JP5239728B2 - Rolling method and rolling apparatus for metal sheet - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a rolling method and rolling apparatus for a metal plate, and in particular, a rolling method for a metal plate that can produce a metal plate with no meandering and camber or extremely lightly meandering and camber more stably than before. And a rolling device.

  One of the important issues in the rolling operation of a metal plate material is to make the elongation rate of the rolled material equal between the working side and the driving side. In the following description, the working side and the driving side are referred to as left and right for the sake of simplicity. If the difference in elongation becomes uneven on the left and right, not only the flat shape and dimensional accuracy of the rolled material such as the camber and the plate thickness wedge will be caused, but also a plate trouble such as meandering and squeezing may occur.

  As an operation means for equalizing the left and right elongation, elimination of the left-right asymmetric component at the rolling position of the rolling mill, that is, a rolling leveling operation is used. Normally, the rolling leveling operation is mostly performed by the operator while carefully observing the rolling operation for both the setting before rolling and the operation during rolling. It cannot be said that the board trouble is sufficiently controlled.

  In order to solve the above-described problem, Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique for performing the reduction leveling control based on the ratio of the load cell load of the rolling mill to the sum of the left and right differences.

  Patent Document 2 below discloses a technique for manipulating the rolling leveling by directly detecting the amount of deviation (hereinafter also referred to as meandering amount or off-center amount) of the rolling material on the rolling mill entry side.

  Further, in Patent Document 3 below, in order to identify the left-right asymmetry of the deformation characteristics of the rolling mill in particular, the kiss roll is tightened by operating the reduction device, and the work side and drive side reduction positions and the rolling load are measured. The load cell output is measured with respect to a plurality of rolling position conditions, and the deformation of the roll system corresponding to each rolling position condition is calculated and separated. A technique for identifying an asymmetry and using the deformation characteristics of the rolling mill thus obtained to implement an optimum reduction leveling setting is disclosed. Here, kiss roll tightening means that the upper and lower work rolls are brought into contact with each other in a state where no rolling material is present, and a load is applied between the rolls. Further, the deformation characteristics of the rolling mill are the deformation characteristics of the rolling mill housing and the reduction system as described above, and generally mean what is called mill stretch.

  Further, in Patent Document 4 below, when extracting the zero point adjustment by tightening the kiss roll and the left-right asymmetry of the deformation characteristics of the rolling mill, each of the thrust reaction force acting on the rolls other than the reinforcing roll and the upper and lower reinforcing rolls A technology that implements optimum reduction leveling setting and control based on the zero point of the reduction device obtained by measuring the reaction force of the reinforcing roll acting on the reduction fulcrum position and separating the disturbance due to the thrust force between the rolls and the deformation characteristics of the rolling mill. It is disclosed. Here, the thrust reaction force is used to hold the roll in place against the resultant force relating to each roll of the thrust force generated mainly by the presence of a minute cross angle between the rolls on the contact surface of each roll body. The reaction force.

  However, the techniques for making the difference between the left and right elongation rates of the rolled material exemplified in Patent Document 1 and Patent Document 2 described above as zero aim to optimize the rolling leveling as the control means, Each of these techniques is a feedback type control technique that causes a difference in the elongation rate of the rolled material and causes an action after it is detected as meandering or camber of the rolled material. In the case of this type of control, there is a significant time delay between the occurrence of a left-right difference in the elongation rate of the rolled material and the detection of this as meandering or camber. And the camber problem has not been fully solved.

  The techniques of Patent Document 3 and Patent Document 4 described above, unlike the feedback technique, accurately grasp the left-right asymmetry of the deformation characteristics of the rolling mill, and further deform the rolling material such as dimensions and deformation resistance. The purpose is to realize the operation that does not generate meandering and camber from the rolling start of the rolling material head by optimizing the rolling setting value before starting rolling after accurately grasping the left-right asymmetry of characteristics I was trying.

  However, when the technique disclosed in Patent Document 3 was performed, depending on the rolling mill, sufficient reproducibility may not be seen in the deformation characteristics of the identified rolling mill housing and the rolling reduction system. The set value of the reduction position cannot always be optimized, and as a result, the occurrence of meandering and camber cannot be sufficiently prevented. This is because the disturbance due to the thrust force between the rolls is included in the left-right difference in the load cell load, and it is considered that there is a possibility that a large error is included in the identification result of the left-right asymmetry of the deformation characteristics of the rolling mill.

  As a technique that can eliminate the influence of the inter-roll thrust force, there is a technique disclosed in Patent Document 4 described above. This technology considers the influence of the thrust force between rolls and extracts the rolling zero adjustment and the left-right asymmetry of the deformation characteristics of the rolling mill. Therefore, the zero point of the rolling mill and the deformation characteristics of the rolling mill can be obtained with good reproducibility. it can. However, in the above technique, it is essential to measure the thrust reaction force acting on rolls other than the reinforcement roll and the reinforcement roll reaction force acting on each fulcrum fulcrum position of the upper and lower reinforcement rolls. There is a problem that it is difficult to apply to a rolling mill that does not have a measuring device capable of measuring.

As a technique that can possibly solve the problems of the above technique, the difference between the working side and the driving side of the rolling direction force acting on the work roll roll chock described in Patent Document 5 (hereinafter referred to as the rolling direction force). A technique of meandering and camber control based on the left-right difference) is disclosed. This technology directly detects the moment acting on the material due to the left / right difference in elongation rate causing meandering and camber as the left / right difference in rolling direction force acting on the work roll chock, and controls the reduction leveling. Measurement and control can be realized without time delay.
Japanese Patent Publication No. 58-51771 JP 59-191510 A Japanese Patent No. 2604528 Japanese Patent No. 3499107 International Publication WO 2004-082860

  The present inventors apply the method of the invention disclosed in Patent Document 5 applicable to a single stand rolling mill to a continuous stand rolling mill such as a cold tandem rolling mill or a hot rolling finish rolling mill. We examined whether it was possible.

  Using a rolling test machine that simulates a continuous stand, slab test material of the same size was rolled for several conditions at the same temperature, the same rolling reduction, and the same rolling speed. It was seen that there was not. That is, it was found that due to some disturbance, the conventional technology cited as Patent Document 5 is difficult to apply to a continuous stand even if it can be applied to a single stand rolling mill.

  Accordingly, the present invention advantageously solves the above-mentioned problems of the prior art relating to meandering and camber control, and can stably produce a light metal plate material having no meandering and camber or extremely meandering and camber. An object of the present invention is to provide a rolling method and rolling apparatus for a metal plate material in a continuous stand.

  The inventors have obtained the following findings as a means for solving the above-mentioned concerns after intensive studies.

  First, using a continuous stand rolling machine, when tension is applied and rolling is performed accurately in the width direction so as not to cause deviation of the material to be rolled at the start of control, even in subsequent rolling, some degree of accuracy is achieved. Serpentine and camber control was possible. However, if the amount of deviation from the center has occurred in the material to be rolled at the start of control, meandering camber control could not be performed well.

  Next, when the rolling was continuously performed so that no tension was applied, the meandering and camber control could be performed as in the prior art even if the deviation from the center occurred.

  As a result of thorough investigation and analysis of the influence of disturbance on the difference in rolling direction force in the above meandering and camber control, that is, the difference in rolling direction force left and right, including these experiments, both the entry side and the exit side of the rolling mill or both On the other hand, when the tension is acting on the material to be rolled, the difference in the rolling direction force left and right that is considered to be caused by other than meandering and camber changes depending on the amount of deviation of the material to be rolled and the moment generated by the action of the tension. Became clear.

  That is, when applied to rolling where tension is acting on both the entry side and the exit side, such as a continuous stand rolling mill, depending on the amount of deviation from the center of the material to be rolled and the action of tension. Moment is generated, and these are disturbances in the rolling direction force left / right difference caused by the left / right difference in elongation that causes meandering and camber. Therefore, it is considered that accurate meandering and camber control could not be performed.

  Therefore, in the case where tension is applied to both or one of the entry side and the exit side of the rolling mill, in addition to the measurement of the difference in the rolling direction force, the deviation amount and tension value of the material to be rolled are Measure on either the entry side or the exit side, or calculate the effect of the moment due to the amount of displacement and tension acting on the material to be rolled from the measured values. It has been found that, by correcting, the influence of the above disturbance can be eliminated, and more accurate meandering and camber control can be performed as compared with the prior art.

The present invention has been made on the basis of the above-mentioned findings, and the gist thereof is the following contents as described in the claims.
(1) In a method for rolling a metal sheet using a rolling machine for a metal sheet having at least a work roll and a reinforcing roll,
Measure the rolling direction force acting on the work side and drive side roll chock of the work roll,
Measure the amount of deviation of the material to be rolled from the center of the rolling mill on either the entry side or the exit side of the rolling mill, or either
Measure the tension of the material to be rolled on the entry side and / or exit side of the rolling mill,
The difference between the working side and the driving side of the rolling direction force (hereinafter referred to as the difference) is calculated, and the difference is corrected by the deviation amount and the tension,
The left-right asymmetric component control amount is calculated so that the corrected difference becomes a control target value that is normally zero ,
A rolling method for a metal plate material, wherein a left-right asymmetric component of a roll opening degree of the rolling mill is controlled based on the control amount.
(2) When correcting the difference between the working side and the driving side of the rolling direction force, a moment is obtained based on the shift amount and the tension, and the difference is corrected based on the moment. The method for rolling a metal sheet according to (1) .
(3) The method for rolling a metal sheet according to (1) or (2) , wherein the work roll is offset to the rolling entry side or the rolling exit side with reference to the reinforcing roll.
(4) The thickness of the work side and the drive side of the material to be rolled is measured on both the entry side and the exit side or the exit side of the rolling mill, and based on the difference between the plate thickness and the corrected rolling direction force. The method for rolling a metal sheet according to any one of (1) to (3) , wherein the control target value is learned.
(5) In a rolling apparatus having a rolling mill of a metal plate material provided with at least a work roll and a reinforcing roll, the detection apparatus measures the rolling direction force acting on the work side and drive side roll chock of the work roll, The load detecting device provided on both or one of the roll chock in the rolling direction and / or the load side, and the amount of deviation of the material to be rolled from the center of the rolling mill on both the inlet and outlet sides of the rolling mill or A displacement detector that measures either one of them,
A tension detection device that measures the tension of the material to be rolled on either or both of the entry side and the exit side of the rolling mill;
An arithmetic device for calculating a difference in rolling direction force between the working side and the driving side acting on the roll chock;
A correction device for correcting the difference based on the shift amount and the tension;
It has a control device that controls the roll opening of the rolling mill based on the calculated value of the left-right asymmetric component control amount of the roll opening so that the corrected difference becomes a control target value that is normally zero. And a metal sheet rolling apparatus.
(6) an arithmetic unit for correcting the difference by calculating the moment on the basis of the shift amount and the tension, characterized in that an arithmetic unit for correcting the difference based on the moment, on the (5) The rolling apparatus of the metal plate material of description.
(7) The rolling device for a metal sheet according to (5) or (6) , wherein the work roll is offset to the rolling entry side or the rolling exit side with respect to the reinforcing roll.
(8) A plate thickness measuring device that measures the thickness of the work side and the drive side of the material to be rolled on both the entry side and the exit side of the rolling mill, or the exit side, and the thickness and the corrected rolling direction force. The rolling device for a metal sheet according to any one of (5) to (7) , further comprising: an arithmetic unit that learns the control target value based on the difference between the two.

In the rolling method of the metal sheet material of the present invention described in (1) and (2) , in order to solve the above problems, the force in the rolling direction acting on the work side and driving side roll chocks is measured, The amount of deviation of the rolling material from the center of the rolling mill and the tension are measured on the entry side and / or the exit side of the rolling mill, and the difference between the working side and the driving side of the rolling direction force, that is, the rolling direction A force left / right difference is calculated, the rolling direction force left / right difference is corrected based on the deviation amount and the tension, and the corrected rolling direction force left / right difference is set to a control target value that is normally zero, that is, rolling A method of controlling the camber is proposed by carrying out the reduction leveling control in such a direction that the difference between the directional force left-right difference and the control target value is eliminated, or when the control target value is zero. In this way, by correcting the rolling direction force left / right difference based on the deviation amount and tension of the material to be rolled, even when the tension is acting, the deviation amount and tension of the detected rolling direction force left / right difference are detected. The effect of the moment caused by the action is eliminated, and it is possible to control by using the exact rolling direction force right / left difference value corresponding to the occurrence of meandering and camber, so the meandering and camber control with higher accuracy than before is implemented. be able to.
In the rolling method of the metal plate material of the present invention described in (3) , a method of offsetting the work roll based on the reinforcing roll in the rolling method of the metal plate material described in (1) or (2) is proposed. In the case of this method, since the work roll chock is pressed to the offset side and it is considered that the variation in the measured rolling direction force left-right difference is also reduced, the method for rolling a metal sheet according to either (1) or (2) Can be carried out more stably and with high accuracy.
(4) In the rolling method of the metal plate material of the present invention described in (4) , in the rolling method of the metal plate material according to any one of (1) to (3) , both the entry side and the exit side of the rolling mill of the material to be rolled. Alternatively, a method for learning a control target value by using a plate thickness measured on the exit side and its left-right difference, and a rolling direction force left-right difference corrected based on a deviation amount and tension of a material to be rolled has been proposed. In addition to the influence of the moment generated by the displacement amount and the tension as described above, the influence of disturbance due to roll wear and the like that changes with time can be considered as the difference in the rolling direction force left and right as described above. Therefore, in the case of the method described in (4) , the control target value is set to the correct value based on the measured value of the plate thickness and the difference between the left and right sides after eliminating the influence of the deviation amount of the material to be rolled and the moment caused by the tension. Correction, that is, learning, and using the learned control target value for rolling the next pass, the next pass, or the next material eliminates the influence of disturbance over time due to roll wear, etc., and generates meandering and camber. Since it is possible to control using the exact rolling direction force right / left difference value corresponding to the right / left difference of elongation strain due to rolling, which is the direct cause of rolling, higher-accuracy meandering and camber control can be carried out than before. .

As described above, in the method for rolling a metal sheet according to the present invention described in (1) to (4) , the tension is applied by correcting the rolling direction force left / right difference based on the deviation amount and tension of the material to be rolled. Even in the case where it is possible to eliminate the influence of the moment caused by the amount of deviation and tension exerted on the left-right difference of the detected rolling direction force, and further, the thickness of the material to be rolled after eliminating the influence of the disturbance Since the control target value based on can be learned with high accuracy, it is possible to perform meandering and camber control with higher accuracy than before, and virtually no meandering and camber generation, or very slight meandering and camber rolling can be realized. It becomes.

Next, the effect of this invention regarding the rolling apparatus for implementing the rolling method of the metal plate material of this invention in any one of (1)- (4) is demonstrated.
The rolling device for a metal sheet according to the present invention described in (5) and (6) has the following functions.
1) When load detection devices are provided on both the entry side and the exit side of the roll side of the work roll and the roll chock on the drive side, consider the direction of the load measurement values on both the entry and exit sides. Thus, by calculating the resultant force, it is possible to obtain the rolling direction force acting on the work chock and the drive side roll chock regardless of which direction the force is acting on.
2) If a load detection device is provided on either the entry side or the exit side in the rolling direction of the work roll of the work roll and the drive side roll chock, the load detection device is reinforced on the side provided with the load detection device. By offsetting the work roll on the basis of the roll, a force in the rolling direction always acts on the work roll chock on the offset side, so that the force in the rolling direction acting on the roll chocks on the work side and the drive side can be obtained.
3) Since an arithmetic device for calculating the difference between the work side and the drive side of the rolling direction force acting on the work roll chock is provided, the rolling direction force acting on the work side roll chock and the rolling direction force acting on the drive side roll chock The difference, that is, the difference in rolling direction force can be calculated.
4) Since the apparatus includes a deviation amount detection device that measures the deviation amount of the material to be rolled from the center of the rolling mill on either the entry side or the exit side of the rolling mill or on either side thereof, It is possible to measure the amount of deviation of both or one of the exit sides.
5) Since a tension detector is provided to measure the tension of the material to be rolled on either the entry side or the exit side of the rolling mill, or on the entry side and / or exit side of the material to be rolled. Tension can be measured.
6) Since an arithmetic unit for correcting the rolling direction force left / right difference is provided based on the rolling direction force left / right difference, the shift amount, and the tension, the detected rolling direction even when tension is applied It is possible to eliminate the influence of the moment caused by the amount of deviation and tension on the force lateral difference, and to extract an accurate value of the lateral force difference corresponding to the occurrence of meandering and camber.
7) The moment acting on the work roll from the rolled material due to the left-right difference in elongation strain in the rolling direction causing meandering and camber by eliminating the influence of disturbance by the above correction and obtaining the right-left difference in rolling direction. Can be detected with higher accuracy than in the past.
8) An arithmetic device for calculating a left-right asymmetric component control amount of the roll opening degree of the rolling mill for equalizing the left and right elongation strain based on the corrected rolling direction force left-right difference, and a left-right asymmetric component control amount of the roll opening degree Since the control device for controlling the roll opening degree of the rolling mill is provided based on the calculated value of the meander, the meandering and camber with higher accuracy than the conventional one based on the exact rolling direction force left and right difference corresponding to the occurrence of meandering and camber Control can be implemented.

Eventually, the function described above makes it possible to carry out the method for rolling a metal sheet according to (1) or (2) , and even when tension is applied, meandering and camber with higher accuracy than in the past. Control can be implemented.

In the rolling apparatus of the metal plate material of the present invention described in (7) , in addition to the rolling apparatus described in (5) or (6) , an apparatus for offsetting the work roll to the entry side or the exit side based on the reinforcing roll is provided. Therefore, the work roll chock is pressed to the offset side, and the variation in the measured rolling direction force left-right difference is reduced. Therefore, the rolling method of the metal sheet described in (3) is performed more stably and with high accuracy. can do.

In the rolling apparatus for a metal sheet material of the present invention described in (8) , in addition to the rolling apparatus described in any one of (5) to (7) , the thickness of the work side and the driving side of the material to be rolled is set in the rolling mill. Since a plate thickness measuring device that measures both on the entry side and the exit side or the exit side, and an arithmetic device that learns the control target value based on the difference between the plate thickness and the corrected rolling direction force, are provided. The control target value for learning the influence of disturbance over time caused by roll wear or the like is learned, and the method for rolling a metal sheet according to (4) can be implemented.

  As described above, by using the rolling method and rolling apparatus of the present invention, it is possible to carry out meandering and camber control with higher accuracy than before, so there is no meandering and cambering or very little meandering and cambering. Therefore, it is possible to stably manufacture a metal plate material, and it is possible to realize a significant improvement in productivity and yield in the rolling process of the metal plate material.

  Next, embodiments of the present invention will be described more specifically with reference to the drawings.

FIG. 1 shows a preferred embodiment of a rolling apparatus for realizing the rolling method of the present invention described in (1) or (2) , that is, the rolling apparatus of the present invention described in (5) or (6) . Although FIG. 1 basically shows only the apparatus configuration on the work side, there is a similar apparatus on the drive side. The rolling direction force acting on the upper work roll 1 of the rolling mill is basically supported by the upper work roll chock 5, but the upper work roll chock includes an upper work roll chock outlet load detection device 9 and an upper work roll inlet load detection. The apparatus 10 is provided, and the force acting between a member such as a project block (not shown) that fixes the upper work roll chock in the rolling direction and the upper work roll chock can be measured. In general, these load detection devices preferably have a structure for measuring a compressive force in order to simplify the device configuration. In the upper work roll rolling direction force calculation device 14, the difference between the measurement results of the upper work roll exit side load detection device 9 and the upper work roll entry side load detection device 10 is calculated to calculate the rolling direction force acting on the upper work roll chock 5. To do. Further, the rolling direction force acting on the lower work roll 2 is also measured by the lower work roll outlet load detecting device 11 and the lower work roll inlet load detecting device 12 provided on the outlet side and the inlet side of the lower work roll chock 6. Based on the above, the lower work roll rolling direction force calculation device 15 calculates the rolling direction force acting on the lower work roll chock 6. Next, in the work roll rolling direction resultant force calculation device 16, the sum of the calculation result of the upper work roll rolling direction force calculation device 14 and the calculation result of the lower work roll rolling direction force calculation device 15 is taken, and the rolling direction acting on the upper and lower work rolls Calculate the resultant force. The above procedure is performed not only on the work side but also on the drive side with the same apparatus configuration, and the result is obtained as a work roll rolling direction resultant force 17 on the drive side. Then, the difference between the calculation result on the work side and the calculation result on the drive side is calculated by the work side-drive side rolling direction force difference calculation device 18, and thereby the difference between the work side and the drive side in the rolling direction force acting on the work roll chock. That is, the rolling direction force left-right difference is calculated.

  On the entry side and exit side of the rolling mill, an entry side deviation amount detection device 22 and an exit side deviation amount detection device 23 are provided, and the deviation amounts of the material to be rolled from the center of the entry side and the exit side of the rolling mill are respectively provided. Measured during rolling. Similarly, on the entry side and the exit side of the rolling mill, an entry side tension detection device 24 and an exit side tension measurement device 25 are provided, and the tension on the entry side and the exit side of the material to be rolled are measured during rolling. Is done.

  Next, in the rolling direction force difference correction device 19, the influence of disturbances other than those caused by meandering and camber on the rolling direction force left and right difference based on the rolling direction force left and right difference, the deviation amount and the tension, that is, the material to be rolled Correction of the left-right difference in the rolling direction force is performed in order to eliminate the influence of the moment due to the deviation amount and tension. Hereinafter, the principle of the calculation will be described in detail.

FIG. 4 is a diagram schematically showing the relationship between the rolling direction force left / right difference acting on the work roll chock when tension is applied to the entry side and the exit side of the rolling mill and the moment around the rolling mill center due to the tension distribution. It is. When the difference in elongation of the material to be rolled becomes uneven on the left and right, there is a difference between the left and right of the advance rate and the reverse rate in the roll bite, and there is a difference between the left and right tensions at the front (outside) and rear (inside) of the rolling mill. Arise. Here, the forward and rear tension distributions acting on these materials to be rolled are approximated by straight lines as shown in FIGS. That is, if the working direction (WS) of the material to be rolled is defined as x in the width direction, the front tension per unit cross-sectional area is t ^f , and the rear tension is t ^b , equations (1) and (2 ).

ここで、ｔ_c ^ｆ、ｔ_c ^ｂは前方、後方の板幅中央部の張力（単位断面積あたりの平均張力）、ｔ_df ^ｆ、ｔ_df ^ｂは前方、後方の板幅両端部の張力差、ｘ_c ^ｆ、ｘ_c ^ｂは前方、後方の被圧延材のずれ量すなわちオフセンター量、ｂは板幅である。

Here, t _c ^f and t _c ^b are tensions at the front and rear center portions of the plate width (average tension per unit cross-sectional area), and t _df ^f and t _df ^b are tension differences at both ends of the front and rear plate widths. , X _c ^f , x _c ^b are deviation amounts of the front and rear rolled materials, that is, off-center amounts, and b is a sheet width.

Further, moments M ^f and M ^b around the front and rear rolling mills due to the tension distributions of equations (1) and (2) are calculated by equations (3) and (4).

ここで、ｈ_c ^ｆ、ｈ_c ^ｂは前方、後方の板幅中央部の被圧延材の板厚である。

Here, h _c ^f and h _c ^b are plate thicknesses of the material to be rolled at the front and rear center portions of the plate width.

Also, the rolling direction force left / right difference F _df acting on the work roll chock position Is defined as a value obtained by subtracting the drive side (DS) from the work side (WS) when the direction of the force acting on the exit side of the rolling mill is positive, and the distance a between the fulcrums of the work roll is replaced by moments M ^f and M ^b As

であるから、式(3)、(4)より、下記式(6)を得られる。

Therefore, the following formula (6) can be obtained from the formulas (3) and (4).

式(6)における第一項は、蛇行やキャンバーの原因となる伸び率の左右差に起因して生じる項を示し、第二項は、前記とは別に被圧延材のずれ量と張力の作用によるモーメントによって生じる項を示す。したがって、圧延方向力左右差の実測値より、式(6)の第二項の値を差し引いて補正することで、連続スタンドの圧延機のような入側と出側の双方またはどちらか一方で張力が作用している圧延の場合であっても、蛇行及びキャンバー制御に必要な圧延方向力左右差を抽出することができる。すなわち、補正した圧延方向力左右差Ｆ_df ^ｒは、下記式(7)より求めることができる。

The first term in equation (6) shows the term that arises due to the left-right difference in elongation that causes meandering and camber, and the second term is the effect of the amount of deviation of the material to be rolled and the tension separately from the above. The term generated by the moment due to. Therefore, by subtracting the value of the second term of Equation (6) from the measured value of the difference in rolling direction force left and right, and correcting by subtracting the value on the entry side and the exit side of the continuous stand rolling mill. Even in the case of rolling in which tension is applied, it is possible to extract the difference in the rolling direction force necessary for meandering and camber control. That is, the corrected rolling direction force left-right difference F _df ^r can be obtained from the following equation (7).

ここで、Ｆ_df ^mは圧延方向力左右差の実測値、Ｔ^fm、Ｔ^bmは前方、後方張力の実測値、
ｘ_c ^fm、ｘ_c ^bmは前方、後方の被圧延材のずれ量の実測値である。

Here, F _df ^m is an actual measurement value of the rolling direction force left and right difference, T ^fm and T ^bm are actual measurement values of front and rear tensions,
x _c ^fm and x _c ^bm are actual measurement values of the deviation amounts of the front and rear rolled materials.

  Based on the calculation result of the rolling direction force left / right difference corrected by the rolling direction force difference correction device 19 as described above, the corrected rolling direction force left / right difference is an appropriate control target value 29 in the rolling leveling control amount calculation device 20. Calculate the left-right asymmetric component control amount of the roll opening of the rolling mill to prevent meandering and camber so that the difference between the rolling direction force left-right difference and the control target value is eliminated. . Here, “normal” means that there is no influence of left-right asymmetrical disturbances such as the left-right difference in friction coefficient due to roll wear, and the difference in rolling direction force left and right corrected from the amount of rolling material and tension causes the occurrence of meandering and camber. This is a case of one-to-one correspondence with the left-right difference in elongation strain that directly causes the above. In addition, “zero” includes a range in which the corrected rolling direction force left-right difference is so small that occurrence of meandering or camber is negligible.

Here, based on the rolling direction force left-right difference, for example, the control amount is calculated by PID calculation considering a proportional (P) gain, an integral (I) gain, and a differential (D) gain. In other words, when a digital PID control system is considered, it can be expressed by the following equation. The left-right asymmetric component control amount S _df ^C (k) of the roll opening per sampling is expressed by the following equation.

そしてこの制御量演算結果に基づいて、圧下レベリング制御装置２１によって圧延機のロール開度の左右非対称成分を制御することで蛇行及びキャンバー発生のない、あるいは極めて蛇行及びキャンバーの軽微な圧延が実現できる。

And based on this control amount calculation result, the rolling leveling control device 21 controls the left-right asymmetric component of the roll opening of the rolling mill so that no meandering and camber generation or extremely slight meandering and camber rolling can be realized. .

In the above example, the tension is applied to both the entry side and the exit side of the rolling mill.For example, when the tip of the rolled material passes through during continuous hot rolling, That is, even when the front tension is not loaded as shown in FIG. 7 or when the tail end of the rolled material passes, that is, when the rear tension is not loaded as shown in FIG. Similarly, by setting the value of the front tension T ^fm or the rear tension T ^bm in (7) to zero, or when there is no deviation amount detection device or tension detection device on both the entry side and the exit side of the rolling mill. The correction value of the rolling direction force left-right difference can be obtained.

FIG. 2 shows another preferred embodiment of a rolling device relating to the rolling method of the present invention described in (1) or (2) , that is, the rolling device of the present invention described in (5) or (6) . In the embodiment of FIG. 2, compared with the embodiment of FIG. 1, the deviation amount detection device on the rolling mill exit side is omitted, and further, the detection device and arithmetic device for the rolling direction force acting on the lower work roll chock are omitted. Yes. In the steady state rolling state where tension is applied to the entry side and the exit side of the rolling mill, the amount of deviation on the entry side and the exit side is almost the same unless there is a sudden skew of the material to be rolled before and after the rolling mill. Since it can be regarded, it is possible to correct the difference in the rolling direction force left and right in the same manner based on the shift amount on the entry side only. In general, the moment that acts on the work roll from the rolled material due to the left-right difference in the elongation strain and the moment due to the deviation and tension of the material to be rolled do not necessarily act equally on the upper and lower work rolls. Regarding the change behavior, the trend does not reverse between the upper and lower work rolls, and therefore, by correcting the rolling direction force left / right difference based on the deviation amount and tension of the material to be rolled, it is included in the measured value of the rolling direction force left / right difference. The influence of disturbances other than those caused by meandering and camber can be eliminated, and good meandering and camber control based on the right and left difference in the rolling direction force corresponding to the occurrence of meandering and camber can be realized.

FIG. 3 shows a preferred embodiment of a rolling apparatus for realizing the rolling method of the present invention described in (3) , that is, the rolling apparatus of the present invention described in (7) . In the embodiment of FIG. 3, the work roll is offset to the outlet side with respect to the reinforcing roll. In this case, since the force in the rolling direction always acts on the work roll chock on the offset side, the force in the rolling direction acting on the roll chocks on the work side and the drive side is obtained even when there is no load detection device on the rolling mill entry side. be able to. Furthermore, in this case, it is considered that the work roll chock is pressed to the offset side, and the variation in the measured rolling direction force left-right difference is reduced. And by correcting the rolling direction force left / right difference based on the deviation and tension of the material to be rolled, it is possible to eliminate the influence of disturbances other than those caused by meandering and camber included in the measured value of the rolling direction force left / right difference. Thus, it is possible to realize good meandering and camber control based on the right and left difference in the rolling direction force corresponding to the occurrence of meandering and camber.

FIG. 9 shows a preferred embodiment of the rolling apparatus for realizing the rolling method of the present invention described in (4) , that is, the rolling apparatus of the present invention described in (8) . In the embodiment of FIG. 9, the control target value of the rolling direction force left / right difference is learned as follows. From the entrance side plate thickness measuring device 30 and the exit side plate thickness measuring device 31 of the rolling mill shown in FIG. 9, the entrance side thickness and the exit side plate thickness on the working side and drive side of the material to be rolled during or after rolling are determined. Measured. Rolling direction force left / right difference is a value caused by left / right difference in elongation strain in the rolling direction caused by rolling, so the difference between the rolled sheet thickness on the working side and the drive side, that is, the sheet thickness wedge as an index, or on the entry / exit side The control target value can be learned by evaluating, as an index, a change in the thickness wedge ratio in consideration of the influence of the above.

  Here, the difference between the plate thickness on the working side and the drive side, that is, the definition of the plate thickness wedge and the plate thickness wedge ratio change will be described.

The difference in plate thickness between the working side and the drive side, that is, the plate thickness wedge h _df ^def can be expressed by the following equation.

ここで、h_WS ^defが作業側の板厚、h_DS ^defが駆動側の板厚である。
また、板厚ウェッジ比率変化ΔΨは、次式で表せる。

Here, h _WS ^def is the plate thickness on the working side, and h _DS ^def is the plate thickness on the drive side.
Further, the plate thickness wedge ratio change ΔΨ can be expressed by the following equation.

ここで、H_dfが入側の板厚ウェッジ、h_df が出側の板厚ウェッジ、Hが入側の板厚、ｈが出側の板厚である。
なお、ここでは、板厚ウェッジ比率変化を指標とした場合の圧延方向力左右差の制御目標値の学習法について説明する。

Here, H _df is the inlet side thickness wedge, h _df is the outlet side thickness wedge, H is the inlet side thickness, and h is the outlet side thickness.
Here, a learning method of the control target value of the rolling direction force left-right difference when the change in the thickness wedge ratio is used as an index will be described.

In the control target value calculation device 32, based on the work-side and drive-side entrance-side and exit-side plate thicknesses of the material to be rolled measured by the entrance-side plate thickness measuring device 30 and the exit-side plate thickness measuring device 31, The plate thickness wedge ratio change is calculated based on Equation (10). Further, the control target value calculation device 32 calculates the rolling direction force left / right difference corrected by the rolling direction force difference correction device 19 and the calculation so as to correct the influence of the temporal disturbance caused by the wear of the roll and the like. Based on the change in the plate thickness wedge ratio, the control target value 29 in the rolling of the pass, the next pass or the next material is calculated. At this time, a relational expression between the corrected rolling direction force left-right difference F _df ^r and the plate thickness wedge ratio change ΔΨ is obtained in advance, for example, before actual rolling as shown in the following formula (11), for learning. Use.

ここで、a、bは、予め求めておいた定数である。
上記式(11)より、当該圧における板厚ウェッジ比率変化の実測値をΔΨ^M、補正された圧延方向力左右差の実測値をF_df ^rMとすると、当該圧延において修正される制御目標値C_rは、下記(12)式から演算される。

Here, a and b are constants obtained in advance.
From the above equation (11), if the actual measurement value of the plate thickness wedge ratio change at the pressure is ΔΨ ^M and the actual measurement value of the corrected rolling direction force left-right difference is F _df ^rM , the control target value C corrected in the rolling. _r is calculated from the following equation (12).

なお、この制御目標値は、圧延本数が増加するに従って学習し変更していく必要があるので、例えば、下記式(13)を用いてパス毎または圧延材本数毎に学習すれば良い。

Since this control target value needs to be learned and changed as the number of rolled sheets increases, for example, the control target value may be learned for each pass or number of rolled materials using the following equation (13).

ただし、Ｃ(n)はnパス目または圧延材ｎ本目の制御目標値、 Ｃ_r(n)はnパス目または圧延材ｎ本目の修正された制御目標値、γは学習ゲイン(0〜1.0)である。
なお、上記では、入出側双方の板厚測定値により演算した板厚ウェッジ比率変化に基づく学習法について説明したが、入側に板厚測定装置がない場合は、出側の板厚ウェッジのみを用いて学習する方法でも、前記の方法に比べ学習精度は低下するものの、式(13)における学習ゲインγの値を小さくする等の調整を行うことで、十分適用することができる。

However, C (n) is the control target value of the nth pass or the nth rolled material, _Cr (n) is the corrected control target value of the nth pass or the nth rolled material, and γ is the learning gain (0 to 1.0). ).
In the above description, the learning method based on the change in the thickness wedge ratio calculated from the measured thickness values on both the input and output sides has been described. However, if there is no thickness measurement device on the input side, only the output thickness wedge is used. Although the learning method using the method is less accurate than the above method, it can be sufficiently applied by making adjustments such as reducing the value of the learning gain γ in Equation (13).

As described above, in the rolling method of the present invention described in (4) , based on the measured value of the plate thickness, after eliminating the influence of the deviation amount of the material to be rolled and the moment caused by the tension, which have not been considered in the past. The control target value is learned, and the learned control target value is used for rolling the relevant pass, the next pass or the next material, thereby eliminating the influence of disturbance over time caused by roll wear and the like, meandering and camber Since it can be controlled using the exact rolling direction force left / right difference value corresponding to the left / right difference in elongation strain due to rolling, which is the direct cause of occurrence, higher accuracy meandering and camber control than before can be implemented it can.

Example when the rolling method described in (1) or (2) of the present invention is applied to the final stand of a hot finishing mill having the same function as the rolling apparatus shown in FIG. 1 (Invention Example 1) Will be described. The camber control based on the difference in the rolling direction force was performed by the present invention and the conventional method when the tip portion with a back tension applied was passed. In the method of the present invention, the rolling direction force left / right difference is corrected based on the measured values of the deviation amount detecting device and the tension detecting device installed on the entry side of the rolling mill, and the rolling leveling is reduced based on the corrected rolling direction force left / right difference. Control was implemented. On the other hand, in the conventional method, the reduction leveling control was performed based on the measured rolling direction force left / right difference without performing the above correction.

  Table 1 shows the measured value of the camber with respect to the number of representative rolls in Example 1 of the present invention for each result of the present invention and the conventional method. As shown in Table 1, it can be seen that the actual camber value per meter is suppressed to a relatively small value of 0.15 mm / m in the present invention. On the other hand, in the case of the conventional method, it can be seen that the actual camber value is large in any number of rollings. In the case of the present invention, the influence of disturbance is eliminated by correcting the rolling direction force left / right difference based on the deviation amount and tension of the material to be rolled, but in the conventional method, these error factors are included in the rolling direction force left / right difference. Therefore, it is considered that the actual camber value is larger than that of the method of the present invention.

  As described above, by using the rolling method and the rolling apparatus of the present invention, camber control with higher accuracy than before can be performed, so that it was confirmed that extremely light camber rolling can be realized.

Example when the rolling method described in (1) or (2) of the present invention is applied to the final stand of a hot finishing mill having the same function as the rolling apparatus shown in FIG. 1 (Example 2 of the present invention) Will be described. The meandering control based on the difference in the rolling direction force between the present invention and the conventional method was performed during rolling of the steady portion where the forward and backward tensions were applied.

  First, in the conventional method, the rolling leveling control is performed based on the difference in the rolling direction force left and right as measured without correction during steady-state rolling. As a result, the meandering amount at the time of steady part rolling is about 20 mm, and when the tail end of the rolled material passes through a rolling mill, when a thin wide material having a thickness of 1.2 mm and a width of 1200 mm is rolled. A large meander and narrowing occurred.

  On the other hand, in the rolling method of Example 2 of the present invention, the rolling direction force left / right difference is corrected based on the measurement values of the deviation amount detection device and the tension detection device installed on the entry side and the exit side of the rolling mill, and the corrected rolling direction Rolling leveling control was performed during rolling of the steady part based on the difference between left and right forces. As a result, the amount of meandering during rolling of the steady part is suppressed to within 10 mm as in the conventional method with a single stand, and further, a thin and wide material having a thickness of 1.2 mm and a width of 1200 mm on the exit side where narrowing has occurred in the conventional method. Even in the case of rolling, it was possible to pass the rolled material straight through the rolling line, and to realize a stable rolling operation with no accidents when rolling the rolled material.

  As described above, by using the rolling method and rolling apparatus of the present invention, it is possible to perform meandering control with higher accuracy than in the past, so that the tail end of the rolled material passes through the rolling mill. It was verified that meandering can be suppressed and narrowing down can be prevented.

An embodiment in which the rolling method described in (4) of the present invention is applied to the final stand of a hot finishing mill having the same function as the rolling apparatus shown in FIG. 9 will be described (Invention Example 3). The meandering control based on the difference in the rolling direction force between the present invention and the conventional method was performed during rolling of the steady portion where the forward and backward tensions were applied.

  First, in the conventional method, the rolling leveling control is performed based on the difference in the rolling direction force left and right as measured without correction during steady-state rolling. As a result, the meandering amount at the time of steady part rolling is about 20 mm, and when the tail end of the rolled material passes through a rolling mill, when a thin wide material having a thickness of 1.2 mm and a width of 1200 mm is rolled. A large meander and narrowing occurred.

  On the other hand, in the rolling method of Example 3 of the present invention, the rolling direction force left / right difference is corrected based on the measured values of the deviation detecting device and the tension detecting device installed on the entry side and the exit side of the rolling mill, and the corrected rolling direction Rolling leveling control is carried out during rolling of the steady part based on the force difference between the left and right sides, and the measured thickness values on the inlet and outlet sides of the thickness measuring device installed on the inlet side and outlet side of the rolling mill and the corrected rolling The control target value is learned based on the directional force left / right difference with a learning gain γ = 0.3 for each rolled material.

  As a result, even in the state after rolling the 300 rolled materials just before the work rolls are rearranged, the amount of meandering during the steady portion rolling is suppressed to 10 mm or less as in the conventional method with a single stand, Even when rolling out a thin wide material with a thickness of 1.2 mm and a width of 1200 mm, which has been narrowed down by the conventional method, the rolled material can be passed straight through the rolling line, causing an accident when rolling the rolled material. No stable rolling operation could be realized.

  As described above, by using the rolling method and rolling apparatus of the present invention, meandering control with higher accuracy than before is performed on all rolled materials from the start of rolling to the end of rolling immediately before the work roll replacement. Therefore, it was verified that the tail end portion of the rolled material can suppress the meandering when passing through the rolling mill and prevent narrowing.

Examples (Example 4 of the present invention, Example 5 of the present invention ) when the rolling method described in (4) of the present invention is applied to the rolling device of the final stand of the hot finishing mill shown in FIG. 10 will be described. In the rolling apparatus shown in FIG. 10, compared with the rolling apparatus shown in FIG. 9, a deviation amount detecting device on the outlet side of the rolling mill and a sheet thickness measuring device on the inlet side of the rolling mill are omitted. The camber control based on the difference in the rolling direction force was performed between the method of the present invention and the conventional method when passing through the tip portion where the rear tension was applied.

  First, in the conventional method, the reduction leveling control is performed based on the left-right difference in the rolling direction force as it is measured without correction at the time of passing the tip portion. On the other hand, in the present invention, the rolling direction force left / right difference is corrected based on the measured values of the deviation amount detection device and the tension detection device installed on the entry side of the rolling mill, and based on the corrected rolling direction force left / right difference. The reduction leveling control was implemented. This method is referred to as Example 4 of the present invention. Furthermore, learning of the control target value was carried out with a learning gain γ = 0.15 for each rolled material based on the plate thickness measurement value of the plate thickness measuring device installed on the exit side of the rolling mill and the corrected rolling direction force left-right difference. Since there is no information on the entry side plate thickness, there is a concern that the learning accuracy may be slightly deteriorated, so the learning gain is set to a smaller value than when the plate thickness information on both the entry and exit sides is obtained. This method is referred to as Example 5 of the present invention.

  Table 2 shows the measured values of the camber with respect to the number of representative rolls in this example for each result of the present invention and the conventional method. As shown in Table 2, the actual measured value of camber per 1 m is suppressed to a relatively small value of 0.15 mm / m up to the 100th rolling in the case of Invention Example 4 and Invention Example 5. Recognize. On the other hand, in the case of the conventional method, it can be seen that the actual camber value is large in any number of rollings. In the case of the present invention, the influence of disturbance is eliminated by correcting the rolling direction force left / right difference based on the deviation amount and tension of the material to be rolled, but in the conventional method, these error factors are included in the rolling direction force left / right difference. Therefore, it is considered that the actual camber value is larger than that of the method of the present invention. Further, in the case of the present invention example 5, after eliminating the influence of the deviation amount of the material to be rolled and the moment due to the tension, the control target value is learned based on the measured value of the plate thickness, and the learned control target value is It was confirmed that the camber was suppressed to a relatively small value of 0.15 mm / m up to the number of 300 rolled by using the next material for rolling.

  As described above, by using the rolling method and rolling apparatus of the present invention, high-accuracy camber control is performed on all rolled materials from the start of rolling to the end of rolling immediately before the work roll replacement. As a result, it was confirmed that extremely light rolling of the camber could be realized.

  In the above embodiment, an example of the learning method based on the measured value of the plate thickness is shown. However, if the equipment has a camber meter on both the entry side and the exit side or the exit side of the rolling mill, the material to be rolled Needless to say, the same learning can be performed based on, for example, a change in camber curvature or an actual measured value of the camber on the output side instead of the measured value of the plate thickness after correcting the influence of the deviation amount and the tension.

It is a figure which shows typically preferable embodiment of the rolling apparatus of this invention as described in the rolling apparatus (5) or (6) which implement | achieves the rolling method of this invention as described in (1) or (2) . It is a figure which shows typically preferable embodiment of the rolling apparatus of this invention as described in the rolling apparatus (5) or (6) which implement | achieves the rolling method of this invention as described in (1) or (2) . It is a figure which shows typically preferable embodiment of the rolling apparatus of this invention as described in the rolling apparatus (7) which implement | achieves the rolling method of this invention as described in (3) . It is the figure which showed typically the relationship between the moment around the center of a rolling mill by a rolling direction force left-right difference which acts on the work roll chock when tension | tensile_strength is loaded ahead and the back of a rolling mill, and tension distribution. It is the figure which showed typically the definition at the time of approximating the tension distribution which acts ahead of a to-be-rolled material with a straight line. It is the figure which showed typically the definition at the time of approximating the tension distribution which acts on the back of a rolling material with a straight line. It is the figure which showed typically the relationship between the rolling direction force left-right difference which acts on the work roll chock when the tension | tensile_strength is loaded ahead of the rolling mill, and the moment around the rolling mill center by tension distribution. It is the figure which showed typically the relationship between the rolling direction force left-right difference which acts on the work roll chock when tension | tensile_strength is loaded behind the rolling mill, and the moment around the rolling mill center by tension distribution. It is a figure which shows typically preferable embodiment of the rolling apparatus of this invention as described in the rolling apparatus (8) which implement | achieves the rolling method of this invention as described in (4) . It is a figure which shows typically preferable embodiment of the rolling apparatus of this invention as described in the rolling apparatus (8) which implement | achieves the rolling method of this invention as described in (4) .

Explanation of symbols

1 Upper work roll 2 Lower work roll 3 Upper reinforcement roll 4 Lower reinforcement roll 5 Upper work roll chock (working side)
6 Lower work roll chock (work side)
7 Upper reinforcement roll chock (working side)
8 Lower reinforcement roll chock (working side)
9 Upper work roll outlet load detector (work side)
10 Upper work roll entry side load detection device (work side)
11 Lower work roll exit side load detector (work side)
12 Lower work roll entry side load detector (work side)
13 Reduction device 14 Upper work roll rolling direction force calculation device (work side)
15 Lower work roll rolling direction force calculation device (work side)
16 Work roll rolling direction resultant force calculation device [adder] (work side)
17 Work roll rolling direction resultant force (drive side)
18 Work side-drive side rolling direction force difference calculation device [subtractor]
DESCRIPTION OF SYMBOLS 19 Rolling direction force difference correction apparatus 20 Rolling leveling control amount calculation apparatus 21 Rolling leveling control apparatus 22 Entry side deviation | shift amount detection apparatus 23 Outlet side deviation | shift detection apparatus 24 Entry side tension detection apparatus 25 Egress side tension detection apparatus 26 Metal plate material 27 Rolling Direction 28 Upper work roll rolling direction force (drive side)
29 control target value 30 inlet side plate thickness measuring device 31 outlet side plate thickness measuring device 32 control target value calculating device

Claims (8)

In the rolling method of the metal plate material performed using a rolling machine of the metal plate material having at least a work roll and a reinforcing roll,
Measure the rolling direction force acting on the work side and drive side roll chock of the work roll,
Measure the amount of deviation of the material to be rolled from the center of the rolling mill on either the entry side or the exit side of the rolling mill, or either
Measure the tension of the material to be rolled on the entry side and / or exit side of the rolling mill,
The difference between the working side and the driving side of the rolling direction force (hereinafter referred to as the difference) is calculated, and the difference is corrected by the deviation amount and the tension,
The left-right asymmetric component control amount is calculated so that the corrected difference becomes a control target value that is normally zero ,
A rolling method for a metal plate material, wherein a left-right asymmetric component of a roll opening degree of the rolling mill is controlled based on the control amount. When correcting the difference between the working side and the driving side of the rolling direction force, determined moment on the basis of the shift amount and the tension, and corrects the difference based on the moment claim The rolling method of the metal plate material of 1 . The method for rolling a metal sheet according to claim 1 , wherein the work roll is offset to a rolling entry side or a rolling exit side with the reinforcing roll as a reference. The thickness of the work side and the drive side of the material to be rolled is measured on both the entry side and the exit side or the exit side of the rolling mill, and the control target is based on the difference between the plate thickness and the corrected rolling direction force. The method of rolling a metal sheet according to any one of claims 1 to 3 , wherein a value is learned. In a rolling apparatus having a rolling mill for a metal plate material provided with at least a work roll and a reinforcing roll,
A load detecting device provided on both or one of the entry side and the exit side in the rolling direction of the roll chock, which is a detection device that measures the rolling direction force acting on the work side and drive side roll chock of the work roll; ,
A deviation amount detecting device for measuring a deviation amount of the material to be rolled from the center of the rolling mill on either or both of the entry side and the exit side of the rolling mill;
A tension detection device that measures the tension of the material to be rolled on either or both of the entry side and the exit side of the rolling mill;
An arithmetic device for calculating a difference in rolling direction force between the working side and the driving side acting on the roll chock;
A correction device for correcting the difference based on the shift amount and the tension;
It has a control device that controls the roll opening of the rolling mill based on the calculated value of the left-right asymmetric component control amount of the roll opening so that the corrected difference becomes a control target value that is normally zero. And a metal sheet rolling apparatus. 6. The metal plate material according to claim 5 , wherein the arithmetic device that corrects the difference is an arithmetic device that calculates a moment based on the shift amount and the tension, and corrects the difference based on the moment. Rolling equipment. The rolling device for a metal sheet according to claim 5 or 6 , wherein the work roll is offset to a rolling entry side or a rolling exit side with respect to the reinforcing roll. A thickness measuring device for measuring the thickness of the work side and the driving side of the material to be rolled on both the entry side and the exit side of the rolling mill or the exit side, and the difference between the thickness and the corrected rolling direction force The rolling device for a metal sheet according to any one of claims 5 to 7 , further comprising an arithmetic device that learns the control target value based on the calculation device.

Images