JPH0929315A - Tandem mill control method and controller therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct accurate rolling over the entire length of a succeeding material by reflecting the error of gage meter thickness at least at the tip and tail end of the preceding material on the setting of the screw-down location of the succeeding material. SOLUTION: At the timing when a point A reaches the position of the thickness meter FDH on the outlet side of a tandem mill, the gage meter thickness hgi AT and mass flow thickness hmi AB at each stand are calculated. As a result, a gage meter error ΔSi AT at each stand to the point A is determined. Next, at the timing when the point B reaches the position of the thickness meter FDH, the gage meter thickness hgi AT and mass flow thickness hmi AB at each stand are calculated. As a result, the gage meter error ΔSAV at each stand to the point B is determined. When the point A of the target position in the tip part of the succeeding material reaches the specified timing on the inlet side of the tandem mill, roll gap or the like is calculated with a calculating device FSU for setting and set to a slave direct digital control(DDC) controller. At this time, correction by the gage meter errors ΔSi AT, ΔSi AB at the point A and point B of the succeeding material is added.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tandem mill control method and a control device for determining the set value of the rolling position of each stand by setting calculation when hot rolling steel and non-ferrous materials by the tandem mill.

[0002]

2. Description of the Related Art In a tandem mill for hot rolling,
The plate thickness accuracy of the product is calculated by the process calculator (FSUC: Finisher Set Up Calculation).
) Material temperature and rolling load prediction accuracy and lower DDC
Controller (Digital Dynamic Controlller and below,
Automatic plate thickness control (Abbreviated as PCS) (A
It is governed by the control accuracy of GC: Automatic Gage Control. As is well known, these two types of functions are complementary to each other, and good plate thickness accuracy of the product can be achieved over the entire length in the longitudinal direction of the product coil only when the two functions properly.

In the finish setting calculation, various predictive calculations have been conventionally performed mainly for setting the rolling position and the rolling speed (roll speed) at the time of biting into the tandem mill in the PCS. This is to set the target position on the transfer bar at the position where the actual temperature measurement value on the rough mill exit side or the finishing mill entrance side is aimed, and based on that temperature and the estimated elapsed time, the material to be rolled in the finishing tandem mill is set. This is because the procedure has been adopted in which the temperature is calculated, the rolling load is predicted based on the temperature, and the rolling position and roll speed are determined. Normally, the target position of the bar tip is about 1 to 2 m from the tip of the bar. This is due to the effect of descaling spray on the rough mill at the leading edge of the bar and the turn up / down movement of the rough mill.
This is because the influence of (p / down) becomes a disturbance for temperature measurement, and the temperature on the outlet side of the rough mill may not be measured accurately.

In the conventional finish setting calculation, the aiming position is determined in advance at the tip of the bar in this way, and the predictive calculation for the aiming point is the center. Further, on the delivery side of the rolling mill after rolling. The learning calculation based on the actual measurement data was also performed for the same point. Setting the target point in the vicinity of the tip of the transfer bar in this way is important from the perspective of placing importance on the biteability of the transfer bar into the finishing mill and completing the setting of the finishing mill at the earliest possible timing. It was a simple method.

[0005]

As in the conventional finish setting calculation, the method of setting the target point near the tip of the transfer bar and using the data at that point has the following drawbacks. In other words, if the tip data is data that can represent a considerable part of the total length of the coil, no problem will occur, but for example, when the rolling speed of the finishing mill (speed of the Vivot stand) is changed after biting. is there. At this time, the load prediction based on the temperature of the target point and the transfer bar thickness of the target point in the finish setting calculation of the tip portion cannot represent the data of the subsequent portion of the rolled material following the target point. Normally, this change is tracked by using AGC or other dynamic control, and the target coil thickness and width of the product coil are controlled so as to hit the target. The data tracked at that time are basically the actual values of rolling load, actual values, actual values of the rolling position, etc.The output of dynamic control based on these values is the amount of deviation from the calculation result of the finish setting calculation. Treated

At this time, the temperature of the rolled material and the deformation resistance, which is the physical deformation strength of the rolled material, are not calculated, but the already calculated tip data is used as a reference. Therefore, from the viewpoint that the control amount of the dynamic control is the control amount for the reference data of the tip, it is necessary to always set a limit to prevent troubles due to an excessive amount of deviation of the rolling position, for example. There is. In this way, each control amount is a deviation amount, so it is limited by the limit, and since the reference value of the deviation amount is a predicted measurement value based on the target position of the tip of the transfer bar, it is determined over the entire length of the coil. In some cases, it may be difficult to control the target value of (for example, target plate thickness) and keep the target. This is because it is impossible to calculate at a pitch like a DDC controller, or it is not realistic to execute it, considering the content and amount of prediction calculation performed by a process computer. This is because there are problems. Therefore, even if the prediction calculation accuracy of the finish setting calculation at the target position of the transfer bar tip is good, it is not always possible to achieve good product accuracy in the subsequent parts, and for this reason, the quality of the product coil itself ( There was a problem that the plate thickness, plate width, temperature, etc.) became insufficient.

The present invention has been made in order to solve the above-mentioned problems, and is a preceding rolled material (hereinafter also referred to as a preceding material).
By reflecting the error of the gauge meter plate thickness at least at the tip and tail ends of the rolled material (hereinafter, also referred to as the following material) in the rolling position of the following material, the accuracy is improved over the entire length of the following material. An object of the present invention is to provide a control method and a control device for a tandem mill that can realize good rolling.

[0008]

According to the present invention, the leading end and the tail end of the preceding material to be bitten in the tandem mill are set as the target positions, respectively, and on the product strip on the exit side of the final stand corresponding to these target positions. While detecting the temperature of the position, plate thickness and plate width, detects the rolling load and the rolling position at the detection timing, while calculating the gauge meter plate thickness in each stand based on these detected values,
Based on the calculated gauge meter plate thickness and the model coefficient of the setting calculation, the advanced value actual value of each stand and the mass flow plate thickness of each stand are calculated, and then the difference between these two plate thicknesses is calculated, Based on the actual value and plate thickness difference of each stand with respect to the target point of the tip, and the actual value and plate difference of each stand with respect to the target point of the tail end Since the set value of the rolling position of each stand of the material is corrected, accurate rolling can be realized over the entire length of the following material.

In another invention, not only the front end and the tail end but also the longitudinal middle portion is set as the target position with respect to the preceding material, and the advanced ratio actual value of each stand corresponding to a total of three target positions and Since the set value of the rolling position of each stand of the following material is corrected based on the plate thickness difference, the plate thickness accuracy over the entire length of the following material can be further improved.

Another aspect of the invention is that, based on the set value of the roll gap of each stand corresponding to the target position of the rolled material, the roll gap of each stand at the position corresponding to each rolled material position between the target positions is determined. Since the reference value is sequentially corrected by linear interpolation, it is possible to prevent a reduction in plate thickness accuracy due to changes in roll conditions such as roll friction and thermal crown.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments. FIG. 1 is a block diagram showing a first embodiment of the present invention. As shown in the figure, the tandem mills F _{1 to} F _N (the number of stands:
A temperature measuring device FDT, a plate thickness meter FDH, and a plate width meter FDW are installed on the output side of N). Respectively rolling load measuring device L ₁ ~L _N in tandem mill F ₁ to F _N, the pressing position detector SD ₁ to SD _N, roll speed detector RV ₁ ~RV _N
Are provided.

Then, the position on the product strip at the exit side of the F _N stand, which corresponds to the target position A of the finish setting calculation of the tip end of the rolled material, is obtained when passing the installation position of the temperature measuring instrument FDT. A temperature output T _FD ^AT and a plate thickness output h _F ^AT obtained when passing through the installation position of the plate thickness gauge FDH,
The strip width output _BF ^AT obtained when passing the installation position of the strip width gauge FWD and the rolling that is sampled at the timing when the position on the product strip corresponding to point A passes through the installation position of the strip thickness gauge FDH. Actual load values P _i ^{AT of the} load measuring devices L _{1 to} L _N (i = 1 to N: the same applies hereinafter)
And the reduction position actual values S of the reduction position detectors SD _{1 to} SD _N
i ^AT and roll speed detector RV ₁ based on the roll speed actual value V _i ^AT of ～RV _N, gauge meter thickness h _gi ^AT gauge meter thickness computing unit GM _i provided for each stand at each stand Ask for.

Further, the thickness output h of the thickness gauge FDH
And _F ^AT, and the roll speed actual value V _i ^AT the roll speed detector RV ₁ ~RV _N, based on the model coefficients output a _j of setting calculation device FSU, the procedure of the mass flow plate thickness arithmetic unit MF _i convergence calculation Is used to obtain the advanced rate actual value f _i ^AT of each stand and the mass flow plate thickness h _mi ^AT of each stand. Subtractor W
_i is the mass flow plate thickness h _mi ^AT obtained by the mass flow plate thickness calculator MF _i and the gauge meter plate thickness calculator GM _i
The plate thickness difference from the gauge meter plate thickness h _gi ^AT , that is, the gauge meter error ΔS _i ^AT is calculated and sent to the setting calculation unit FSU.

The above-mentioned gauge meter plate thickness calculator GM _i ,
The mass flow plate thickness h _mi ^AT and the subtractor W _i perform the following calculation at different timings. That is, the gauge meter plate thickness calculator GM _i is obtained when the position on the product strip corresponding to the target position B of the finish setting calculation of the tail end of the rolled material passes through the installation position of the temperature measuring device FDT. Temperature output T
_FD ^AB , the thickness output h _F ^AB obtained when passing the installation position of the thickness gauge FDH, the width output B _F ^AB obtained when passing the installation position of the width gauge FDW, and the point B In the timing at which the position on the product strip corresponding to the above passes the installation position of the plate thickness gauge FDH, the actual load values P _i ^AB by the rolling load measuring devices L _{1 to} L _N and the rolling position detector SD ₁ to and SD _N simmer pressing position actual value S _i ^AB, based on the roll speed actual value V _i ^AB by the roll rate detector RV ₁ ~RV _N, determine the gauge meter thickness h _gi ^AB in each stand.

The mass flow plate thickness calculator MF _i is a plate thickness gauge F
DH plate thickness output h _F ^AB , roll speed detectors RV _{1 to} RV
_{Based on the} actual roll speed value V _i ^{AB of} _N and the model coefficient output a _j of the setting calculation device FSU, the advanced rate actual value f _i ^AB of each stand and the mass flow plate thickness h of each stand are used by the procedure of the convergence calculation. _{Ask for mi} ^AB . The subtractor W _i finds the difference (gauge meter error) ΔS _i ^AB between the gauge meter plate thickness h _gi ^AB and the mass flow plate thickness h _mi ^AB , and sends this to the setting calculation unit FSU.

The setting calculation device FSU has the above-mentioned target position A.
The gauge meter error ΔS _i ^AT for the point and the gauge meter error ΔS _i ^AB for the target position B point are received to calculate the setting of the trailing material. The stand down position S _i ,
A reduction position setting value S _i ^SET with a weight ω ₁ added to the originally calculated S _i ^CAL is calculated, and the reduction setting device F
It is configured to output to S _i .

Hereinafter, the operation of the present embodiment will be described. First, the setting calculation device FSU sets the target values of the rolling position and speed for rolling the trailing material based on the actual temperature and the actual plate thickness of the transfer bar on the tandem mill entrance side, and outputs the target values of the finishing mill, which is the target specification of the product. It has a function to set the lower DDC controller so that the side plate thickness and temperature can be achieved. At this time, basically, in order to stabilize the rolling state when the front end of the transfer bar is bitten into the tandem mill, the setting calculation device FSU is set to the target position A point at the tip of the transfer bar. Predict and calculate the quantities.

At this time, one of the main functions is to obtain the rolling position set value S _i ^SET of each stand by a gauge meter calculation. However, in the gauge meter calculation, unavoidable errors occur every moment. That is, the surface temperature of the roll may be increased due to the fact that the roll wears during rolling of one rolled material, or the rolled material keeps in contact with a rolled material having a temperature higher than 800 ° C. from the tip to the tail end. Rises and thermally expands, so that a so-called thermal crown is given, and a gauge meter error inevitably occurs. Moreover, it is 1
It is practically impossible to trace the entire length of the rolled material of the book.

Therefore, as in the conventional control device, the calculation of the gauge meter error with respect to the target position A at the tip of the transfer bar and the correction calculation based on the gauge meter error in the rolling position calculation of the trailing material based on the calculation are used. According to the idea, after the rolling of the rolled material by the tandem mill is started, the gauge meter error caused by the change of the roll condition after the calculation of the gauge meter error at the tip end aiming position A point is completely suppressed. Will not be considered in the gauge meter calculation. It is clear that this is one of the causes of the instability over the entire length of the rolled material and the error in the calculation of the rolling position with respect to the tip in the rolling of the trailing material, and this error is absorbed by some method. It will be necessary to attempt this.

Further, as a fact that there is no problem in the case of equipment in which the speed at the time of biting and the speed at the stationary portion hardly change, it is necessary to properly consider the speed in the calculation of the gauge meter. For grasping the error of the gauge meter calculation when accelerating the steady part, for example, it is not possible to consider the speed factor in the conventional control device that performs the gauge meter calculation only for the target position A point. is there.

In order to solve such a problem, basically, a tail end target position B point for setting calculation is newly provided, and the same calculation as that of the tip end target position A point is performed for that point. It is possible to deal with the error of both gauge meters thus obtained by some means by appropriately reflecting it in the calculation of the rolling position in the setting calculation of the following material. At this time, for example, the gauge meter error ΔS _i obtained at the target position A of the tip end portion
^In order to properly consider both the ^AT and the gauge meter error ΔS _i ^AB obtained at the target position B at the tail end in the calculation of the rolling position of the trailing material, there are the following methods. That is, the weight ω _i is introduced like ΔS _i = ω _i · ΔS _i ^AT + (1−ω _j ) · ΔS _i ^AB (1) to calculate two values for the rolling position calculation of the trailing material. The degree of reflection of the gauge meter error should be adjusted.

The contents of each calculation will be further described below using standard mathematical expressions. The gauge meter arithmetic expression is expressed by the following function, for example. This calculation formula is common for the contents in each stand, it referred to omit the suffix i of F _i. h = S _o + S _m (2) Here, h is the gauge meter plate thickness at the exit side of the F _i stand (m
m) and S _o are the true roll gap (mm: difference between the rolling positions of the upper and lower work rolls in the central portion in the plate width direction) and the mill elongation (mm) during S _m rolling.

Further, the reduction position S _i ^SET is, for example,
It can be calculated as follows. ^{_{S i SET = S z + S}} o + S OIL + S a -S RW + S RH + S Z SET + △ S i (3) S z = S mo -S OIL0 (4) where, S _i ^SET: F _i stand pressure position Set value (m
m) S _z : Roll gap during zero adjustment (mm) S _OIL : Oil film thickness during rolling (mm) S _a : Gap displacement due to roll bending force (mm) S _RW : Roll wear amount (mm) S _RH : Roll Thermal crown amount (mm) S _Z ^SET : Indicator setting value during zero adjustment (mm) ΔS _i : Gauge meter error correction amount (mm) S _z : Roll gap during zero adjustment (mm) S _mo : During zero adjustment Mill elongation (mm) S _OIL0 : Oil film thickness (mm) during zero adjustment. Among the above variables, for example, the oil film thickness S _OIL during rolling is expressed as a function of speed, and the roll wear amount S _RW
Is the amount that changes momentarily during rolling of one rolled material.

On the other hand, the calculation of the gauge meter plate thickness is performed as follows at the target position A point. h _g ^AT = S _o ^AT + S _m ^AT (5) where h _g ^AT is the actual gauge meter plate thickness value (mm) at the target position A point, S _o ^AT is the true roll gap (mm) at the point A, Similarly, S _m ^AT is the actual value (mm) of the mill elongation at point A. All the quantities for calculating these are based on the actual collected values for point A.
Exactly the same is as shown below at the target position B.

H _g ^AB = S _o ^AB + S _m ^AB (6) Here, h _g ^AB is the actual gauge meter plate thickness value (mm) at the target position B point, and S _o ^AB is the true roll gap at point B ( mm) and S _m ^AB are the actual values (mm) of the mill elongation at point B as well. All the quantities for calculating these are also based on the actual result collection value for the point B.

The mass flow plate thickness is calculated for point A as follows.

[0027]

[Equation 1] Similarly, for point B, the following is performed.

[0028]

[Equation 2] Where: h _mi ^AT : F _i stand mass flow plate thickness (point A: m
m) h _mi ^AB : F _i stand mass flow plate thickness (point B: m
m) h _N ^AT : F _N stand exit side plate thickness measured by FDH (A point: mm) V _N ^AT : F _N stand roll peripheral speed actually measured value (A point: m
pm) V _i ^AT: F _i stand roll peripheral speed measured value (A point: m
pm) f _N ^AT : F _N stand advanced rate actual value (A point: −) f _i ^AT : F _i stand advanced rate actual value (A point: −) h _N ^AB : F _N stand outgoing side plate thickness measured by FDH (Point B: mm) V _N ^AB : F _N Stand roll peripheral speed measured value (Point B: m
pm) V _i ^AB: F _i stand roll peripheral speed measured value (B point: m
pm) f _N ^AB: F _N stand advanced rate actual value (B point :-) f _i ^AB: an F _i stand advanced rate actual value (B point :-).

Since the advance rate is a function of the mass flow plate thickness,
Equations (7) and (8) require a procedure for determining the mass flow plate thickness by convergence calculation. As can be seen from the contents of the formula, the mass flow plate thickness is calculated based on the actual measured value of the plate thickness on the tandem mill outlet side, and the most accurate value of the plate thickness on the outlet side of each stand is given except for the error of the advanced rate model. Is. Now, the relationship between the plate thickness and the gauge meter error at the tip end target position A point and the tail end target position B point will be described with reference to FIG. Now, the preceding material M1 and the succeeding material M2 continuous with it
think of. For the preceding material M1, there are a tip end target position A point and a tail end target position B point. When the point A reaches the position of the plate thickness gauge FDH on the tandem mill exit side, the gauge meter plate thickness h _gi ^AT and the mass flow plate thickness h _mi ^AT of each stand with respect to the point A are calculated. Based on this, the gauge meter error ΔS _i ^AT of each stand with respect to the point A is obtained.

Next, the gauge meter plate thickness h _gi ^AB and the mass flow plate thickness h _mi ^AB of each stand with respect to the point B are calculated at the timing when the point B reaches the position of the width meter FDH. Based on this, the gauge meter error of each stand for point A △
Find S _i ^AB . In order to roll the following material M2, the preceding material M
The target position A of the tip of the trailing material M2 defined by the same definition as 1
When the point reaches a specific timing on the tandem mill entrance side, the setting calculator FSU calculates the roll gap and the like for the trailing material M2 and sets it in the lower DDC controller. At this time, in the calculation of the roll gap, corrections are made by gauge meter errors ΔS _i ^AT and ΔS _i ^AB at both points A and B of the preceding material. The correction method is, for example, using an arithmetic expression as shown in Expression (1),
A method of apportioning can be considered.

As a result, the set value of the rolling position in the rolling of the trailing material is calculated in consideration of the gauge meter error at both points A and B of the leading material, and therefore, the plate thickness accuracy of the trailing material is the total length. The effect that it is improved over the preceding material can be obtained. In the conventional control device, the roll gap of the trailing material is calculated based on the gauge meter error at the point A of the leading material, while the length of the leading material changes moment by moment. It can be said that this is possible because the gauge meter error is taken into consideration in the form of calculation of the gauge meter error at the target position B point at the tail end.

Further, it is rational to consider a lot of data of the target position B at the tail end of the gauge meter error in the roll gap calculation of the trailing material. That is, most of the content of the gauge meter error is considered to be the wear of the roll or the change of the roll diameter itself due to the thermal crown. Therefore, at least the wear of the roll is over the entire length of rolling of one coil. Since this is the amount of the property that progresses, the gauge meter error at the target position B point of the tail end of the preceding material is closer to the state of the roll when calculating the roll gap of the leading end of the following material. Can be said. Thus, according to the first embodiment shown in FIG. 1, it is possible to realize accurate rolling over the entire length of the following material.

FIG. 3 is a block diagram showing a second embodiment of the present invention. This is a case where, in addition to the target position B point at the tail end, the target position C point is further provided at the center of the entire coil length. That is, the feature of this embodiment is that when the speed greatly changes during rolling of one rolled material, the target position C point is further provided in the central portion in accordance with the speed change pattern. It is considered that the accuracy of the plate thickness over the entire length of the trailing material is improved by using it for the roll gap calculation of the trailing material in consideration of the gauge meter error in.

At this time, the method of correcting the roll gap calculation of the trailing material may similarly be obtained by adding weights. For example, the following formula is used. ΔS _i = (1-ψ ₁ ) · ΔS _i ^AT + ψ _i · ω _i · ΔS _i ^AM + (1-ω _i ) · ΔS _i ^AB (9) where ΔS _i ^AM is the center of the entire length. The gauge meter errors ψ _i and ω _{i at} the target position C point of the section are weights for the gauge meter error at the tip A point and the tail end B point, respectively. According to this embodiment, even if the speed for one rolled material changes every moment during rolling, the gauge meter error of the preceding material is effectively evaluated for rolling of the entire length of the coil. As in the embodiment of FIG. 1, in the rolling of the following material, the plate thickness accuracy is improved over the entire length of the coil.

FIG. 4 is a block diagram showing a third embodiment of the present invention. This is a gauge meter error Δ calculated based on each of the target position A point at the tip end and the target position B point at the tail end obtained in the rolling of the preceding material.
Using S _i ^AT and ΔS _i ^AB , the roll gap set value S _i ^TSET at the target position at the leading end and the roll gap set value S _i ^BSET at the target position at the tail end are separately provided in rolling of the trailing material. , Calculated in consideration of the gauge meter error of the preceding material. Then, the lower DDC controller, as shown in FIG.
The gap setting value during rolling of the trailing material is linearly interpolated, and the roll gap reference is changed every moment. This allows
Similar to the above example, in the rolling of the succeeding material, it is possible to obtain a product coil with good plate thickness accuracy over the entire length. In other words, the roll gap standard changes over the entire length of one rolled material, which causes changes in speed and temperature, as well as changes in roll conditions such as roll wear and thermal crown, to set the gap. The value itself is ticking
Since these state changes are tracked, even if the rolling condition is far from the biting state during rolling,
It is possible to solve the problem that the plate thickness is not obtained with sufficient accuracy because it violates the limit.

[0036]

As described above, according to the present invention,
It is possible to reflect the gauge meter error at both the target position of the front end of the rolled material and the target position of the tail end in the setting of the reduction position for rolling the subsequent material. Rolling of the product coil with good accuracy such as plate thickness, plate width, and temperature can be realized over the entire length of the coil from the end to the tail end. As described above, according to the present invention, it is possible to grasp the gauge meter error over the entire length of the rolled material with respect to a plurality of representative points, and reflect it in the succeeding material rolled subsequently. The setting of the roll gap can be realized. Therefore, in the rolling of the trailing material, the conventional control device sometimes conflicts with the movement limit of the gap, so that good plate thickness accuracy cannot be partially obtained, or the quality of the product coil itself becomes insufficient. This has the effect of avoiding the problem.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment of the present invention.

FIG. 2 is an explanatory view of the principle that the calculation of gauge meter errors at a plurality of target positions effectively acts on rolling of the following material in order to explain the operation of the present invention.

FIG. 3 is a block diagram showing a configuration of a form of a second exemplary embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration according to a third embodiment of the present invention.

FIG. 5 is a diagram showing a relationship between a roll gap set value of a rolled material and a rolling position in order to explain the operation of the third embodiment of the present invention.

[Explanation of symbols]

F _i tandem i-th stand F _N tandem mill final stand FDT temperature measuring instrument FDH thickness gauge FDW plate width meter L _i i-th stand rolling load measuring device SD _i i-th stand rolling position detector RV _i i-th stand of the mill Roll speed detector GM _{i i-} th stand gauge meter plate thickness calculator FSU setting calculator MF _i i-th stand mass flow plate thickness calculator W _i subtractor FS _i i-th stand roll-down position setter M1 Leading rolled material (leading material ) M2 Rolled material (rear material)

Claims (6)

[Claims] 1. A method for controlling a tandem mill in which a set value of a rolling position of each stand is determined by setting calculation when hot rolling a rolled material by a tandem mill. And the strip width and the rolling load and the rolling position of each of the stands, respectively, and the temperature at the position on the product strip corresponding to the target position on the rolled material, the detection value of the strip thickness and the strip width, and the detection thereof. Based on the detected value of the rolling load and the rolling position at the timing, calculate the gauge meter plate thickness in each stand, based on the calculated gauge meter plate thickness and the model coefficient of the setting calculation, the advanced rate of each stand The actual value and the mass flow plate thickness of each stand are calculated, and the difference between the calculated gauge gauge plate thickness and the calculated mass flow plate thickness is obtained. In addition, the set value of the rolling position of each stand is obtained for each rolled material by setting calculation, and each stand is calculated with respect to the target position of the leading end portion and the tail position of the preceding rolled material. The method for controlling a tandem mill, which comprises correcting the set value of the rolling position for the rolled material in the subsequent step based on the actual value of the advanced rate and the difference in strip thickness. 2. A method of controlling a tandem mill in which a set value of a rolling position of each stand is determined by setting calculation when hot rolling a rolled material by a tandem mill. And the strip width and the rolling load and the rolling position of each of the stands, respectively, and the temperature at the position on the product strip corresponding to the target position on the rolled material, the detection value of the strip thickness and the strip width, and the detection thereof. Based on the detected value of the rolling load and the rolling position at the timing, calculate the gauge meter plate thickness in each stand, based on the calculated gauge meter plate thickness and the model coefficient of the setting calculation, the advanced rate of each stand The actual value and the mass flow plate thickness of each stand are calculated, and the difference between the calculated gauge gauge plate thickness and the calculated mass flow plate thickness is obtained. , The setting value of the rolling position of each of the stands for each rolled material by setting calculation, for the target position of the leading end portion of the preceding rolled material, the target position of the rolling direction central portion and the target position of the tail end portion A method of controlling a tandem mill, characterized in that the set value of the rolling position of the succeeding rolled material is corrected based on the advanced rate actual value and the plate thickness difference of each stand calculated respectively. 3. A roll gap reference value of each stand at a position corresponding to each rolling material position between the aiming positions is linearly interpolated based on set values of the roll gaps of each stand with respect to the plurality of aiming positions of the rolled material. The tandem mill control method according to claim 1 or 2, wherein the tandem mill control is performed sequentially by 4. A tandem mill control device for hot rolling a rolled material by a tandem mill, wherein the set value of the rolling position of each stand is determined by setting calculation. And detecting means for detecting the strip width and the rolling load and the rolling position of each of the stands, and the temperature of the product strip position corresponding to the target position on the rolled material, the strip thickness, and the strip width and the respective detected values thereof. Based on the detected values of the rolling load and the rolling position at the detection timing, a gauge meter plate thickness calculator for calculating the gauge meter plate thickness in each stand, and a model coefficient for the calculated gauge meter plate thickness and setting calculation. Based on the actual value of the advanced rate of each stand and the mass flow plate thickness of each stand, A subtractor for obtaining the difference between the gauge meter plate thickness and the calculated mass flow plate thickness, and for obtaining the set value of the rolling position of each stand for each rolled material by setting calculation, and the leading end of the preceding rolled material. Setting calculation for correcting the set value of the rolling position for the following rolled material based on the actual value of the advanced ratio and the plate thickness difference of each stand calculated for the target position of the And a device for controlling a tandem mill. 5. A tandem mill control device for determining a set value of a rolling position of a plurality of stands arranged in a tandem by setting calculation when hot rolling a rolled material, and a temperature of a product strip at a delivery side of a final stand. ,
Detecting means for detecting the plate thickness and plate width and the rolling load and the rolling position of each of the stands, and the detected value of the product strip position corresponding to the target position on the rolled material, the plate thickness and the plate width And a gauge meter plate thickness calculator for calculating the gauge meter plate thickness in each stand based on the rolling load and each detected value of the rolling position at the detection timing, and a model of the calculated gauge meter plate thickness and setting calculation Based on the coefficient, a mass flow plate thickness calculator for calculating the advanced rate actual value of each stand and the mass flow plate thickness of each stand, and the difference between the calculated gauge meter plate thickness and the calculated mass flow plate thickness are obtained. A subtracter and setting calculation of the rolling position of each stand for each rolled material by setting calculation, and the target position of the leading end of the preceding rolled material and rolling direction Correct the set value of the rolling-down position for the following rolled material based on the actual value of the advanced rate and the plate thickness difference of each stand calculated for the target position of the central part and the target position of the tail end part, respectively. A tandem mill control device comprising a setting calculation device. 6. A roll of each stand at a position corresponding to each rolling material position between aiming positions, based on a set value of a roll gap of each stand for a plurality of aiming positions of the rolled material output from the setting calculation device. 6. The gap reference value is sequentially corrected by linear interpolation.
The tandem mill control device described in 1.