uniform productivity cannot be obtained.

That is, it is difficult to secure optimal heating and cracking by the conventional method, and it is difficult to obtain the best yield while maintaining the quality of the material in the rolling line, and the quality deviation and output deviation occur by worker or work tank. Occurred.

The present invention has been proposed in order to solve the above-mentioned conventional problems, and an object thereof is to provide an automatic extraction control method for a furnace that automatically sets an optimum material extraction pitch according to heating conditions, rough rolling and finishing conditions of finishing rolling. To provide.

Another object of the present invention is to determine the conveyance schedule of the whole rolling line in consideration of the acceleration and deceleration pattern and conveyance schedule in each facility that the driver is easily overlooked, to accurately predict the conveyance schedule of the next extraction material to work quality and production by steel type It is to provide an automatic extraction control method of the heating furnace that can be maintained uniformly for each pattern.

As a constituent means for achieving the above object, the present invention is a heating furnace automatic extraction control method of the hot rolling process provided in the heating furnace, sizing press, rough rolling mill, finishing mill, down-coiler in order to extract the material from the heating furnace Checking completion; As a result of the check, when the extraction of one material is completed, reading operation data including information on the corresponding material and operation and finishing rolling setup data from the hot rolling facility; Creating a predicted transport schedule by predicting a transport schedule from the extraction of the furnace to the completion of the winding through a transport scheduler based on the read operation data; Calculating a minimum extraction pitch between the two extractors from the predicted transport schedule to satisfy the constraint on the rolling line; Determining an extraction time of the tea extract from the calculated minimum extraction pitch and heating constraints transferred from the heating furnace; Collecting a return record for the material extracted in the checking step to create a return return schedule; Detecting completion of a prediction return schedule when the preparation of the performance return schedule is completed; Correcting the difference extraction time of the tea extract material by the detected error and applying the same to a heating furnace; And training the prediction carrier scheduler so that the detected error is corrected.

EMBODIMENT OF THE INVENTION Hereinafter, with reference to attached drawing, the structure and operation | movement of the automatic extraction control method by this invention are demonstrated.

1 is a process diagram schematically showing a rolling line to which the automatic extraction control method according to the present invention is applied, and the rolling process includes a heating furnace 11 for heating a material to a predetermined temperature suitable for rolling, and extraction from the heating furnace 11. The sizing press 12 for adjusting the width of the raw material to the appropriate range, the roughing mill 13 to roll-roll the material passing through the sizing press 12, and the material discharged from the roughing mill 13 It consists of the finishing mill 15 to roll and the winding machine 16 which winds the coil discharged | emitted from the said finishing mill 15. As shown in FIG. At this time, a delay table for adjusting the conveying speed of the material is further provided between the roughing mill 13 and the finishing mill 14.

Then, in the rolling line as described above, the events of the roughing mill 13 and the finishing mill 15 are collected, and the performance is collected through each of the mathematical model calculators 17 and 18, and whether or not the odor is completed from the curling machine 16. Information is collected and input to a supervisor control computer (hereinafter referred to as SCC) 23, wherein the SCC 23 controls each rolling line in accordance with a work instruction from the upper calculator 20. Collecting the results of the to and delivered to the furnace automatic extraction control unit 25, the furnace automatic extraction control unit 25 performs each step of the method according to the invention, to predict the return schedule of the preceding extract, Set the extraction peak of the extraction material. The extraction peak set from the heating furnace automatic extraction control unit 25 is transferred to the heating furnace PLC 22 to drive the extractor of the heating furnace 11. In addition, the events and constraints of the furnace from the furnace PLC 22 are collected and transferred to the furnace automatic extraction control unit 25, and the time of the remaining furnace in the furnace is further controlled by the combustion control unit 24 of the furnace. The furnace automatic extraction control unit 25 is transferred to the furnace automatic extraction control unit 25, and the furnace automatic extraction control unit 25 uses the various performance data and operation data collected as described above to set the furnace extraction time, and at this time, a return corresponding to the set extraction time is returned. The time is applied to the combustion control unit 24.

The heating furnace automatic extraction control unit 25 may be implemented with a mathematical model calculator.

Figure 2 shows the installation of a hot metal detector (HMD) is installed in a typical hot rolling line (HMD).

The automatic extraction control method according to the present invention is a function of the acceleration and deceleration pattern of the speed changed by the size of the material and equipment conditions, starting from the event signal generated in the equipment and HMD of the hot rolling process, as a function of time, The extraction pitch is determined by reflecting this on the return schedule of the tea extraction material, and its detailed operation is performed as follows.

3 is a flowchart showing the overall procedure of the automatic extraction control method according to the present invention, with reference to this will be described the automatic extraction control method of the present invention.

In the heating furnace automatic extraction control method according to the present invention, the process for the extraction control for the tea extraction material is started from the time point at which the extraction of the preceding material from the heating furnace 11 is completed.

That is, when the preceding material is extracted from the heating furnace 11, the conditions (temperature, etc.) of the extracted preceding material are substituted into the rough rolling model and the finishing rolling model to calculate the rough rolling model and the finishing rolling model ( S32).

The operation data for the automatic extraction control is input from various facilities such as rolling instruction, rough rolling / steam rolling set up function, table value, and various units and types. Therefore, in the data processing step S33, the input data is prepared by converting it into a form that is easy to process in the following steps. In addition, various variables are initialized (S34). The data processing step S33 is specifically performed as shown in FIG. 4. That is, after setting the number of copies after the airborne and the number of copies after the MPC abnormality (S331), the calculated rough rolling / imaginary rolling data is read (S332), and the unit and type of the data are converted into a predetermined format (S334). ), The thermal coefficient is converted (S334). Setup abnormality processing, winding determination, and setting of various fixed values are performed (S337).

However, regarding the first process after merits, rolling stops, calculator start, and MPC function start, the first extraction is processed manually and the second material is processed in accordance with the timing of extracting the preceding material.

In particular, after abnormality, this number is counted up every calculation, but is reset to "1" in the following cases.

First, after merit, second, first, after rolling stop, second, after the down of the calculator, fourth, fourth, after the start of automatic extraction control, fifth, back to For the first material after the ashes and ashes back.

The number of times after the automatic extraction control error according to the present invention is counted up every time, but is reset when the number is reset after the automatic extraction control abnormality and when the automatic extraction control error flag is generated in the preceding material.

Next, using the information of the material processed in the data processing step (S33) (for example, the size, the passing information, etc.) and the water purification table, from the extraction of the heating furnace 11 to the winding machine 16 Predictive calculation of the movement of the steel sheet (hereinafter referred to as a transport schedule) to appear on the rolling line until the winding is completed (S34). The predictive conveyance schedule calculates the tip, tail end position, velocity, acceleration, and elapsed time from the start of extraction at the point where the acceleration or sheet thickness of the steel sheet changes. From the said conveyance schedule, the time which the steel plate of arbitrary positions on a rolling line passed after extraction of the heating furnace 11 can be calculated | required. The start of extraction is regarded as the first event, and the movement of the steel sheet from this to completion of winding is predicted. The event is basically based on a change in velocity, which is the point where the plate thickness changes. Acceleration and material thickness are proportionally constant between event i and the next event i + 1. Conversely, even if the acceleration or the headboard does not change, the change point is managed as an event. For each event, the position, velocity, acceleration, etc. of the leading and trailing edges are calculated based on the time after the start of extraction.

The calculation method may be a method of adding a change in acceleration derived by calculating the time, position, and velocity of the next event from the time, position, velocity, and acceleration determined from the previous event. In this case, the utilization is made by considering the equation of motion equation and logistics flow.

For example, the speed (VC) and the acceleration / deceleration rate (aC) of the leading edge at the forward pass and the reverse pass at the forward pass are calculated as shown in Equation 1 below. The velocity VC 'and the acceleration and deceleration rate aC' are calculated as in Equation 2 below.

Here, VR is a roll circumferential final value [m / s], VR ₀ is a roll circumferential initial value, L is a distance [m], Ar is a roll circumferential conversion acceleration / deceleration rate [m / s ² ], and f is a advance rate.

Here, Hout is the main board exit plate thickness [m], Hin is the main board entry board thickness [m], Wout is the main board exit board width [m], and Win is the main board entry board width [m].

The entry speed of each pass is shifted to the above-described VC'-PN, aC'-PN (where PN is 1 for odd pass and -1 for even pass) when metal is in.

In finishing rolling, the step speed is until the material of the first stand F1 is discharged.

Becomes

Here, LS is a synchronous stand, HR ₂ is the exit plate | board thickness of rough rolling, and V _TH is a board | plate speed. In the above, the metal in of each stand is to be the metal in the next stand as the end of each stand moves the distance between each stand, the tip speed is a metal in of the stand i h (i) / h (i + 1) times, The tip speed is invariant, the stern end acceleration is invariably zero, and the unit value is calculated from the speed and time.

At this time, the operating time of the extractor of the heating furnace is calculated by dividing the forward / ascending / retracting / falling, the calculation is performed by the width of the material for each operation step to the total value as the operating time. This is expressed as in Equation 3 below.

Here, t1 is the forward time of the extractor, t2 is the rise time, t3 is the retreat time, t4 is the fall time, and the unit is sec. W _S is the width of the material and TEXT is the operating time of the extractor.

After the extraction of the preceding material from the heating furnace 11 is completed, the return schedule of the exit table of the heating furnace 11 does not use the sizing press 12, and when working in a dummy (DUMMY) and the sizing press ( 12), each conveying pattern is as shown in Figs.

Referring to FIG. 6, when the sizing press 12 is not used, the motor accelerates to 80 mpm / s starting from the table and reaches 100 mpm / s. When the sizing press 12 is reached, the sizing press 12 is maintained. After passing, it decelerates in the table D9 and stops completely at the position of the detection sensor 101-HMD02. In the case of using the sizing press 12, as shown in Fig. 7, the speed is accelerated to 80mpm / s starting from the table, and when the speed reaches 100mpm / s, the continuous speed is maintained without deceleration.

Next, as shown in FIG. 8, the material of the sizing press 12 calculates a pattern for centering the guide located on the front surface, and results in about 5.5 seconds to 6.6 seconds in any operating condition.

Then, the workpiece takes about 2.22 seconds to reach the sensor SP-CMD-R02 from the sensor SP-CMD-R01 as shown in FIG. 10. As shown in Fig. 9, the conveying pattern in the sizing press 12 is decelerated from the front side and once stopped at the side guide centering time, and then accelerated to 90mpm / s until the pinch roll pressing time (35mpm / s) and then decelerated. do. The material passing through the pinch roll is accelerated-constant-decelerated until it reaches 60mpm at 240mpm / s again in the sizing press 12 and arrives before the press and stops once. In press, the constant speed of 20mpm / s and the acceleration / deceleration of 240mpm / s are repeated. After the final step of the material passes completely in the sizing press 12, the material accelerates until the speed reaches 60mpm.

After passing through the sizing press 12, the conveying pattern of the raw material in the roughing mill 13, as shown in Fig. 11, in the speed change of the mouth side for each pass, and in the interval between metal-in and metal-off It is largely divided into a speed change of, and in order to explain this, accelerated to 90mpm / s, roughing mill R1 is 200mpm, roughing mill R2 maintains the rolling constant at 270mpm. In addition, the tail end of the material is maintained at 90mpm during the metal-off to completely exit the rolling mill to secure the kick off distance for the next pass entry. Subsequently, the reverse pass is performed, but the operation is performed under the same conditions as the forward pass.

The method of calculating the deceleration point of the extraction speed of the roughing mill 13 divides the case where the rolling speed is below the reference speed and the case where the rolling speed is above the reference speed, and after calculating the moving distance of the entrance part necessary to reduce the rolling speed from the rolling speed to the extraction speed. Set a deceleration point within the travel distance.

In particular, in the roughing mill 13, a predetermined acceleration distance is required in order to reach the inlet speed of the next pass after the metal-off reversal, which is called a kick-off distance, which is transmitted from an upper calculator.

After the material passes through the roughing mill 13, the conveying sequence in the delay table 14 until the finishing process 15, which is the next process, is carried out when the F0 stand is used (a). ), There are two cases when not in use (b). The speed is adjusted by changing the position of the acceleration point in two stages. In the delay table 14, the second acceleration (291mpm) is performed after the first acceleration (270mpm) because of the long distance.

When using F0 after the 2nd acceleration, deceleration starts from 1 second after passing HMD114, decelerates to the front of F0 stand after HMD115, decelerates to F0 stand insertion speed (80mpm), and then cuts into CROP SHEAR (not shown). Maintaining the speed (75mpm) for cutting the head, after cutting the head portion, enters the filament rolling 15 at the F1 stand insertion speed.

If the F0 stand is not used, after the 2nd acceleration to HMD115, the F0 stand is not used. Therefore, after decelerating to the cutting speed (75mpm) and cutting the head part in the crop shear, the F1 insertion speed Pass through the finishing mill (15).

As shown in FIG. 13, the conveyance pattern in the finishing mill 15 is accelerated in the order of the stands F1-F2-F3-F4-F5-F6, since the speed varies depending on the steel type and size of the material. Only define and do not formalize speed separately. However, the transport pattern may be classified into three types according to the pattern in which the tip of the material is inserted into the winder 16. When the first pattern PATTERN1 accelerates the six stages of the stand to the stands F1 to F6, the tip is accelerated while passing through the last stand (ACC-1 RATE), and the tip of the winder 16 is bitten. Tension is applied by the speed of the winder 16 to cause a change in acceleration. Here, the acceleration changes from ACC-1 RATE to ACC-2 RATE and reaches the maximum speed (max Spd). The second pattern PATTERN2 synchronizes the speeds of the last stand and the winder 16 so that when the tip of the material passes the last stand F6, the maximum speed max spd is reached with a constant acceleration (ACC-1 RATE). do. The third pattern PATTERN3 maintains the same speed until the winder 16 is synchronized with the speed of the last stand without accelerating after the tip of the material passes the last stand. After the tip reaches the COILER, it starts accelerating with the ACC-2 RATE to reach MAX SPEED. When both ends of the material reach the crop share, the first to third patterns slightly decelerate for cutting the ends. Then, after maintaining the constant speed until the tail end of the material exits the last stand, the speed decreases when the tail end is completely removed, and when the material is completely wound on the winder 16, the speed of the material becomes zero.

At this time, as shown in Figure 14, the material does not decelerate as soon as the metal-off at the last stand, but begins to decelerate after securing a certain distance (XPOFF point) to secure the speed at the last stand.

Next, the extraction pitch depending on the constraint on the rolling line is calculated from the calculated transfer schedule (S35).

In order to smoothly convey a plurality of steel sheets in a rolling line, there are various constraints, and here, the minimum extraction pitch between two steel sheets satisfying the constraints using both the conveying schedule of the tea extract, the conveying schedule of the preceding materials, and the constraint data is used. Calculate

Then, the extraction time of the final car extraction material is determined using the difference extraction possible time due to the heating furnace constraint provided by the minimum extraction pitch and the combustion control unit 24 of the heating furnace (S36). The difference extraction time determining step (S36) is performed in order of determining the extraction time of tea, starting the setting function, and setting the neck process.The calculation of the tea extraction time includes: rolling line constraint pitch, automatic extraction mode on-off time, It is obtained by selecting the maximum value among the minimum constraints of the preset extraction pitch and adding the extraction time performance value of the preceding material. If this is expressed as an equation, Equation 4 below.

In Equation 4, Is the difference extraction time setting value, TEXT ₀ is the extraction time performance value for the preceding material, PitM calculated in the step S35 is the constraint pitch of the rolling line, PitF = TextF-Text ₀ is in the combustion control unit 24 of the furnace Pitmin is the limit of heating furnace calculated by subtracting the extraction time performance value of the preceding material from the calculated difference extraction time.

Tea extraction time set value calculated in this way The extraction starts to start the setting function.

In general, the neck (neck) process is largely divided into a heating furnace constraint net and a rolling line constraint neck, the determination of the neck process is determined as follows.

Neck = 99: Furnace neck (PitM <PitF)

= JNECKM: Rolling Pharmaceuticals Neck (PITM> = PitF)

     = 100: limit value

In the above, JNECK represents the neck process, JNECKM is the number of rolling constraints, PitM is the rolling line constraint pitch, and PitF is the heating furnace constraint pitch.

That is, the neck process is largely divided into a case in which the furnace neck is larger than the rolling line neck, a case in which the rolling line neck is larger than the furnace neck, and a case in which the two net processes fall short of the limit value, and are determined as described above.

The extraction time set as described above is transferred to the PLC 22 of the heating furnace 11 to operate the furnace extractor at the set extraction time to extract the tea extract material (S37).

At the same time, in accordance with the movement of the preceding material extracted from the heating furnace 11, the performance conveyance schedule on a rolling line is created (S39).

This is to collect the performance time of the various events (for example, on / off of the material detection sensors (HMD) shown in Figure 2, on / off of the rough rolling mill / rolling mill, etc.) that appear on the rolling line during the transfer of the preceding material Is created. In other words, when an event occurs by an input / output data list, the event number and the event occurrence time are stored in association with the location, and data is collected for the same location, thereby creating a performance return schedule.

Differences occur between all predicted return schedules and historical return schedules. The difference between the predicted value and the performance value is caused by the error of input data such as the length of the material, the prediction error of the material thickness, the slip of the steel sheet on the table, the speed by the driver's intervention and the acceleration change.

Therefore, when the performance return schedule from the extraction of the furnace to the winding of the heating material is completely prepared as described above, the performance return schedule thus prepared is compared with the predicted return schedule calculated for the material. (S40). In other words, the error of the performance value of the predicted return schedule is detected.

Then, the difference extraction time determined in step S36 is corrected for the difference extracting material based on the comparison (S41). The difference extraction time is modified by taking into account the difference time of extraction, preceding material extraction performance value, rolling line constraint pitch, conveyance schedule of the furnace constraint pitch, and dynamic correction amount. This detects an error with the performance value for the predicted value at a predetermined check point, corrects the difference extraction time by the error, and restarts the extractor of the heating furnace. The checkpoint is, for example, the time of material injection in the roughing mills R1 and R2, the material discharge and the time of material injection into the first stand F1 of the finishing mill, and the modification of the tea extract is from the start of extraction of the preceding extract. The above events occur up to the start of the tea extract. At the time of forced extraction by the driver, the time extracted by the driver is calculated to absorb the time difference at the time of completion extraction.

The dynamic correction step (S41) will be described in more detail. When the steel sheet i generates an event at the checkpoint j, and uses the information of the steel sheet k existing upstream than the steel sheet i, The predicted error of the checkpoint j is obtained by subtracting the dynamic correction amount of the tea extract and the equipment constraint margin of the preceding material, as shown in Equation 5 below. However, the maximum value determined by the recognizable event is employed within the above-described range (from the start of extraction of the preceding material to the extraction of the tea extract).

In the above, k is the tea extract material located upstream of the steel sheet i, Is the dynamic correction amount of steel plate k, which is the tea extract, αDk is the equipment constraint margin of steel plate k, Is the forecast error of the checkpoint, which is the performance time minus the forecast time.

At this time, it is impossible to compare the prediction and performance return schedules for the materials with automatic extraction abnormalities (when the prediction transport schedule cannot be achieved due to the rough rolling and the finishing rolling setup abnormalities). It is set to 0 '.

For example, as shown in FIG. 5, when the material C generates an event at checkpoint j, the existing dynamic correction amounts for the materials A and B are ΔTDA and ΔTDB, and the equipment constraint margin is αDA and αDB, The dynamic correction amount (ΔTDX) for the tea extract in (Where ΔTdCj is the prediction error of the checkpoint of the material C). Therefore, the above processing is processed for each event occurring simultaneously, and the maximum value is selected to correct the difference extraction time.

And, the correction of the extraction time according to the dynamic correction amount calculated as described above, the sum of the rolling line constraint pitch (PitM) and the dynamic correction amount (ΔTDX), heating furnace for the determined extraction time as shown in Equation 4 below In the direction of increasing by the largest value among the constraint pitch (PitF) and the table pitch (Pitmin). Here, the dynamic correction amount ΔTDX always has a positive value, and always checks the upper and lower limits, and does not perform the dynamic correction when the upper and lower limits are applied.

In addition, in the transfer time between the return check points of the materials on the rolling line, the prediction transfer schedule and the performance transfer schedule are prepared, and then the two are compared to predict the transfer time between the performance transfer time and the prediction transfer time. The learning coefficient is calculated to correct the return schedule calculation (S42).

The learning coefficient is used to reduce the error between the performance transfer and the prediction transfer, and is determined using the learning control of the automatic extraction control. The learning coefficient is determined by receiving performance values and predicted transport time for each region of the rolling line, detecting an error, and comparing the error with an upper limit error (existing for each learning section). It is adopted as the next value and the instantaneous value of the learning coefficient is calculated when it is within the upper limit of the error. Then, it is checked whether the calculated learning coefficient deviates from the upper and lower limits, and if it is out, the previous learning coefficient is adopted as the next learning coefficient, and if it does not deviate, the next learning coefficient is determined from the instantaneous value. The learning section is set for each rough rolling and finishing rolling region in the rolling line.

More specifically, the whole rolling line from the heating furnace 11 to the winding machine 17 is divided into a plurality of zones, and the performance return time and the predicted return time for each zone are calculated. Calculate

Here, TIMEA _i is the time of occurrence of the i-th event in the zone, and TIMEP _i is the predicted return schedule time of the i-th event in the zone.

And, the error between the calculated performance return time and the predicted return time ( ) Is determined to be greater than or less than the error threshold LIMIT _i (which is present in each learning zone, which is a value used as a criterion for calculating the learning coefficient net value), and the determination result is greater than or equal to the threshold LIMIT _i . In this case, the previous value is adopted as the next value, and if the error is within the threshold LIMIT _i , the ratio of the time required to return the performance to the expected return time ( ) Is calculated as the learning coefficient net instantaneous value (CLI _i ) of the corresponding area (i), and then compared with the learning coefficient upper limit value (CLU _i ) and the learning coefficient lower limit value (CLD _i ), and the calculated learning coefficient net instantaneous value (CLI _i). ) Is greater than or equal to the learning coefficient upper limit (CLU _i ) or less than or equal to the learning coefficient lower limit (CLD _i ), (Where ALRN _i is the learning mean constant in zone i and CLO _i is the previous learning coefficient), the next learning coefficient CLN _i is calculated.

In the above, the zone for determining the learning coefficient is, in the case of rough rolling, for example, extraction completion section from the start of extraction of the furnace, material detection section of the extraction stage of the furnace from extraction completion, material detection to sizing press On zone, off section of sizing press, off section of sizing press, on section of first rough mill, from off section of first rough mill, and off section of first rough mill It is divided into eight zones, from the on of the second roughing mill to the on-off of the second roughing mill, to the off of the second roughing mill, and in the case of the finishing rolling process, from the extraction of the roughing press to the input to the first finishing mill. In this case, the first finishing mill can be divided into a total of three zones, from the on-off of the first finishing mill to the winding machine.

The automatic extraction control method as described above is applied together with the timer mode and the manual mode which are the existing extraction operation modes, and is selectively used by the driver's selection.

According to the above, the present invention can firstly maintain the consistency of control by automatically determining the material extraction pitch of the furnace every time the material is extracted, and secondly refer to the results of the combustion control when determining the extraction pitch. By doing so, it is possible to sufficiently satisfy the heating conditions of the furnace, and as a result, it is possible to ensure the material quality for operating in the rolling line. Third, by reflecting the constraints caused by the equipment of the rolling line in the extraction pitch calculation of the tea extract, it is possible to prevent the production shortage due to rejection or extraction delay due to over-extraction.

1 is a block diagram schematically showing a rolling line to which the present invention is applied.

2 is a diagram illustrating the installation of a facility and a material detection sensor (HMD) of a general hot rolling process.

3 is a flowchart showing the overall control flow of the automatic extraction control method of the heating furnace according to the present invention.

4 is a flowchart showing a data processing procedure in detail in the automatic extraction control method of the present invention.

5 is a schematic diagram for explaining an example of a dynamic correction process in the automatic extraction control method of the present invention.

6 is a conveyance pattern diagram of a heating furnace exit table when the sizing press is not used.

7 is a conveyance pattern diagram of a heating furnace extraction table in the case of using a sizing press.

8 is a conveyance pattern diagram at the sizing press entrance side.

9 is a conveyance pattern diagram in a sizing press area.

10 is a pattern diagram for explaining a conveying time in a sizing press.

11 is a transport pattern diagram in the rough rolling zone.

12 is a conveyance pattern diagram in a delay table.

13 is a transport pattern diagram in the finishing rolling zone.

14 is a conveyance pattern diagram in a winding area.

Claims (5)

In the heating furnace automatic extraction control method provided in the heating furnace, sizing press, rough mill, finishing mill, down coil in order Checking completion of extraction of the material in the furnace; As a result of the check, when the extraction of one material is completed, reading operation data including information on the corresponding material and operation and finishing rolling setup data from the hot rolling facility; Creating a predicted transport schedule by predicting a transport schedule from the extraction of the furnace to the completion of the winding through a transport scheduler based on the read operation data; Calculating a minimum extraction pitch between the two extractors from the predicted transport schedule to satisfy the constraint on the rolling line; Determining an extraction time of the tea extract from the calculated minimum extraction pitch and heating constraints transferred from the heating furnace; Collecting a return record for the material extracted in the checking step to create a return return schedule; Detecting completion of a prediction return schedule when the preparation of the performance return schedule is completed; Correcting the difference extraction time of the tea extract material by the detected error and applying the same to a heating furnace; And Training the prediction carrier scheduler to correct the detected error; Automatic extraction control method of the heating furnace characterized in that it is carried out repeatedly. The method of claim 1, wherein the step of reading operation data is Setting duplicate numbers after merits and duplicate numbers after control system abnormalities; Reading setup data of the rough rolling and finishing mill; Converting a unit and a type of the read setup data into a predetermined form; Converting the thermal coefficients of the read setup data into a predetermined unit; Determining a winder to which the extract material is to be wound; And Setting a plurality of fixed values of the hot rolling equipment. The method of claim 1, wherein the determining of the extraction time of the tea extract material The extraction time of the tea extract is determined by extracting the minimum extraction pitch due to the constraint of the rolling line, the minimum extraction pitch due to the constraint in the heating furnace, and the maximum value of the predetermined threshold value to the extraction time performance value of the preceding material. Automatic extraction control method of a heating furnace made of. The method of claim 1, wherein the step of correcting the extraction time of the tea extract material, and applying to the heating furnace (Where k is the tea extract located upstream of steel sheet i, Is the dynamic correction amount of steel plate k, which is the tea extract, αDk is the equipment constraint margin of steel plate k, Is the forecast error of the checkpoint, which is the performance time minus the forecast time.) Calculating a dynamic correction amount, And a step of modifying the extraction time of the determined tea extract in the direction of increasing the rolling line constraint pitch, the dynamic correction amount, the heating furnace constraint pitch, and the table pitch by the largest value. Automatic extraction control method. The method of claim 1, wherein the learning step After dividing the rolling process into several zones, Calculating an error between the performance return time and the prediction return time; Comparing the calculated error with an error threshold value and employing the previous value as the current value when it is out of the error threshold value, and calculating the learning coefficient instantaneous value as a ratio between the performance return time and the predicted return time when the error threshold value is within the error threshold value; , When the set learning coefficient instantaneous value is greater than the upper limit value or the lower limit value compared with the predetermined learning coefficient upper / lower limit value, the previous learning coefficient is adopted to be within the upper / lower limit value range. Where ALRN _i is the learning mean constant in zone _i , CLO _i is the previous learning coefficient, and CLN _i is the learning coefficient. Automatic extraction control method in a heating furnace, characterized in that.