JP3499107B2 - Plate rolling method and plate rolling machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling method for rolling a metal plate material such as steel and a rolling mill facility therefor.

[0002]

2. Description of the Related Art One of the important problems in the rolling operation of a metal sheet is to make the elongation rate of the rolled material equal on the working side and the driving side. In the following, the working side and the driving side will be referred to as left and right for the sake of simplicity. If the elongations are not uniform on the left and right, not only the planar shape and dimensional accuracy of the rolled material such as the camber and the plate thickness wedge may be inferior, but also the passing problem such as meandering and tail drawing may occur.

As an operating means for equalizing the left and right elongations, a left-right difference in the rolling position of the rolling mill, that is, a rolling leveling operation is used. Usually, the operation of the rolling leveling, both before the rolling and during the rolling, is almost always done by the operator while carefully observing the rolling operation. It cannot be said that the trouble of passing the strip is sufficiently controlled.

Japanese Patent Publication No. 58-51771 discloses a technique of performing reduction leveling control based on the ratio of the load cell load of a rolling mill to the sum of the left-right difference of the rolling mill. Contains various disturbances in addition to the influence of the amount of meandering of the rolled material, and the control based on the ratio of the above-mentioned left and right difference may be a control that promotes meandering, which is a sufficient effect. Not up to.

Further, Japanese Laid-Open Patent Publication No. 59-191510 discloses a technique for operating the reduction leveling by directly detecting the deviation of the rolled material on the rolling mill entrance side, that is, the amount of meandering. When rolling long strips or tandem rolling, even if the reduction leveling is not appropriate, the actual weight of rolling strips upstream of the rolling mill and the constraint conditions of the rolling mills upstream of the rolling mill cause In most cases, the rolling material on the side does not meander, and in such a case, the amount of meandering cannot be detected even though there is defective rolling leveling. Can not be used as a means to control. Further, for example, even when detecting the meandering amount on the rolling material delivery side, the detected value includes the width due to the left / right difference in the delivery material speed of the rolling mill and the movement of the rolling material camber already existing on the rolling mill delivery side. Since the directional displacement is superimposed, it is difficult to use it for optimizing the reduction leveling control to equalize the elongation of the rolled material in the roll bite of the rolling mill at the time of measuring the meandering amount. is there.

[0006]

As described above, the method for directly detecting the amount of meandering cannot directly optimize the reduction leveling and that the phenomenon occurring in the roll bite can be directly detected. Since it is not a measurement, there is an essential drawback in that disturbance is likely to occur and that time delay also occurs in the reduction leveling control.

On the other hand, the difference between the rolling loads on the left and right conveys the information on the left-right asymmetry of the phenomenon occurring in the roll bite without any time delay, and can be the most important information for the optimum control of the reduction leveling. Therefore, in the present invention, the disturbance included in the left-right difference of the rolling load detected from the load cell is specified, and the left-right difference of the rolling phenomenon occurring between the rolled material and the work roll is accurately estimated to optimize the rolling leveling. A plate rolling method for achieving the above and a plate rolling machine for realizing the same are disclosed.

[0008]

As a result of thorough investigation and analytical study, the inventors of the present invention have found that the difference between the rolling loads measured by the load cell of the rolling mill includes the rolling load distribution between the rolled material and the work rolls. In addition to the left-right asymmetry with respect to the mill center, for example, between a work roll and a reinforcing roll in the case of a four-high rolling mill, a work roll and an intermediate roll in the case of a six-high rolling mill,
It was found that the thrust force acting between the intermediate roll and the reinforcing roll in the roll axial direction was included as the largest factor. The thrust force acting between these rolls gives an extra moment to the rolls, and the rolling load difference between left and right changes to balance this moment, so the difference between the left and right load measured by the load cell of the rolling mill ~ It becomes a serious disturbance for the purpose of grasping the left-right asymmetry of the rolling load distribution occurring between the work rolls.
Further, this roll-to-roll thrust force may be reversed not only in its magnitude during the rolling operation but also in the direction in some cases, so that it is very difficult to accurately estimate it in advance. In most cases, the rolling zero point adjustment of the rolling mill is carried out by tightening the kiss roll to a predetermined zero-adjustment load. The thrust force of is added as a disturbance. In the reduction zero point adjustment, the reduction position is reset so that the loads measured by the load cells on the working side and the driving side become equal to a predetermined load, and the zero point of the reduction leveling is reset at the same time. At this time, if the roll-to-roll thrust force as described above acts and the left-right difference of the load cell load includes disturbance, accurate zero point adjustment of the reduction leveling cannot be performed, and the subsequent reduction leveling setting is always performed. This zero point error is included. Further, as disclosed in Japanese Patent Laid-Open No. 6-182418, a kiss roll tightening test is also performed when grasping the left-right asymmetry of the rolling mill rigidity, that is, the deformation characteristic of the rolling mill with respect to the mill center. However, the above-mentioned thrust force between rolls causes a serious error.

The present invention has solved the above-mentioned various problems, and its gist is as follows. (1) In a rolling method using a multi-high rolling mill having four or more stages, in the tightened state of kiss rolls, the measured values of the roll axial thrust reaction force acting on at least all rolls other than the reinforcing rolls and the upper and lower reinforcing rolls are measured. From the measured value of the reinforcing roll reaction force acting in the rolling direction at the rolling fulcrum position,
A plate rolling method characterized in that either or both of a zero point of a rolling device and a deformation characteristic of a rolling mill are obtained, and based on this, a rolling position is set and / or controlled during execution of rolling.

[0010] (2) rolling using four or more stages of the multi-stage rolling mill
Method, the measured values of the roll axial thrust reaction force acting on all rolls other than the reinforcing roll in the upper or lower roll assembly or both upper and lower roll assemblies, and the reinforcement acting in the rolling direction at each rolling fulcrum position of the reinforcing roll. From the measured value of the roll reaction force, calculate the target value of the rolling position operation amount of the rolling mill, based on the target value of the rolling position operation amount,
A strip rolling method characterized by performing a rolling position control.

[0011] (3) rolling using four or more stages of the multi-stage rolling mill
Method, the measured values of the roll axial thrust reaction force acting on all rolls other than the reinforcing roll in the upper or lower roll assembly or both upper and lower roll assemblies, and the reinforcement acting in the rolling direction at each rolling fulcrum position of the reinforcing roll. From the measured value of the roll reaction force, at least the asymmetry with respect to the mill center of the roll axial distribution of the load acting between the rolled material and the work roll is calculated, and based on the calculation result, the rolling position operation amount of the rolling mill is calculated. A plate rolling method, wherein a target value is calculated, and the reduction position control is performed based on the target value of the reduction position operation amount.

(4) In a multi-high plate rolling mill having four or more stages, a roll axial thrust reaction force measuring device acting on all rolls other than the reinforcing rolls, and acting in the rolling direction at each rolling fulcrum position of the upper and lower reinforcing rolls. And a reinforcing roll reaction force measuring device. (5) In a multi-high rolling mill having four or more stages, a roll axial thrust reaction force measuring device that acts on all rolls other than the reinforcing rolls, and a reinforcing roll that acts in the rolling direction at each rolling fulcrum position of the upper and lower reinforcing rolls. A reaction force measuring device, at least the thrust reaction force measurement value and the reinforcing roll reaction force measurement value as input data, at least the asymmetry about the mill center of the roll axial distribution of the load acting between the rolling material and the work roll Or a computing device for computing the asymmetry of the roll axial distribution of the load acting between the upper and lower work rolls with respect to the mill center.

(6) A roll bending device is provided for at least one set of rolls other than the reinforcing rolls, and at least one roll chock among the rolls having the roll bending device has a roll chock that supports a radial load and a roll chock. It has a structure in which it is separated into roll chock that supports the thrust reaction force in the axial direction, and a device for measuring the thrust reaction force acting on the roll chock for supporting the thrust reaction force is provided.
The plate rolling mill according to (4) or (5) above .

(7) A roll bending device is provided on at least one set of rolls other than the reinforcing rolls, and a mechanism capable of adding a vibration component having a frequency of 5 Hz or higher to the set roll bending force is provided.
The plate rolling mill according to (4) or (5) . (8) A roll bending device is provided on at least one set of rolls other than the reinforcing rolls, and the roll bending device has a roll axial direction between a load applying part of the roll bending device and a roll chock abutting the load applying part. The plate rolling machine according to (4) or (5) above, which has a slide bearing mechanism having a degree of freedom.

(9) A roll bending device is provided on at least one set of rolls other than the reinforcing rolls, and an elasticity against out-of-plane deformation is provided between the load loading part of the roll bending device and the roll chock abutting against the load loading part. on deformation resistance characterized by having a load transmitting portion of the arrangement in which liquid is sealed in a closed space at least partially covered with 5% thin outer skin of the maximum value of the roll bending force
The strip rolling mill according to item (4) or (5) .

(10) At least one set of rolls other than the reinforcing rolls has a mechanism for axially shifting the rolls,
On the shift mechanism at least amplitude 1 mm, characterized by a function that gives the following minute shift swing cycle 30 seconds
The strip rolling mill according to any one of (4) to (9) .

According to the first aspect of the present invention, a means for separating the disturbance due to the thrust force between the rolls is disclosed particularly when adjusting the rolling zero point by tightening the kiss roll and extracting the lateral asymmetry of the deformation characteristic of the rolling mill. . According to the first aspect, when tightening the kiss roll, the thrust reaction force acting on the rolls other than the reinforcing rolls and the reinforcing roll reaction force acting on the respective rolling fulcrum positions of the upper and lower reinforcing rolls are measured. Here, the thrust reaction force is to hold the roll in place against the resultant force of each roll mainly due to the existence of a minute cross angle between the rolls on the contact surface of each roll body. Is generated on the keeper plate through the roll chock, but in the case of a rolling mill having a roll axial shift device, the shift force is generated on the shift device. In addition, the reinforcing roll reaction force acting on each rolling fulcrum position of the upper and lower reinforcing rolls is usually measured by a load cell, but when a hydraulic rolling down device is provided, it may be calculated from the measured value of the pressure in the rolling down cylinder. By measuring the thrust reaction force and the reinforcing roll reaction force, for example, in the case of a four-high rolling mill, the unknown number of the force acting on each roll and the force involved in the equilibrium condition of the moment is the following eight. Becomes

T _B ^T : Thrust reaction force acting on upper reinforcing roll chock T _WB ^T : Thrust force acting between upper work roll and reinforcing roll T _WW : Thrust force acting between upper and lower work rolls T _WB ^B : Lower work thrust T _B ^B acting between the rolls - rolls: thrust counterforces acting on the lower reinforcing roll chocks p ^df _WB ^T: top work roll - reinforcing laterality p ^df _WB line load distribution between rolls ^B: lower work rolls ^{-Left and} right difference of line load distribution between reinforcing rolls p ^df _WW : Left and right difference of line load distribution between upper and lower work rolls Here, the line load distribution is a roll axial distribution of tightening load acting on each roll body. That is, the load per unit body length is called a line load. Needless to say, if it is possible to measure the thrust reaction force acting on the roll chock of the reinforcing roll, it is possible to calculate with higher accuracy, which is preferable, but the roll chock of the reinforcing roll produces a reaction force much larger than the thrust reaction force. Since the thrust reaction force is received at the same time, it is generally not easy to measure the thrust reaction force, and the measurement value of the thrust reaction force of the reinforcing rolls is not available here. If the thrust reaction force of the reinforcing roll can be measured, the number of equations will be greater than the number of unknowns in the following explanation, so if the unknowns are obtained as the least squares solution of all equations, the calculation accuracy will be It will be improved.

The equations that can be used to obtain the above-mentioned eight unknowns are a total of eight equations, that is, four equilibrium conditional expressions for the force in the roll axial direction of each roll and four equilibrium conditional expressions for the moment of each roll. . It is assumed here that the vertical force equilibrium condition expression of each roll has already been taken into consideration, and unknown factors are excluded from those involved in the vertical force equilibrium condition expression. By solving the equilibrium condition equation of the force and moment of each roll with respect to the above eight unknowns, it becomes possible to obtain all the above unknowns.

By obtaining all the forces related to the left-right asymmetry about the mill center as described above,
It is possible to calculate the roll deformation accurately including the left-right asymmetry. By subtracting the roll deformation contribution independently from the mill stretch amount obtained from the relationship between the tightening load and the rolling position when tightening the kiss roll, It is possible to accurately obtain the deformation characteristics of the left and right housings and the rolling system.

On the other hand, with regard to the zero point of the rolling down device, a true left-right uniform rolling down is generated when the inter-roll thrust force is not generated by the left-right difference of the roll flatness caused by the left-right difference of the linear load distribution acting between the rolls. Since it is displaced from the position, the error amount may be always corrected when the reduction is set, or more practically, the zero point itself may be corrected in consideration of the error amount. In any case, it is necessary to measure the reaction force of the reinforcing roll at each rolling fulcrum position of the reinforcing roll and the thrust reaction force other than that of the reinforcing roll to estimate the left-right difference in the line load distribution between the rolls. Even if any of the above measurement values is missing, the unknown number becomes eight or more, and it becomes impossible to estimate the left-right difference of the line load distribution between rolls.

By the way, when the rolling mill is not a four-high rolling mill and the number of intermediate rolls is further increased, the contact area between the rolls is increased by one each time the number of intermediate rolls is increased.
If the thrust reaction force of the intermediate roll is measured, the unknowns that increase are the thrust force acting on the added contact area and the left-right difference of the linear load distribution. Both the axial force equilibrium condition expression and the moment equilibrium condition expression are added, and all the solutions can be obtained by simultaneous equations with other roll equations. Thus, even in the case of a rolling mill having four or more stages, at least by measuring the thrust reaction force acting on all rolls other than the reinforcing rolls,
It is possible to accurately determine the left-right difference in the linear load distribution that acts between all rolls in the kiss roll state, and accurately perform the zero adjustment of the reduction device and the deformation characteristics of the rolling mill, especially including the left-right asymmetry. Is possible.

[0023] Claims 2 and 3 disclose a plate rolling method for accurately performing the reduction leveling control during rolling based on the measured value of the rolling reaction force. For example,
In a normal four-high rolling mill, by measuring the roll axial thrust reaction force acting on the upper work roll and the reinforcing roll reaction force acting in the reduction direction at each reduction fulcrum position of the upper reinforcement roll, The unknown numbers of the forces acting on the upper reinforcing roll in the roll axial direction and the forces involved in the equilibrium condition formula of the moment are the following four.

T _B ^T : Thrust reaction force acting on the upper reinforcing roll chock T _WB ^T : Thrust force acting between the upper working roll and the reinforcing roll p ^df _WB ^T : Left and right of the linear load distribution between the upper working roll and the reinforcing roll Difference p ^df : Left-right difference in line load distribution between rolled material and work rolls The above-mentioned unknown does not include the thrust force acting between the rolled material and work rolls, but this is for the following reason.

The thrust reaction force between the rolls is due to the contact between the elastic bodies, and since the peripheral speeds of the rolls on the contact surfaces are almost the same in magnitude, the rolls that come into contact with each other due to the generation of a minute roll cross angle When there is a discrepancy in the roll axial component of the circumferential velocity vector of, the frictional force vector is in the direction along the roll axial direction. It is around 30%, which is almost equal to the friction coefficient. On the other hand, in the case of the thrust force acting between the rolled material and the work roll, the size itself does not match the speed of the rolled material and the work roll peripheral speed at a place other than the neutral point in the roll bite, The direction of the friction force vector does not match the roll axis direction even when a cross angle of about 1 ° is given as in the roll cross mill. Therefore, the roll axis direction component of the friction force vector in the roll bite is integrated. The thrust force obtained is around 5%, which is significantly smaller than the friction coefficient. From the above, in the case of an ordinary rolling mill that does not positively cross the work rolls, the cross angle that can be generated by the gap between the roll chock and the housing window is usually 0.1 ° or less, so the thrust between the rolled material and the work rolls is It turns out that power can be ignored.

The equations that can be used to obtain the above-mentioned four unknowns are the two equilibrium conditional expressions for the force in the roll axial direction of the work roll and the reinforcing roll and the two equilibrium conditional expressions for the moments of the work roll and the reinforcing roll. Is 4 in total,
It is possible to obtain all unknowns by solving these at the same time. If the above unknowns are obtained, the deformation of the upper roll system can be accurately calculated including the asymmetrical deformation.

Next, regarding the lower roll system, the rolled material
The left-right difference in the line load distribution between work rolls is required,
Since this is equal to and lower than the equilibrium condition of the force acting on the rolled material, the deformation of the lower roll system can be calculated including the left-right asymmetrical deformation if the left-right difference in the line load distribution between the lower work roll and the reinforcing roll is obtained. It will be possible. As a system of equations that can be used to solve this problem, two equilibrium conditional expressions for the force of the lower work roll and the lower reinforcing roll in the roll axial direction and an equilibrium conditional expression for the moments of the lower work roll and the lower reinforcing roll 2
There are a total of four, and for example, when neither the thrust reaction force of the lower roll system nor the reinforcing roll reaction force can be measured, the following five unknowns are related to the above equation system.

[0028] T_B ^B  : Anti thrust thrust acting on the lower reinforced roll chock
Power T_WB ^B  : Slur that acts between the lower work roll and the reinforcing roll
Strike force T_W ^B  : Thrust counter acting on lower work roll chock
Power p^df _WB ^B: Of the line load distribution between the lower work roll and the reinforcement roll
Left-right difference P^dfB  : Reinforcing roll at the lower fulcrum position
Le reaction force left-right difference Of the above unknowns, a well-managed rolling mill
Left-right difference in linear load distribution between work roll and reinforcement roll p^df _WB ^B
Is the difference p in the lateral load distribution between the rolled material and the work rolls. ^dfRatio to
In some cases, it is so small that it can be ignored. In this case, p
^df _WB ^BBy setting = 0, find all remaining unknowns
It becomes possible. If these conditions are not met
Also make at least one of the above unknowns known
Or find all remaining unknowns by actually measuring
It becomes possible. More preferably, the lower roll type
Even if the work roll thrust reaction force and reinforcement roll reaction force are left
If you can measure the right difference, the number of unknowns is less than the number of equations
Therefore, by obtaining the least squares solution, the accuracy is higher.
Calculation is possible. If the above unknowns are required, then lower
Accurate calculation of the deformation of the Le system including the asymmetrical deformation
It is possible to combine the roll deformation of the upper and lower rolls.
And calculated as a function of the reinforcing roll reaction force.
By superimposing deformations of the housing and rolling system,
By taking into account the gap between the upper and lower work rolls
It is possible to calculate the symmetry accurately, and
The resulting thickness wedge can be calculated. More than
After making preparations, the viewpoint of meandering or camber control
To achieve the target value of thickness wedge required by
The target value of the reduction position operation amount, especially the reduction leveling operation amount is
Calculation can be performed, and the lower pressure is calculated according to this target value.
Position control may be performed. In addition, in the above explanation
Even if the lower roll system is replaced, the present invention is exactly the same.
It goes without saying that it can be applied.

By the way, in the above description, as the asymmetry of the linear load distribution between the rolled material and the work roll, the case where only the left-right difference of the linear load is considered is considered, but the asymmetry of the roll load in the axial direction of the roll is considered. As the above, not only the above-mentioned asymmetry of the line load but also the phenomenon that the center of the rolled material is threaded at a position different from the mill center can be considered. The distance between the center of the rolled material and the mill center is called the off-center amount in the present invention, but the off-center amount is basically kept within a certain allowable amount by the side guide on the rolling mill entrance side. If the amount of off-center that can still occur is not negligible, it is preferable to estimate it from, for example, the value measured by the meandering sensor on the inlet side or the outlet side of the rolling mill. When such a sensor cannot be installed and an off-center amount that cannot be ignored can occur, for example, the following method is adopted.

From the equilibrium condition equation of the moment of the work roll, it is impossible to separate and extract two unknowns, the off-center amount and the left-right difference in the line load distribution between the rolled material and the work roll. Therefore, as described above, there are two cases where the off-center amount is zero and only the left-right difference of the line load is unknown, and when the left-right difference of the line load is zero and the off-center amount is unknown.
The target value of the reduction leveling operation amount is calculated for each of the two cases, and the target value of the actual reduction leveling operation amount is determined by, for example, the weighted average of the calculation results of the two. The weighting method will be adjusted as appropriate while observing the rolling conditions, but in general terms, a larger weight is placed on the side with a smaller reduction leveling operation amount, or a value with a smaller operation amount is adopted. However, it is practical to multiply this value by a tuning factor of 1.0 or less to obtain a control output.

In the above description, a four-high rolling mill has been described as an example. However, in the case of a rolling mill type with more intermediate rolls,
Each time the number of intermediate rolls increases, the contact area between the rolls increases by one place, and if the thrust reaction force of the intermediate rolls is measured,
The unknowns to be increased are the thrust force acting on the added contact area and the left-right difference of the linear load distribution. On the other hand, the available equations are the equilibrium condition equation of the roll axial force and the moment equilibrium condition equation. 2 will increase, and all solutions can be obtained by simultaneous equations with other roll equations. In this way, even in the case of a rolling mill having four or more stages, by measuring the thrust reaction force acting on at least all rolls other than the reinforcing rolls, the left-right difference in the linear load distribution acting between the rolling rolls can be determined. It is possible to obtain all unknowns including the above, and it is possible to calculate the optimum amount of reduction leveling operation as in the case of the four-high rolling mill.

Next, a case of a roll-cross type plate rolling machine represented by a pair cross mill will be described. As described above, in the roll cross rolling machine, the traveling direction of the rolled material and the direction of the peripheral velocity vector of the work roll generally do not coincide with each other, and the roll cross angle is about 1 °, which corresponds to this. As a result, a thrust force of about 5% of the rolling load is generated. Although this thrust force can be predicted with a certain degree of accuracy in advance, it is difficult to calculate an accurate value in advance because it depends on the surface properties of the roll as well as the temperature and deformation characteristics of the rolled material. Therefore, in order to carry out an accurate reduction leveling control, it is necessary to obtain the thrust force acting between the rolled material and the work roll as an unknown value. In this case, as in the case of the normal four-high rolling mill as described above, the number of equations will be insufficient if only the equation system relating to one of the upper and lower roll assemblies is used. It is necessary to use the equilibrium condition equation of the force in the roll axial direction and the equilibrium condition equation of the moment of all the upper and lower rolls. The number of equations in this case is
In the case of a four-high rolling mill, the number is eight, and the unknowns are the following eight.

T _B ^T : Thrust reaction force acting on the upper reinforcing roll chock T _WB ^T : Thrust force acting between the upper work roll and the reinforcing roll T _MW : Thrust force acting between the rolling material and the work roll T _WB ^B : thrust T _B ^B acting between the lower work roll-backup roll: a thrust reaction force acting on the lower reinforcing roll chocks p ^df _WB ^T: difference between right and left of the line load distribution between the upper work roll-backup rolls p ^df _WB ^B: lower Left-right difference in line load distribution between work roll and reinforcing roll p ^df : Left-right difference in line load distribution between rolled material and work roll By solving these unknowns by the above equation system, between rolled material and work roll and between rolls It is possible to obtain the left-right difference in the linear load distribution of the rolls.By using these calculated values, the roll deformation can be accurately obtained with respect to the left-right asymmetry of the roll gap, and the amount of the rolling leveling operation can be estimated. The standard value can be calculated.

[0034] Claim 4 discloses a rolling mill for carrying out the rolling method according to claims 1, 2, and 3 above. As already described, in order to carry out the rolling method according to claims 1, 2, and 3, the rolling mill is provided with a thrust axial reaction force measuring device acting on all rolls other than the reinforcing rolls. A reinforcing roll reaction force measuring device acting in a rolling direction should be provided at each rolling fulcrum position of the upper and lower reinforcing rolls. Here, the roll axial thrust reaction force measuring device is, for example, a device that detects a load acting on a keeper plate that restrains the axial movement of the roll via a roll chock or a stud bolt that restrains the keeper plate. In the case of a rolling mill having a roll axial shift function, this is a device that detects the load applied to the shift device, and is also installed inside the roll chock to directly detect the thrust force that acts on the outer race of the thrust bearing. It may be a device that does. Further, the measuring device of the reinforcing roll reaction force acting in the rolling direction at each rolling fulcrum position of the upper and lower reinforcing rolls is generally a load cell arranged at the rolling fulcrum position, for example, in a rolling mill having a hydraulic rolling device. In this case, a method of calculating from the measured value of the hydraulic pressure in the pressure reduction cylinder or in the pipe directly connected to the pressure reduction cylinder may be used. However, in this case, when the hydraulic pressure is rapidly changing the pressure reduction position, a large error will occur in the measured value, so measures should be taken such as temporarily holding the pressure reduction position when collecting pressure data. Is.

A fifth aspect of the invention discloses a more specific equipment form of a plate rolling machine for carrying out the rolling method of the first, second, and third aspects. Claims 1, 2, 3 as already described
In order to carry out the rolling method of No. 1, a roll axial thrust reaction force measuring device acting on rolls other than the reinforcing rolls disclosed in claim 4, and reinforcement acting in the rolling direction at each rolling fulcrum position of the upper and lower reinforcing rolls. In addition to the roll reaction force measuring device, enter at least these measured values to obtain the asymmetric distribution of the linear load acting between the rolls and the thrust force or the linear load distribution or the thrust force acting between the rolled material and the work roll. An arithmetic unit for calculating the asymmetry of is required. Here, it is essential for the asymmetrical deformation analysis of the roll system that must be finally performed for the rolling leveling setting control to be asymmetrical with respect to the mill center of the roll axial distribution of the load acting between the rolled material and the work rolls. sex,
Alternatively, in the case of the kiss roll state, there is an asymmetry with respect to the mill center of the roll axial distribution of the load acting between the upper and lower work rolls, and in the claim 5, these values are set to at least the roll shafts acting on rolls other than the reinforcing roll. An essential requirement is a computing device that computes the measured value of the directional thrust reaction force and the measured value of the reinforcing roll reaction force acting in the rolling direction at each rolling fulcrum position of the upper and lower reinforcing rolls as input data.

By the way, in the case of measuring the thrust reaction force acting on rolls other than the reinforcing roll, in the example of the above-mentioned measuring device, the measurement by the method of measuring the load applied to the outer race of the thrust bearing in the roll chock With the exception of the device, the external force that holds the roll chock in the roll axial direction will be measured. When the thrust reaction force measuring device of such a type is used, the roll balance force acting on each roll or the roll axial frictional force resulting from the roll bending force becomes a large disturbance of the thrust reaction force measurement value. That is, due to the resultant force of the thrust force acting on the body of each roll, the roll slightly moves in the direction of the thrust force, and this slight displacement causes the elasticity of the keeper plate or roll shift device that constrains the roll chock in the roll axial direction. Thrust reaction force is measured by inducing deformation, but when the roll chock is slightly displaced, it is possible to prevent the roll chock from displacing from the load applied part of the roll bending device or roll balance device that is in contact with the roll chock. Friction force acts. This frictional force itself is generally difficult to measure, and thus becomes a disturbance of the measured thrust force. Claims 6 to 1
No. 0 discloses a plate rolling machine that solves this problem.
In the following description and claims of the present invention, the roll balancing device and the roll balancing force are collectively referred to as a roll bending device and a roll bending force for the sake of simplicity. In claim 6, a roll bending device is provided for at least one set of rolls other than the reinforcing rolls, and at least one roll chock of the rolls having the roll bending device, for example, the roll chock of the upper work roll, is roll bending. A device for measuring the thrust reaction force acting on the roll chock for supporting the thrust reaction force, which has a structure in which it is separated into a roll chock that supports a radial load in the rolling direction such as a force and a roll chock that supports a thrust reaction force in the roll axial direction. Is provided. In this case, the radial load supporting roll chock can have a structure that does not receive thrust force, for example, by fitting the inner race of the bearing and the roll shaft with a clearance fit, or by using a cylindrical roller bearing that does not employ the inner race. With such a structure, even when the roll bending force is applied, a slight axial displacement of the upper work roll is transmitted only to the thrust reaction force supporting chock. Is small enough to be ignored. on the other hand,
Like the upper work roll, the lower work roll has a structure in which the chocks are not separated, and when thrust force acts on the lower work roll, a frictional force corresponding to the roll bending force acts between the lower work roll and the upper work roll chock. Since the upper work roll chock does not support the thrust force, the upper work roll chock is slightly displaced together with the lower work roll chock in the direction in which the thrust force acts, and the reaction force of the thrust force acting on the lower work roll is also accurately transmitted through the lower work roll chock. Can be detected.

A seventh aspect of the present invention discloses a sheet rolling machine provided with a mechanism capable of applying a vibration component having a frequency of 5 Hz or more to the roll bending force. By superposing the vibration component in addition to the predetermined force on the roll bending force in this way, the frictional force between the load portion of the roll bending force and the roll chock is significantly reduced, and the measurement accuracy of the thrust force measurement value is improved. Greatly improved. This is because when the thrust force acts on the work roll as described above, the thrust force is measured by slightly displacing the work roll in the roll axial direction, but when the roll bending force vibrates, This is because the work roll is displaced in the roll axial direction and transmits the thrust force at the moment when the roll bending force becomes the smallest. The frequency of the added vibration component is 5H
If it is less than z, the deflection of the work roll itself changes greatly in response to the vibration of the roll bending force, which adversely affects the plate crown and shape and reduces the frictional force reduction effect in the roll axial direction. The component is 5
Hz or higher, preferably 10 Hz or higher is suitable.

The eighth aspect of the present invention discloses a plate rolling machine in which a slide bearing mechanism having a degree of freedom in the roll axial direction is provided between the load applying part of the roll bending device and the roll chock. Due to the presence of such a slide bearing mechanism, the frictional force of the roll bending force between the load-bearing portion and the roll chock is significantly alleviated, and the measurement accuracy of the thrust reaction force measurement value is greatly improved.

In a ninth aspect of the present invention, at least a part of the roll bending device is covered with a thin skin whose elastic deformation resistance against out-of-plane deformation is 5% or less of the maximum value of the roll bending force, between the load application part and the roll chock. Disclosed is a plate rolling machine in which a load transmitting portion having a configuration in which a liquid is sealed in a closed space is inserted. This load transmitting part is narrowed between the load applying part of the roll bending device and the roll chock, but the thin skin has sufficient strength so that the liquid film inside will not be broken, and the thin skin Resistance to out-of-plane deformation is 5% of maximum roll bending force
Since it is as follows, it is possible to sufficiently reduce the apparent frictional force acting from the load applying portion of the roll bending device with respect to the minute displacement of the roll chock in the roll axial direction. When such a load transmitting part is not provided, the load applying part of the roll bending device and the roll chock are in solid contact with each other, so that the friction coefficient is usually 30%.
Before and after. On the other hand, when this load transmission part is inserted, the shear deformation resistance of the liquid film inside is almost negligible, so the apparent friction force is less than 5% of the maximum value of the roll bending force, and as a result, the thrust force is reduced. The measurement accuracy of the reaction force measurement value is significantly improved.

In a tenth aspect, when a roll other than the reinforcing roll has a roll shift mechanism, a plate rolling machine is provided which is provided with a function of giving the shift mechanism a minute shift oscillation with an amplitude of 1 mm or more and a period of 30 seconds or less. is doing. In this way, by giving a swing function to the roll shift mechanism and actually swinging the roll shift mechanism, the direction of the frictional force acting between the load-bearing portion of the roll bending device and the roll chock is reversed, so that the measured shift force, that is, Accurate thrust reaction force can be measured by taking the average value of the thrust reaction force. Here, the amplitude of 1 mm or more is 1 mm.
If the amplitude is less than, the swing is absorbed by the play of the roll chock and the bearing in the roll axial direction and the deformation of the load applied part of the roll bending device in the roll axial direction, and the direction of the frictional force does not reverse. Is. Regarding the oscillation cycle, only one point of thrust reaction force data can be obtained by taking the average value in this cycle, and the reduction position control corresponding to this can be performed. Therefore, the reduction position meaningful for the rolling operation can be achieved. The cycle time for implementing the control is determined to be 30 seconds or less.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. In the following, for simplification, all four-high rolling mills will be described as an example, but as described above, the present invention similarly applies to a five-high rolling mill or a six-high rolling mill or more in which an intermediate roll is further added. Applicable.

FIG. 1 is a diagram showing an algorithm of a preferred embodiment of the zero reduction adjustment of a four-high rolling mill in the strip rolling method according to claim 1 of the present invention. The reduction zero point adjustment is performed after the rolls are recombined, and usually, the kiss roll tightening is performed until the reaction force of the reinforcing roll reaches a predetermined zero adjustment load. At this time, the reduction leveling is also adjusted so that the left and right reinforcing roll reaction forces are equalized, and then the reduction position is temporarily reset to zero. As the reaction force of the reinforcing rolls, the reaction force of the upper or lower reinforcing rolls may be used alone, or for example, the average value of the reaction forces of the upper and lower reinforcing rolls may be used. Figure 1
In this condition, the vertical and horizontal reinforcing roll reaction forces and the thrust reaction forces of the upper and lower work rolls are measured in that state, and the equilibrium condition formula of the force in the roll axial direction acting on the reinforcing roll and the work roll and the equilibrium condition of the moment From the equation, the thrust reaction force of the reinforcing rolls, the thrust force acting between the rolls, and the lateral difference of the linear load distribution are calculated. A specific example of this calculation method is shown below.

FIG. 2 schematically shows the force acting on each roll in the axial direction of the roll and the force related to the moment of each roll. Here, regarding the force in the vertical direction, only the left-right asymmetric component related to the moment of the roll is considered, and in order to simplify the explanation further, the left-right asymmetric component of the linear load distribution acting between the rolls is measured in the width direction. Coordinate 1
Only the following formula components are considered. When actually applied, depending on the deformation characteristics of the rolling mill, 3 in the width direction coordinate
It is also possible to employ an asymmetrical component in which the following or more components are superposed. Of the force components shown in FIG. 2, the following four are available as measured values.

[0044] ^P dfT: top back-up roll pressure rolls reaction force left-right difference in the fulcrum position ^P dfB: lower reinforcing roll pressure fulcrum rolls reaction force left-right difference in the position ^T _W T: thrust reaction force acting on the upper work roll T _W ^B : Thrust reaction force acting on the lower work roll In addition, unknown variables are the following eight variables.

T _B ^T : Thrust reaction force acting on upper reinforcing roll chock T _WB ^T : Thrust force acting between upper work roll and reinforcing roll T _WW : Thrust force acting between upper and lower work rolls T _WB ^B : Lower work thrust T _B ^B acting between the rolls - rolls: thrust counterforces acting on the lower reinforcing roll chocks p ^df _WB ^T: top work roll - reinforcing laterality p ^df _WB line load distribution between rolls ^B: lower work rolls ^{-Left and} right difference in linear load distribution between reinforcing rolls p ^df _WW : Left and right difference in linear load distribution between upper and lower work rolls Note that the position of the thrust reaction force acting on the reinforcing roll in Fig. 2 and the axial position of the reinforcing roll Distance to h _B ^T and h
_B ^B, for example, it is assumed in advance identified by observing the rolls change in reaction force giving a known thrust force. The position of the reaction point of the thrust force of the work roll acts on the work roll shaft center position in FIG. 2, but it may deviate from the roll shaft center position depending on the type of work roll chock and the support mechanism. In such a case, the thrust reaction force position should be identified by a method such as applying a known thrust force to the work roll.

From FIG. 2, the upper reinforcing roll, the upper working roll,
The equilibrium condition formulas for the forces of the lower work roll and the lower reinforcing roll in the roll axial direction are as follows. _{^{-T WB T = T B T (}} 1) T WB T -T WW = T W T (2) T WW -T WB B = T W B (3) T WB B = T B B (4) The upper The equilibrium condition equation of the moments of the reinforcing roll, the upper work roll, the lower work roll, and the lower reinforcing roll is given by the following formula.

[0047] _{^{T WB T · (D B T}} / 2 + h B T) + p df WB T (l WB T) 2/12 = P df T · a B T / 2 (5) T WB T · D W T / 2 + T ^{_{WW · D W T / 2-}} p df WB T (l WB T) 2/12 + p df WW (l WW) 2/12 = 0 (6) T WB B · D W B / 2 + T WW · D W B / _{^{2 + p df WB B (l}} WB B) 2/12 -p df WW (l WW) 2/12 = 0 (7) T WB B · (D B B / 2 + h B B) -p df WB B (l WB B _{^{) 2/12 = -P df B}} · a B B / 2 (8) _{^{wherein, D B T, D B B}} , D W T, D W B , respectively upper and lower rolls diameter, there upper and lower work rolls diameter , L _WB
^T, l _WW, l _WB ^B, respectively on the rolls - the work rolls contact area, the upper and lower work rolls contact area, the lower back-up rolls -
It is the length in the roll axial direction of the work roll contact area. In addition,
In equations (5) and (8), using equations (1) and (4), T _B
^T and T _B ^B are erased. By solving the above eight equations simultaneously, all the above eight unknowns can be obtained.

In the next step shown in FIG. 1, the left and right difference of the roll deformation amount in the reduction zero adjustment state is calculated using the above calculation result, and the left and right difference is converted into the reduction fulcrum position to correct the reduction zero point position. Calculate the quantity. The left-right difference of the roll deformation amount is mainly caused by the left-right asymmetric component of the linear load distribution acting between the rolls, and the main cause thereof is the left-right difference of the roll flat deformation amount, which is the p ^df _WB ^T , which has already been obtained. p ^df _WB ^B ,
It can be calculated immediately from p ^df _WW . By extrapolating the left-right difference of the total amount of flat deformation at the roll body end position obtained from this calculation result to the rolling fulcrum position of the reinforcing roll, the correction amount of the rolling zero point position can be calculated. When extrapolating the flat deformation amount, it is preferable to consider the asymmetry of roll deflection and the asymmetry of roll neck deformation.

The thrust force between the rolls generated during zero adjustment is
Since it is unlikely to occur in the same manner during rolling, it is preferable that the rolling zero point that serves as the reference of the rolling position is based on the state where the thrust force between the rolls is zero. For this reason, it is desired to set the ideal state where the asymmetric load due to the above-mentioned thrust force between the rolls does not occur as the true rolling zero point. That is, the position where the rolling reduction position is moved in the direction in which the amount of lateral asymmetry of the roll deformation amount calculated above is eliminated becomes the true zero point. By setting the rolling position zero point in this way, it is possible to perform an accurate rolling setting in consideration of the laterally asymmetric load and deformation that occur during actual rolling.

For the purpose of obtaining the same effect, the roll zero point is not corrected as shown in FIG. 1, but the roll asymmetric deformation amount at the time of zero adjustment is stored in advance. However, it is also possible to deal with it by a method that always corrects the actual reduction setting. Even with such a method, it is clear that the zero point is substantially corrected at the time of the calculation of the rolling reduction, which is another embodiment of the present invention. Also, here, the explanation was given focusing only on the left-right asymmetrical deformation. It is also important from the viewpoint of plate thickness accuracy to correct the reduction zero point position including the symmetrical component. However, also in this case, it is possible to memorize the actual zero-adjustment load and always use the actual zero-adjustment load as a reference when calculating the reduction setting. By the way, it is general that zero-adjustment load is basically aimed at a left-right difference of zero, but when a significant left-right difference occurs in the actual zero-adjustment load, this left-right difference is also included as described above. If the actual zero adjustment load including this left-right difference is always used as a reference when calculating the reduction setting, it is possible to handle it, but if the actual load of zero adjustment load cannot be used when calculating the reduction setting. In addition to the left-right difference in the amount of roll deformation as shown in FIG. 1, it is necessary to correct the left-right difference in the amount of deformation of the housing / compression system due to the left-right difference in the reaction force of the reinforcing roll.

FIG. 3 shows a data collection procedure for obtaining the deformation characteristics of a four-high rolling mill in the strip rolling method according to claim 1 of the present invention. The deformation characteristic referred to herein is so-called mill stretch, and means a change in the gap between the upper and lower work rolls that occurs as a result of elastic deformation of the rolling mill when a rolling load is applied. When grasping this mill stretch, the deformation of the roll system can be obtained with high accuracy by the existing method, but the deformation characteristics of the housing and the rolling system other than the roll system are theoretical because they include many elastic contact surfaces. It is generally difficult to know exactly. Therefore, in Japanese Examined Patent Publication No. 4-74084, a kiss roll tightening test is performed in advance before rolling work, and the deformation amount of the roll system is calculated and separated from the deformation amount for each tightening load at that time,
A method for separating the deformation characteristics of the housing / roll-down system is disclosed, and Japanese Patent Laid-Open No. 6182418 discloses a method for independently separating the deformation characteristics of the left and right housing / roll-down systems. However, in the method of JP-A-6-182418, since the influence of the thrust force acting between the rolls is not considered at all, sufficient accuracy can be obtained when the thrust force between the rolls reaches a certain value or more. There was a problem that can not be. Claim 1 of the present invention is a technique capable of solving this problem as well, and as shown in FIG. 3, when carrying out a kiss roll tightening test, the vertical and horizontal reinforcing roll reaction forces and the vertical reaction roll thrust reaction forces are measured. To do. Generally, the deformation characteristics of the housing and the rolling system change depending on the rolling load.
In the kiss roll tightening test shown in (1), data is collected at multiple rolling positions and tightening load levels. It is better that the number of the rolling position levels is larger, but practical accuracy can be obtained if data of about 10 to 20 points can be collected by an ordinary rolling mill. However, at this time, so-called mil hysteresis often occurs, which causes a difference in tightening load between the tightening direction and the releasing direction of the reduction device, and in such a case, at least the tightening direction and the opening direction are at least changed. It is preferable to collect data for one reciprocating operation and perform an operation such as averaging the measured data of both.

FIG. 4 shows an algorithm for independently calculating the left and right deformation characteristics of the housing / rolling down system using the data collected according to the procedure of FIG.
First, the measured values of the vertical and horizontal reinforcing roll reaction forces and the thrust reaction forces of the upper and lower work rolls for each rolling position condition are extracted. Next, in exactly the same manner as in the case of the above-mentioned reduction zero point adjustment, the thrust reaction force of the upper and lower reinforcing rolls, The left-right difference between the thrust force acting between rolls and the linear load distribution is calculated. If the load distribution between these rolls is obtained, the flexural deformation and flat deformation of the reinforcing roll and the work roll can be calculated including the left-right difference by the method disclosed in Japanese Patent Publication No. 4-74084. It is possible to calculate the displacement that occurs at the rolling fulcrum position of the reinforcing roll as a result of these deformations. Finally, since the deformation amount of the entire mill is evaluated by the change in the rolling position, the deformation amount of the roll system at the rolling fulcrum position is subtracted from this, and the deformation characteristics of the housing and the rolling system are independently calculated. By performing the roll deformation calculation based on the accurate identification of the thrust force between the rolls in this manner, it becomes possible to accurately grasp the deformation characteristics of the housing / rolling down system including the left-right difference. When applying this method to a rolling mill where the thrust force between rolls is considerably large, there is a large difference in the reaction force between the upper and lower reinforcing rolls, and the difference in the reaction force between the upper and lower reinforcing rolls affects the deformation characteristics of the housing and the rolling system. However, in such a case, various differences between the upper and lower roll reaction forces may be generated by means such as giving a minute cross angle between the rolls, and the housing / roll-down system may be subjected to the above procedure. The deformation characteristics of the rolling mill can be accurately identified by identifying the deformation characteristics of the rolling stock and arranging them as a function of the vertical reaction force difference.

FIG. 5 shows an algorithm of a preferred embodiment of the rolling position control of a pair cross type four-high rolling mill in the strip rolling method according to claims 2 and 3 of the present invention. First, the reinforcing roll reaction force acting on the rolling fulcrum position of the upper and lower reinforcing rolls during rolling and the thrust reaction force of the upper and lower work rolls are measured. Next, the thrust reaction force of the reinforcing roll, the thrust force acting between the reinforcing roll and the working roll, and the linear load distribution are calculated from the equilibrium condition formula of the force acting on the reinforcing roll and the work roll axial direction and the equilibrium condition formula of the moment. And the lateral difference between the thrust force acting between the work roll and the rolled material and the linear load distribution are calculated. In this example, it is assumed that the off-center amount of the rolled material is known from the value measured by the sensor or the like, and therefore the above-mentioned calculation procedure can be executed by the same method as in the case of the reduction zero point adjustment of FIG. Using the load distributions between the rolls and between the rolled material and the work rolls obtained as a result of this calculation, the flexural deformation and flat deformation of the reinforcing rolls and work rolls are calculated including the left-right difference, and as a function of the reinforcing roll reaction force. Calculate the deformation of the housing / rolling system and calculate the current thickness distribution. At this time, regarding the deformation characteristics of the housing / rolling-down system, it is preferable to use those identified by the method shown in FIG. Then, the target value of the rolling position manipulated variable for achieving the target value is calculated from the plate thickness distribution predetermined as a target for rolling operation and the estimated value of the calculated current thickness distribution result at the present time. Then, the reduction position control is performed based on this target value. By using this method, it is possible to accurately and without delay grasp the asymmetry of the sheet thickness distribution that occurs immediately below the roll bite, and especially in the hot strip finishing rolling where swift and appropriate rolling position control is required. A great effect can be obtained on the strip stability during strip passing and tail end striping. It should be noted that information obtained from the rolling mill alone as described above is used as a meandering sensor, a looper load cell, or other detection device on the rolling mill entrance / exit side, and in the case of tandem rolling, another rolling mill on the upstream side or the downstream side. It is also effective to perform comprehensive control by combining information from the above. FIG. 5 shows a control method for the pair cross rolling mill in consideration of the thrust force acting between the work roll and the rolled material. However, in the case of a normal four-high rolling mill which is not the pair cross rolling mill, as already described. Since the thrust force between the work roll and the rolled material is so small that it can be ignored, the control similar to that shown in FIG. 5 can be carried out by using only the information on one of the upper and lower roll systems, and it is possible to use all the measured values of the upper and lower sides. If it is possible, the unknown number will be reduced by one. Therefore, it is possible to obtain a more accurate solution by obtaining the least squares solution using all of the force balance condition equations for the roll axis direction and the moment balance condition equations. Become.

FIG. 6 shows a plate rolling machine according to claim 4 of the present invention.
1 illustrates a preferred embodiment of a four-high rolling mill having a roll shift mechanism. Work rolls 1a, 1b, reinforcing rolls 2a, 2
In the four-high rolling mill consisting of b, reinforcing roll reaction force measuring devices, that is, load cells 6a, 6b, 6c and 6d are arranged at the left and right rolling fulcrum positions of the upper and lower reinforcing rolls. Further, the work rolls 1a and 1b are connected to the work roll axial shift devices 8a and 8b, and between the chocks 4b and 4d supporting the thrust reaction force acting on the work rolls and the work roll shift devices 8a and 8b. Is a load cell 7 for measuring the thrust reaction force acting on the work roll.
a and 7b are provided. By using the four-high rolling mill having such a structure, the reaction force of the upper and lower / left and right reinforcing rolls and all rolls other than the reinforcing rolls, that is, FIG.
In the case of the above example, the thrust reaction force acting on the upper and lower work rolls can be measured, and the plate rolling method according to claims 1 to 3 of the present invention can be carried out. When the actuator of the work roll shift device is a hydraulic cylinder, a work roll thrust reaction force measuring device is used instead of the load cells 7a and 7b by a pressure measuring device that measures the pressure in the hydraulic cylinder or in the hydraulic pipe directly connected to the hydraulic cylinder. You may substitute. If the work roll shift device is not provided, the load acting on the keeper plate that constrains the thrust reaction force measuring device and the work roll chock in the roll axial direction provided in the roll chock of the work roll is measured as described above. A device or the like may be adopted.

FIG. 7 shows a plate rolling machine according to claim 5 of the present invention.
A preferred embodiment in the case of a four-high rolling mill having a roll shift mechanism is shown. In FIG. 7, in addition to the plate rolling machine of FIG.
At least the measured values from the load cells 6a to 6d for measuring the vertical and horizontal reinforcing roll reaction forces and the measured values from the load cells 7a and 7b for measuring the thrust reaction force of the upper and lower work rolls are used as input data, and at least between the rolled material and the work rolls. It has an arithmetic unit 10 which uses as output data 11 the asymmetry of the load axial distribution of the load acting on the mill center with respect to the mill center or the asymmetry of the load acting between the upper and lower work rolls with respect to the mill center. . By using the plate rolling machine having such a configuration, the present invention claims 1 to 3.
The plate rolling method of 3 can be implemented. A process computer is usually used as the arithmetic unit 10, but the arithmetic unit does not need to be an independent computer, and among computers having more comprehensive functions,
If there is a part of the program that performs the above functions,
It is assumed that a part of the program and the computer are regarded as the arithmetic unit 10.

FIG. 8 shows a plate rolling machine according to claim 6 of the present invention.
A preferred embodiment in the case of a four-high rolling mill having a roll shift mechanism is shown. In the plate rolling machine of FIG. 8, the work roll chocks 4a, 4b, 4c, 4d have a structure that supports only radial loads acting in the vertical direction or the rolling direction, and the thrust force in the roll axial direction is a dedicated thrust force. It has a structure in which it is supported by reaction force supporting chocks 13a and 13b. In general, the work roll chock is loaded with a roll bending force, and a frictional force in the roll axial direction acts between the load application parts 12a, 12b of the roll bending device and the work roll chock 4a, 4b, which causes thrust reaction. It becomes a disturbance to the thrust reaction force measurement value by the force measuring load cells 7a and 7b. However, as in the embodiment of FIG. 8, the work roll chock that supports the roll bending force has a structure that does not receive the thrust force, so that the frictional force acting in the roll axial direction can be minimized. Therefore, the accuracy of the thrust reaction force measurement will be dramatically improved. By the way, when the work roll shift mechanism is provided as shown in FIG.
Since the work roll shift directions are usually opposite, it is preferable that the radial load supporting chocks 4a, 4b, 4c, 4d be constrained by an unillustrated keeper plate or the like so as not to move in the axial direction.

Further, in FIG. 8, the thrust reaction force measuring load cells 7a and 7b are provided in the work roll shift devices 8a and 8b, but in the case of a rolling mill having no work roll shift device, the thrust reaction force supporting devices are used. Chocks 13a, 13
b is constrained in the roll axial direction by a keeper plate or the like via the thrust reaction force measuring load cells 7a and 7b. further,
In the case of a rolling mill that does not have a work roll shift device, the amount of movement in the roll axial direction is extremely small, so as already mentioned, only one of the upper and lower work roll chock is the radial load supporting chock and thrust reaction force supporting chock. Similar effects can be obtained by simply separating into.

FIG. 9 shows a plate rolling machine according to claim 7 of the present invention.
A preferred embodiment in the case of a four-high rolling mill having a roll shift mechanism is shown. The plate rolling machine of FIG. 9 has a work roll bending device of a hydraulic servo system, and has a function of superposing a vibration component having a frequency of 10 Hz on a predetermined work roll bending force. As described above, when such a plate rolling machine is used, when the thrust reaction force is measured, the accuracy of measuring the thrust reaction force can be improved by superposing the vibration component on the predetermined roll bending force.

FIG. 10 shows a preferred embodiment of a four-high rolling mill in the strip rolling mill according to claim 8 of the present invention. In the embodiment shown in FIG. 10, the load applying unit 12 of the roll bending apparatus is used.
Slide bearing mechanisms 15a and 15b having a degree of freedom in the roll axial direction are provided between a and 12b and the upper work roll chocks 4a and 4b. With such a configuration, even when a roll bending force acts, the load application part 12 a of the roll bending apparatus, 12
The frictional force in the roll axial direction acting between b and the work roll chock becomes negligibly small, and the work roll thrust reaction force can be accurately measured. In addition, the slide bearing mechanism has a limited operating range,
Since the frictional force reduction effect in the direction exceeding the operation limit is lost at that operation limit position, for example, a mechanism such as a spring mechanism that returns to the center position of the operation range when there is no load is provided, and kiss roll tightening is performed regularly. Then, it is preferable to perform the operation of releasing the roll bending force and returning the slide bearing mechanism to the center position of the operation range. However, the restoring force of this spring mechanism must be sufficiently weaker than the thrust force acting on the roll and stronger than the operating resistance of the slide bearing under no load. See also FIG.
0, slide bearing mechanism 15 on the upper chock side
a, 15b, roll bending device 1 on the lower chock side
Although 2a and 12b are provided, they may be replaced with each other, and the slide bearing mechanism may be provided on the load applying portion side of the roll bending device. Furthermore, FIG.
Although the plate rolling machine of No. 1 does not have the function of shifting the work roll in the axial direction, the slide bearing mechanism can be applied even if the work roll shift mechanism is provided. However,
When the work roll shift device is used to change the work roll position, the slide bearing mechanism may reach the operation limit position. In such a case, it is preferable to return the slide bearing mechanism to the center position of the operating range by performing an operation such as releasing the work roll bending force as described above.

FIG. 11 shows a preferred embodiment of the strip rolling mill according to claim 9 of the present invention in the case of a four-high rolling mill. Figure 1
1 is a work roll bending device 12a, 12b of the work roll bending work roll chock 4 abutting against the load application part
Between c and 4d, the liquid is enclosed in a closed space at least part of which is covered by a thin skin whose elastic deformation resistance against out-of-plane deformation is 5% or less of the maximum value of the roll bending force,
The load transfer portions 16a, 1a configured so that the liquid film is not broken even with respect to the maximum value of the roll bending force.
6b. A specific example of this load transmitting portion is shown in FIG. 12 or FIG. In the example of FIG. 12, the lower work roll 4
A load transmission unit 16a is provided above the c, and a liquid is enclosed in a space surrounded by the roll chock 4c, the metal plate 19, and the thin outer skin 17. As the material of the thin-walled skin 17, for example, a high-strength polymer material or a composite material in which a carbon fiber woven fabric is lined to prevent liquid outflow can be used. By adopting the outer skin having sufficient strength even with a thin wall in this way, even if the load applying portion 12a for the roll bending force and the work roll chock 4c are slightly displaced relative to each other in the roll axial direction, the load transmitting portion 16a The shear deformation resistance generated, that is, the apparent friction coefficient, can be made so small that it can be almost ignored. As the liquid inside, a liquid having a rust preventive effect is preferable, and, for example, oil or grease may be used. FIG.
Shows another form of the load transmission portion 16a. Figure 1
In the load transmitting portion 16a of the third example, the liquid 18 has a thin outer skin 17
The structure is enclosed in a bag-shaped closed space composed of. With such a structure, it is possible to easily replace the load transmission portion with respect to deterioration over time. By the way, the plate rolling mill of FIG. 11 does not have a function of shifting the work rolls in the axial direction. However, even if the work roll shift mechanism is provided, the load transmission unit of the type shown in FIG. 12 can be used. However, in this case,
It is preferable to implement the mechanism and operation for returning the movement limit position to the center as in the slide bearing mechanism described in 0. In FIG. 11, the roll bending devices 12a and 12b are provided on the upper work roll chock side and the load transmission parts 16a and 16b are provided on the lower work roll chock side. Can be installed on the load side of the roll bending device.

FIG. 14 shows a preferred embodiment of the sheet rolling mill according to claim 10 of the present invention in the case of a four-high rolling mill. Figure 1
In the fourth embodiment, work roll shift devices 8a and 8b for shifting the work rolls in the roll axial direction are provided, and work roll chocks 4b and 4d that support the thrust reaction force acting on the work rolls and the work roll shifts. Load cell 7 for measuring thrust reaction force between devices 8a and 8b
a and 7b are installed. The work roll shift device 8
In addition to the movement to a predetermined work roll position, a and 8b are provided with a function of giving a minute shift swing 23a, 23b having an amplitude of 1 mm or more and a period of 30 seconds or less in the roll axis direction. Such a function is, for example, in the case of a work roll shifter of a hydraulic servo system, a function generator superimposes a signal corresponding to a predetermined swing on an input signal which gives a target roll shift position in a controller of the shifter. It can be realized by doing. When collecting work roll thrust reaction force data using such a work roll shift device, it is preferable to give a minute shift oscillation of a sine wave pattern at ± 3 mm and a cycle of about 5 seconds to generate thrust reaction for at least one cycle. The force measurement values are averaged to obtain a thrust reaction force value when the rolling method according to claims 1 to 3 is carried out. By doing so, the direction of the frictional force acting between the load application parts 12a, 12b of the work roll bending device and the work roll chocks 4a, 4b is reversed, the thrust reaction force is measured, and this is averaged. This makes it possible to eliminate the influence of the frictional force. It should be noted that an optimum value for this amplitude should be selected according to the mechanical accuracy of the work roll shifter. For example, when the mechanical play is larger than 6 mm, a swing of at least ± 4 mm is applied. Otherwise, the work roll cannot be effectively swung to reverse the frictional force between the load-bearing part of the roll bending device and the work roll chock. Further, if this amplitude is too large, it will affect the rolling operation itself, so it is preferable to employ the minimum amplitude at which the frictional force is reversed. The oscillation frequency is preferably short from the viewpoint of the thrust reaction force measurement cycle, but if it is too short, the peak value of the thrust reaction force becomes too large, affecting the rolling operation or shifting work rolls. Since the load limit of the device may be exceeded, in such a case, it is preferable to lengthen the oscillation period with the required measurement period of the thrust reaction force as the upper limit.

[0062]

As described above, according to the present invention, the rolling leveling setting / control of the rolling mill, which has conventionally relied on the operator, can be automated, and more accurate and appropriate rolling leveling setting / control than ever before can be performed. Since it is possible to significantly reduce the frequency of occurrence of meandering and passing problems in rolling, and also to significantly reduce the camber and strip thickness wedge of rolled material, it is possible to achieve cost reduction and quality improvement at the same time for rolling. It will be possible.

[Brief description of drawings]

FIG. 1 is a diagram showing an algorithm of a preferred embodiment of a reduction zero point adjusting method in the case of a four-high rolling mill according to the strip rolling method of claim 1 of the present invention.

FIG. 2 is a schematic diagram showing a left-right asymmetric component of a force in a roll axial direction and a force in a vertical direction which act on each roll of a four-high rolling mill.

FIG. 3 is a diagram showing an example of a procedure of actual machine data measurement for identifying deformation characteristics in the case of a four-high rolling mill according to the strip rolling method of claim 1 of the present invention.

FIG. 4 is a diagram showing an algorithm of a preferred embodiment of deformation characteristic calculation in the case of a four-high rolling mill in the strip rolling method according to claim 1 of the present invention.

FIG. 5 is a diagram showing an algorithm of a preferred embodiment of the rolling position control in the case of a pair cross type four-high rolling mill according to the strip rolling method of claims 2 and 3 of the present invention.

FIG. 6 is a view showing a preferred embodiment of a sheet rolling mill according to claim 4 of the present invention in the case of a four-high rolling mill having a roll shift mechanism.

FIG. 7 is a view showing a preferred embodiment of a sheet rolling mill according to claim 5 of the present invention in the case of a four-high rolling mill having a roll shift mechanism.

FIG. 8 is a diagram showing a preferred embodiment of a sheet rolling mill according to claim 6 of the present invention in the case of a four-high rolling mill having a roll shift mechanism.

FIG. 9 is a view showing a preferred embodiment of a sheet rolling mill according to claim 7 of the present invention, which is a four-high rolling mill having a roll shift mechanism.

FIG. 10 is a diagram showing a preferred embodiment in the case of a four-high rolling mill according to claim 8 of the present invention.

FIG. 11 is a diagram showing a preferred embodiment in the case of a four-high rolling mill according to claim 9 of the present invention.

FIG. 12 is a diagram showing a specific example of a load transmission unit used in the plate rolling mill according to claim 9 of the present invention.

FIG. 13 is a diagram showing another specific example of the load transmitting portion used in the plate rolling mill according to claim 9 of the present invention.

FIG. 14 is a view showing a preferred embodiment in the case of a four-high rolling mill according to claim 10 of the present invention.

[Explanation of symbols]

1a, 1b ... Work rolls 2a, 2b ... Reinforcement roll 3 ... Rolled materials 4a, 4b, 4c, 4d ... Work roll chocks 5a, 5b, 5c, 5d ... Reinforcement roll chocks 6a, 6b, 6c, 6d ... Reinforcement roll reaction force measurement Load cells 7a, 7b ... Load cells for thrust reaction force measurement 8a, 8b ... Work roll shift devices 9a, 9b ... Rolling down device 10 ... Calculation device 11 ... Outputs 12a, 12b of work device 10 ... Loads of work roll bending device
Load portion) 13a, 13b ... Thrust reaction force supporting work roll chocks 14a, 14b ... Keeper plates 15a, 15b ... Slide bearing mechanisms 16a, 16b ... Load transmission portion 17 containing liquid ... Thin outer skin 18 ... Liquid 19a, 19b, 19c , 19d ... Reinforcement roll reaction force 20 ... Line load distribution between upper work roll and reinforcement roll 21 ... Line load distribution between upper and lower work rolls 22 ... Line load distribution between lower work roll and reinforcement rolls 23a, 23b ... Minute shift swing direction

Front page continuation (51) Int.Cl. ⁷ Identification symbol FI B21B 37/00 BBH B21B 37/00 BBH (72) Inventor Taku Kawaguchi 5-3 Tokai-cho, Tokai-shi, Aichi Pref. Nippon Steel Co., Ltd. Nagoya Steel In-house (72) Inventor Koji Kawakami 5-3 Tokai-cho, Tokai-shi, Aichi Nippon Steel Corporation Nagoya Works (58) Fields investigated (Int.Cl. ⁷ , DB name) B21B 37/00-37 / 78 B21B 13/14 B21B 29/00 B21B 31/02

Claims (10)

(57) [Claims] 1. A rolling method using a multi-high rolling mill having four or more rolling steps, and in a kiss roll tightened state, measured values of roll axial thrust reaction force acting on at least all rolls other than the reinforcing rolls and upper and lower reinforcing rolls. From the measured value of the reinforcing roll reaction force acting in the rolling direction at each rolling fulcrum position, one or both of the zero point of the rolling device and the deformation characteristic of the rolling mill is obtained, and based on this, the rolling reduction at the time of rolling is performed. A sheet rolling method characterized by performing position setting and / or control. 2. A rolling method using a multi-high rolling mill having four or more rolling steps.
In the upper or lower roll assembly or both upper and lower roll assemblies, the measured values of the roll axial thrust reaction force that acts on all rolls other than the reinforcing rolls and the reinforcing rolls that act in the rolling down direction at each rolling fulcrum position. A plate rolling method comprising: calculating a target value of a rolling position manipulated variable of a rolling mill from a measured value of a reaction force, and performing a rolling position control based on the target value of the rolling position manipulated variable. 3. A rolling method using a multi-high rolling mill having four or more rolling steps.
In the upper or lower roll assembly or both upper and lower roll assemblies, the measured values of the roll axial thrust reaction force that acts on all rolls other than the reinforcing rolls and the reinforcing rolls that act in the rolling down direction at each rolling fulcrum position. From the measured value of the reaction force, at least the asymmetry with respect to the mill center of the roll axial distribution of the load acting between the rolled material and the work rolls is calculated, and based on the calculation result, the target of the rolling position operation amount of the rolling mill is calculated. A sheet rolling method, wherein a value is calculated, and the rolling position control is performed based on the target value of the rolling position operation amount. 4. A multi-stage plate rolling machine having four or more stages, which measures a roll axial thrust reaction force acting on all rolls other than the reinforcing rolls, and acts in the rolling direction at each rolling fulcrum position of the upper and lower reinforcing rolls. A plate rolling machine, comprising: a reinforcing roll reaction force measuring device. 5. A multi-stage plate rolling machine having four or more stages, which measures a roll axial thrust reaction force acting on all rolls other than the reinforcing rolls, and acts in the rolling direction at each rolling fulcrum position of the upper and lower reinforcing rolls. Reinforcement roll reaction force measuring device, at least the thrust reaction force measurement value and the reinforcing roll reaction force measurement value as input data, at least the mill center of the roll axial distribution of the load acting between the rolling material and the work roll A plate rolling machine, comprising: an asymmetry or an arithmetic unit for calculating an asymmetry about a mill center of a roll axial distribution of a load acting between upper and lower work rolls. 6. A roll bending device is provided on at least one set of rolls other than the reinforcing rolls, and the roll chock of at least one roll among the rolls having the roll bending device is a roll chock supporting a radial load and a roll shaft. has a direction of the separated roll chock for supporting the thrust counterforces structure, according to claim 4 or wherein the device for measuring the thrust counterforces acting on the thrust reaction force supporting roll chock is provided 5. The plate rolling machine according to item 5 . 7. A roll bending device is provided on at least one set of rolls other than the reinforcing rolls, and the roll bending device has a set roll bending force.
The plate rolling machine according to claim 4 or 5, further comprising a mechanism capable of adding a vibration component having a frequency of 5 Hz or higher. 8. A roll bending device is provided on at least one set of rolls other than the reinforcing rolls, and a degree of freedom in a roll axial direction is provided between a load loading part of the roll bending device and a roll chock abutting the load loading part. claims, characterized in that it has a slide bearing mechanism having
The plate rolling machine according to 4 or 5 . 9. A roll bending device is provided on at least one set of rolls other than the reinforcing rolls, and elastic deformation against out-of-plane deformation is provided between a load applying part of the roll bending device and a roll chock abutting against the load applying part. claims resistance characterized by having a load transmitting portion of the at least partially liquid in the closed space covered encapsulated consists of 5% or less of the thin outer skin of the maximum value of the roll bending force
The plate rolling machine according to 4 or 5 . 10. A mechanism for axially shifting the rolls in at least one set of rolls other than the reinforcing rolls, and the shift mechanism has a function of giving a minute shift swing with an amplitude of 1 mm or more and a period of 30 seconds or less. Claims characterized by
The plate rolling machine according to any one of 4 to 9 .