JPH11347616A - Method for changing roll cross angle and roll bending force in flying and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the changing method of roll cross angle and roll bending force in flying by which the meandering of a metallic strip is prevented in the case of changing the roll cross angle in rolling and a device which is used for execution. SOLUTION: Relating to a cross angle controller 3, the amount of changing upper cross angle and amount of changing lower cross angle are determined from the roll cross angles θA, θB and roll cross declination αA, αB of a preceding material A and succeeding material B. Relating to the cross angle controller 3, the time T required for the change is calculated from the max. rotational speed VUP. MAX of the upper work rolls 51 and the amount of changing the upper cross angle and, using the obtained time T, the rotational speed VDW of lower work rolls 52 is calculated. To a bending force controller 4, the roll bending forces FW. AO, FW. BO of the preceding material A and succeeding material B are set and, relating to the bending force controller 4, the roll bending force FW. A and roll bending force FW. B, are calculated with time from both roll bending forces FW. AO, FW. BO, the rotational speed VDW of the lower work roll 52 and the max. rotational speed VUP. MAX of the upper work roll 51.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to at least one of a plurality of rolling stands arranged in tandem, wherein a pair of rolling rolls for rolling a metal strip intersect each other in a plane parallel to the metal strip. A method for changing the cross-roll angle and the roll bending force of the two rolling rolls while continuously rolling the metal strip by a cross-roll type tandem rolling mill provided with a cross-roll type rolling stand provided as described above, and its method. It relates to an apparatus used for implementation.

[0002]

2. Description of the Related Art Since the shape, such as crown and flatness, of a metal band greatly affects product quality, it is important to control the shape with high precision. In order to roll a metal strip into a required shape, a cross-roll type tandem rolling mill in which a cross-roll type rolling stand is arranged on at least one of a plurality of rolling stands arranged in tandem is used.

[0003] The following method is disclosed in Japanese Patent Publication No. 63-35325 for controlling the rolling of a metal strip by the tandem rolling mill of the cross roll type. Calculate the optimum roll cross angle and roll bending force based on the material specifications, length, width, thickness, etc. of the metal strip to be rolled, the target crown, rolling load, and target flatness at each rolling stand. Then, after adjusting the roll cross angle and the roll bending force so as to obtain the obtained values, the rolling of the metal strip is started. During rolling, the crown and flatness of the metal strip are detected, and based on the obtained deviation between the actual crown and the target crown and the deviation between the actual flatness and the target flatness, the roll cross angle and / or the roll bend. Feedback control of force.

In a tandem rolling mill, continuous rolling is performed on a metal strip formed by connecting a tail and a top of a plurality of coils having different dimensional specifications. In such a metal strip, a target crown and a target flatness are separately determined corresponding to portions having different dimensional specifications of the metal strip. Must be rolled so that

However, in the method disclosed in JP-B-63-35325, the roll cross angle and / or the roll bend are determined based on the deviation between the actual crown and the target crown and the deviation between the actual flatness and the target flatness. When a metal strip having a plurality of portions having different dimensional specifications is continuously rolled for feedback control of the force, the portions cannot be controlled to a predetermined shape from the start of rolling of each portion.

For this reason, the present applicant has disclosed in Japanese Patent Application Laid-Open No. 4-351213 the change of the roll cross angle and the roll bending force in accordance with the timing at which the connecting portions of the respective parts constituting the metal strip pass through the cross roll rolling stand. Suggested how to. The change of the roll cross angle is performed to control the shape of the portion to be rolled of the metal strip to a required shape, but due to mechanical limitations, it takes a predetermined time from the start of the change to the end, During that time, the accuracy of shape control is reduced.
On the other hand, since the roll bend force can be changed in a short time, by changing the roll cross angle and the roll bend force, the metal strip can be rolled into the required shape even while the roll cross angle is changed. However, the shape of each part of the metal strip can be controlled with high accuracy from the start of rolling.

[0007]

By the way, in the tandem rolling mill of the cross roll type, lubricating oil is interposed between the upper and lower work rolls and the metal strip in order to reduce the friction between them, but the lower face of the metal strip is not provided. Since the lubricating oil drops due to weight and mechanical vibration, the friction coefficient between the metal band and the lower work roll is larger than the friction coefficient between the metal band and the upper work roll. Therefore, there was a problem that the metal band meandered during rolling.

FIG. 10 is an explanatory view for explaining the principle of meandering of the metal band. In the figure, reference numeral 1 denotes a metal band. The upper work roll 51 faces the transfer area of the metal strip 1 transferred in the arrow direction.
And a lower work roll 52. Both work rolls 5
In order to make the shape of the metal strip 1 into a required shape, 1 and 52 intersect each other at the center of the work rolls 51 and 52 so that the roll cross angle formed by both central axes becomes θ. ,
The upper and lower work rolls 51 and 52 have an upper cross angle formed by a reference axis K orthogonal to the pass line of the metal strip 1 and a center axis of the upper work roll 51, and a center axis of the reference axis K and the lower work roll 52. The lower cross angles, which are the angles formed by the two, are each set to θ / 2.

The metal strip 1 is rolled by entering the metal strip 1 between the work rolls 51 and 52 from a direction perpendicular to the reference axis K. The metal strip 1 from the upper work roll 51, with vectors y ₅₁ having a propulsion force according to the coefficient of friction between the upper work roll 51 and the metal strip 1 in a direction perpendicular to the central axis of the upper work roll 51 acts , Lower work roll 52
From acts vector y ₅₂ having a propulsion force according to the coefficient of friction between the lower work roll 52 and the metal strip 1 in a direction perpendicular to the central axis of the lower work roll 52, the metal strip 1 vector y ₅₁
And it is transferred to the vector y ₅₂ in the direction of the synthesized composite vector y _50.

As mentioned above, the metal strip 1 and the upper work roll
According to the coefficient of friction between the metal strip 1 and the lower work roll 52,
Since larger coefficient of friction between the a vector y ₅₁ <vector y _52, the direction of the resultant vector y _50, the reference axis K
From the axis perpendicular to the axis of the lower work roll 52. Therefore, in the method disclosed in JP-A-4-351213, although capable of rolling metal strip in a required shape even while changing the roll cross angle, the metal strip 1 by the inclination of the combined vector y ₅₀ described above There is a possibility that troubles such as meandering and narrowing breakage may occur.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a roll cross corresponding to a roll cross angle before and after a change based on a relationship between the roll cross deflection angle and the roll cross angle. The declination is calculated respectively, and using the calculated roll cross declination and the roll cross angle before and after the change, the amount of rotation of both rolling rolls provided on the cross roll type rolling stand is obtained, and each obtained rotation is obtained. When the roll cross angle is changed during rolling by rotating the corresponding rolling rolls so as to have a moving amount, a running roll cross angle / roll bending force changing method capable of preventing meandering of the metal band and It is to provide an apparatus used for implementation.

[0012]

According to a first aspect of the present invention, there is provided a method for changing a running roll cross angle and a roll bending force, wherein a plurality of rolling stands including a cross roll type rolling stand in which a pair of rolling rolls cross each other are tandem. While the metal strip is continuously rolled by the rolling mill disposed at the same time, the roll cross angle of the two rolling rolls is changed, and the roll bending force applied to both rolling rolls is changed according to the change of the roll cross angle. In the method, a relationship between the cross roll deflection angle and the roll cross angle of the rolling roll is obtained in advance, and based on the relationship, a roll cross deflection angle corresponding to the roll cross angle before and after the change is calculated and obtained. Using the two roll cross deflection angles and the roll cross angles before and after the change, the amount of rotation for rotating the two rolling rolls in a plane parallel to the metal band is determined. , Characterized in that for each rotation of the rolling rolls corresponding to become each rotational amount determined.

According to a second aspect of the invention, there is provided a method for changing a roll cross angle and a roll bend force during traveling, according to the first aspect, wherein a first rotation speed for rotating one of the rolling rolls provided on the cross roll type rolling stand is predetermined. Calculating the time required to rotate the one rolling roll based on the first rotating speed and the rotating amount of the one rolling roll, based on the obtained time and the rotating amount of the other rolling roll. Calculating a second rotation speed for rotating the other roll, rotating the one roll at a first rotation speed, and rotating the other roll at a second rotation speed. It is characterized by making it.

A method of changing the roll cross angle and roll bend force during running according to a third aspect of the present invention is the method according to the second aspect, wherein the first and second rotation speeds are used to change the roll cross angle during the change of the roll cross angle. The roll bend force to be applied is calculated over time, and the roll bend force applied to the two rolling rolls is changed so as to obtain the obtained roll bend force.

According to a fourth aspect of the present invention, in the method for changing the roll cross angle and the roll bend force according to any one of the first to third aspects, a specific position in the longitudinal direction of the metal strip is determined in advance, and the specific position is a cross position. It is characterized in that the change of the roll cross angle and the roll bending force is started at an appropriate timing before reaching the roll type rolling stand.

According to a fifth aspect of the present invention, there is provided a method for changing a roll cross angle and a roll bend force during running according to any one of the first to third aspects, wherein a metal band formed by connecting a preceding material and a following material is used.
The change of the roll cross angle and the roll bending force is started at an appropriate timing before the connecting portion of the preceding material and the following material reaches the cross-roll type rolling stand.

[0017] A running roll cross angle / roll bending force changing device according to a sixth aspect of the present invention is a rolling device in which a plurality of rolling stands including a cross roll type rolling stand in which a pair of rolling rolls cross each other are arranged in tandem. A device for changing the roll cross angle of both rolling rolls by a rotating machine while continuously rolling a metal strip with a rolling machine, and changing the roll bending force applied to both rolling rolls according to the change of the roll cross angle by a vendor. A means for setting a relationship between the roll cross angle and the roll cross angle of the rolling roll in advance, and calculating a roll cross angle corresponding to the roll cross angle before and after the change based on the relationship, By using the obtained roll cross deflection angle and the roll cross angle before and after the change, the two rolls are rotated in a plane parallel to the metal band. Means for determining that rotation amount, respectively,
Command output means for outputting, to the rotating machine, a command for rotating each of the corresponding rolling rolls so as to attain the determined amount of rotation.

According to a seventh aspect of the present invention, there is provided a running roll cross angle / roll bending force changing device according to the sixth aspect, wherein the first rotation speed for rotating one of the rolling rolls provided on the cross roll type rolling stand is predetermined. Means for calculating a time required to rotate the one rolling roll based on the first rotating speed and the amount of rotation of the one rolling roll;
Means for calculating a second rotation speed for rotating the other rolling roll based on the obtained time and the amount of rotation of the other rolling roll. A command to rotate the one rolling roll and rotate the other rolling roll at a second rotating speed is output to a rotating machine.

According to an eighth aspect of the present invention, the inter-running roll cross angle / roll bending force changing device according to the seventh aspect uses the first rotation speed and the second rotation speed to apply during the change of the roll cross angle. Means for calculating the roll bend force to be performed over time, and means for outputting to the bender a command to change the roll bend force applied to the two rolling rolls so as to obtain the obtained roll bend force. Features.

Hereinafter, the principle of the present invention will be described. FIG. 6 is an explanatory diagram for explaining the principle of the present invention.
Is a metal strip. The upper work roll 51 and the lower work roll 52 face the transfer area of the metal strip 1 transferred in the arrow direction.
Is provided. The two work rolls 51 and 52 cross each other at the center of the work rolls 51 and 52 so that the roll cross angle becomes θ in order to make the shape of the metal strip 1 into a required shape.

The upper work roll 51 has an upper cross angle of (θ / 2 + α), and the lower work roll 52 has a lower cross angle of (θ / 2−α). , 52 are rotated by a roll cross angle α in a plane parallel to the metal strip 1 without changing the roll cross angle.

The metal strip 1 is rolled between the work rolls 51 and 52 from a direction perpendicular to the reference axis K. The metal strip 1 from the upper work roll 51, with vectors y ₅₁ having a propulsion force according to the coefficient of friction between the upper work roll 51 and the metal strip 1 in a direction perpendicular to the central axis of the upper work roll 51 acts , Lower work roll 52
From acts vector y ₅₂ having a propulsion force according to the coefficient of friction between the lower work roll 52 and the metal strip 1 in a direction perpendicular to the central axis of the lower work roll 52, the metal strip 1 vector y ₅₁
And it is transferred to the vector y ₅₂ in the direction of the synthesized composite vector y _50.

As described above, the metal strip 1 and the upper work roll
According to the coefficient of friction between the metal strip 1 and the lower work roll 52,
Since larger coefficient of friction between the a vector y ₅₁ <vector y _52, if not to rotate the upper and lower work rolls 51 and 52 only roll cross polarization angle alpha, the direction of the resultant vector y _50, the reference axis K Slightly tilts from the axis perpendicular to the axis to the axis perpendicular to the center axis of the lower work roll 52. However, by rotating the upper and lower work rolls 51 and 52 by the roll cross deflection angle α, the above-described inclination is eliminated, and the combined vector y
_{Since 50} is a direction orthogonal to the reference axis K, meandering is prevented.

In the first, fourth, fifth and sixth aspects of the present invention, as shown in FIG. 7, the relationship between the roll cross angle and the roll cross angle for preventing meandering is determined. , The roll cross angle α corresponding to the roll cross angle θ before and after the change is determined for each coil constituting the metal body by rolling conditions such as α = k · θ (k: roll cross angle and rolling load). Parameter). Then, by using the roll cross angle before and after the change and the corresponding roll cross deflection angle, the amount of rotation of both rolling rolls provided in the cross roll type rolling stand is obtained.

The above-mentioned roll cross angle is calculated as an angle equivalent to the roll mechanical crown amount required for rolling a metal strip into a predetermined shape. However, the roll bending force also affects the roll mechanical crown amount. It has been known. That is, when the roll cross angle and the roll bending force satisfy the relationship of the following expression (1), the metal strip can be rolled into a predetermined shape. a ₀ + a ₁ · F _W + a ₂ · θ ² = 0 (1) where a ₀ : a parameter determined by the metal band a ₁ : a parameter determined by the metal band a ₂ : a parameter determined by the metal band F _W : roll bending force θ: Roll cross angle

FIG. 8 is a graph showing the relationship between the roll cross angle and the roll bending force when the metal strip formed by connecting the preceding material and the following material is continuously rolled. The abscissa indicates the roll cross angle. In FIG. 8, a curve L _A is a graph showing a relationship between a roll cross angle and a roll bending force according to the preceding material, and a curve L _B is
It is a graph which shows the relationship between the roll cross angle and roll bend force regarding a following material. As is clear from FIG. 8, the curve L _A
And both the curve L _B, according to the roll cross angle becomes large, the roll bend force is small.

When rolling the preceding material and the following material, the optimum roll bending force is an average value of the maximum roll bending force F _{W, MAX} and the minimum roll bending force F _{W, MIN} . This is because the width for adjusting the roll bending force is large. The optimum roll bend force and the curve L _A and curve L _B and the point intersects P
_A0, P _B0 corresponding to theta _A, the theta _B is optimal roll cross angle of the preceding material and the following material.

Transition from rolling of preceding material to rolling of succeeding material
If the roll cross angle is θ_AFrom θ _BChange to this
When the roll cross angle changes, the roll bend force
And F_{W, A0}(Point P_A0Roll bend force) → F_{W, A1}(Point P
_A1Roll bend force) → F_{W, B1}(Point P_B1Roll bend
Force) → F_{W, B0}(Point P_B0Roll bend force)
Depending on whether the roll cross angle is being changed,
The shape of the band can be maintained well. Also, both rolling
The roll is rotated to the required amount of rotation as described above.
Let it. This allows the roll cross angle to change
The roll cross angle has been changed and the roll cross angle is being changed
The meandering is prevented from occurring.

By the way, the roll cross angle and the roll cross angle before the change, that is, the roll cross angle and the roll cross angle relating to the preceding material are denoted by θ _A and α _A, and the roll cross angle and the roll cross declination after the change That is, assuming that the roll cross angle and the roll cross deflection angle relating to the following material are θ _B and α _B ,
The amount of rotation of one rolling roll is represented by the following equation (2), the amount of rotation of the other rolling roll is represented by the following equation (3), and the difference between the two rotating amounts is represented by the following equation (4). . _{(Θ B / 2 + α B} ) - (θ A / 2 + α A) ... (2) (θ B / 2-α B) - (θ A / 2-α A) ... (3) {(θ B / 2 + α B) _{- (θ A / 2 + α} A)} - {(θ B / 2-α B) - (θ A / 2-α A)} = 2 (α B -α A) ... (4)

Normally, since equation (4) does not become zero, both rolling rolls of the cross roll type rolling stand are started to rotate simultaneously, and when both are rotated at the same speed, one of the two rolling rolls is rotated. However, the turning operation ends before the other. In this case, the metal band meanders as follows.

FIG. 9 is an explanatory diagram for explaining the meandering of the metal band which occurs when the turning operation of the other rolling roll is completed before the turning operation of the other rolling roll. In the figure, parts corresponding to the parts shown in FIG. 6 are denoted by the same reference numerals, and description thereof will be omitted.

In order to set the roll cross angle after change to θ _B and the roll cross deflection angle to α _B , the upper work roll 51 is set to θ _B / 2.
+ Α _B to rotate the lower work roll 52 to θ _B / 2
pivots to the position of the alpha _B. At this time, since the coefficient of friction between the upper work roll 51 and the metal band 1 is smaller than the coefficient of friction between the lower work roll 52 and the metal band 1, the amount of rotation of the upper work roll 51 is smaller than that of the lower work roll 52. It is larger than the amount of rotation. Therefore, when the rotation of the upper work roll 51 and the lower work roll 52 is started simultaneously and both are rotated at the same speed, when the rotation of the lower work roll 52 ends, the upper work roll 51 is rotated.
Has been rotated only to the position (θ _B / 2 + α _B −ε).

At this time, as shown in FIG. 9, a vector y ₅₁₁ of a propulsive force applied to the metal strip 1 by the upper work roll 51 is given by:
Combined vector y ₅₀₁ in which the lower work roll 52 is obtained by synthesizing the vector y ₅₂ of the propulsion force applied to the metal strip 1 is biased to the shaft side perpendicular to the central axis of the lower work roll 52 from the reference axis K, this deviation The metal strip 1 meanders.

In the second, fourth, fifth and seventh inventions, when changing the cross roll angle of both rolling rolls of the cross roll type rolling stand, the rotation speed of one of the rolling rolls is set, The rotating speed of the other rolling roll is calculated so that the time required for rotating the two rolling rolls is the same, and the other rolling roll is rotated at the rotating speed. Meandering is prevented.

In the third, fourth, fifth and eighth inventions, the roll cross angle being changed can be calculated over time using the rotational speeds of both rolling rolls, and the calculation result From the graph shown in FIG. 8, the roll bending force to be applied during the change of the roll cross angle is calculated over time. Then, during the change of the roll cross angle, the roll bend force of both rolling rolls is changed so as to become the roll bend force calculated as described above. Thereby, the shape of the metal strip can be controlled with high precision during the change of the roll cross angle.

[0036]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the apparatus according to the present invention, in which three of the five rolling stands are cross-roll type rolling stands. A metal band 1 formed by connecting a preceding material A and a following material B having different dimensional specifications at a connecting portion C is transferred in the direction of the arrow, and a pair of upper and lower work rolls 51,
Five stands # 1 to # 5 including a backup roll 52 and a backup roll 61 sandwiching both work rolls 51 and 52 are arranged in tandem at appropriate intervals.

The fourth and fifth stands # 4, # 5 are paired with work rolls 51, 52 and backup rolls 61, 62.
Are arranged in parallel with a reference axis orthogonal to the pass line of the metal strip 1, and the pressing positions of the fourth and fifth stands # 4 and # 5 are adjusted by a pressing device (not shown).

Further, upper work rolls 51, 5 of first to third stands # 1 to # 3, which are cross-roll type rolling stands, are provided.
1, 51 and the upper backup rolls 61, 61, 61 are moved by upper roll rotating devices 11, 12, 13 and the lower work rolls 52, 52, 52 and the lower backup rolls of the first to third stands # 1 to # 3. Rolls 62, 62, 62 are lower roll rotating devices 21, 22, 23.
Accordingly, each of them is separately rotated in a plane parallel to the metal band 1. Upper roll rotation device 11, 1
2, 13 and the lower roll rotating devices 21, 22, 23 are controlled by the cross angle control device 3 to form an upper cross angle between the upper work rolls 51, 51, 51 and the above-described reference axis, and a lower work roll 52,
Drive control is performed such that the lower cross angle between the reference axes 52 and 52 becomes a required angle.

The upper and lower work rolls 51, 52, 51, 52, 51, 52 of the first to third stands # 1 to # 3 are provided with benders 31, 32, 33 for applying a bending force thereto. 31,
The drives 32 and 33 are driven and controlled by a bend force control device 4 for controlling the bend force applied to the upper and lower work rolls 51, 52, 51, 52, 51, 52. Each of the first to third stands # 1 to # 3 is also provided with the above-described pressing device, and the pressing position of each of the stands # 1 to # 3 is adjusted by each pressing device.

A connecting portion C between the preceding material A and the following material B
Is tracked by the tracking device 5, and the tracking device 5 moves the cross-angle control device 3 and the bend force control device 4 up and down immediately before the connection portion C reaches each of the stands # 1 to # 5. A command to start changing the cross angle and the roll bending force is given.

Cross angle control device 3 and bend force control device
4 shows the dimensional specifications of the preceding material A and the following material B of the metal strip 1;
Material, target crown at each rolling stand, target flatness
Rolling information in which rolling information such as degree and target thickness is registered
Rolling information on the metal strip 1 is given from the database 2.
The cross angle control device 3 is
Based on the obtained rolling information, the preceding material A of the metal strip 1 and
Roll bending force F for following material B_WIs 1/2 (F_{W, MAX}
+ F_{W, MIN}) So that the roll cross angle θ _A, Θ_B
Is calculated according to each of the first to third stands # 1 to # 3
I do.

As shown in FIG. 7, in the cross angle control device 3, a relational expression between the roll crossing angle θ and the optimum roll crossing deviation α is set in advance. The optimum roll cross deflection angles α _A and α _B corresponding to θ _A and θ _B are obtained, respectively. Then, the cross angle controller 3 calculates the roll cross angle θ in the following equations (5) and (6).
_A , θ _B and the optimal roll cross declination α _A , α _B are substituted for the upper cross angle Θ _{UP, A} and the lower cross angle Θ _{DW, A of the} preceding material _A.
Are calculated respectively. Similarly, the cross angle control device 3
The following equations (7) and (8) show the roll cross angles θ _A , θ _B
And optimum roll cross polarization angle alpha _A, by substituting the alpha _B, calculates cross angle theta _UP on the following material _{B, B} and lower cross angle theta _{DW, B,} respectively. Θ _{UP, A} = θ _A / 2 + α _A (5) Θ _{UP, B} = θ _B / 2 + α _B (6) Θ _{DW, A} = θ _A / 2-α _A (7) Θ _{DW, B} = θ _B / 2−α _B (8)

The cross angle control device 3 determines the speed at which the upper work roll 51 is rotated, for example, by its maximum rotation speed V.
_{UP, MAX} , and the following equation (9) defines the upper cross angles Θ _{UP, A} , Θ _{UP, B} of the preceding material A and the following material B and the maximum rotation speed V _{UP, MAX.}
Is substituted to calculate the time T required to rotate the upper work roll 51 when the roll cross angle is changed. _{T = {(θ B / 2} + α B) - (θ A / 2 + α A)} / V UP, MAX ... (9)

Then, the cross angle control device 3 substitutes the obtained time T and the lower roll angles Θ _{DW, A} , Θ _{DW, B} of the preceding material A and the following material _B into the following equation (10). The rotation speed V _DW of the lower work roll 52 is calculated. _{V DW = {(θ B /} 2-α B) - (θ A / 2-α A)} / T ... (10)

The cross angle controller 3 includes a lower work roll 52
After calculating the rotation speed V _DW, maximum rotation speed V _UP of the pivoting velocity V _DW and the upper work roll _{51, MAX,} and the roll cross angle theta _A, a theta _B, giving the bend force control apparatus 4.

The bend force control device 4 includes a preceding material A and a rear material A.
Roll bending force F of row material B_{W, A0}, F _{W, B0}｛F_{W, A0}= F
_{W, B0}= 1/2 (F_{W, MAX}+ F_{W, MIN})｝ Has been set
The bend force control device 4 controls both roll bend forces F_{W, A0},
F_{W, B0}, And the lower wire provided from the cross angle controller 3.
Rotation speed V of crawl 52_DWAnd the upper work roll 51
Large rotation speed V_{UP, MAX}Into the following equations (11) and (12)
After changing the roll cross angle,
Roll bending force until the tied part C reaches the rolling stand
F_{W, A}, And after the connecting portion C passes through the rolling stand
Roll bend force until change of roll cross angle is completed
F_{W, B}Is calculated over time. F_{W, A}(T) = F_{W, A0}-A_{2, A}・ ｛Θ_A+ (V_{UP, MAX}+ V_DW) ・ T｝^Two / A_{1, A} … (11) F_{W, B}(T) = F_{W, B0}-A_{2, B}・ ｛Θ_B+ (V_{UP, MAX}+ V_DW) ・ (Tt)｝^Two/ A_{1, B} … (12) where a_{1, A}: Parameter related to preceding material a_{2, A}: Parameter related to preceding material a_{1, B}： Parameters for following material a_{2, B}： Parameter related to following material

Prior to the rolling of the metal strip 1, the cross angle control device 3 controls the upper cross angle (θ _A / 2 + α _A ) and the lower cross angle (θ _A / 2) determined according to the first to third stands # 1 to # 3. θ _A
/ 2-α _A ), the first to third stands {
The roll cross angles and the roll cross biases of the first to third stands # 1 to # 3 are given to the upper roll rotation devices 11, 12, 13 and the lower roll rotation devices 21, 22, 23, respectively. The angle is adjusted to a value corresponding to the preceding material A.

Further, the bend force control device 4
Prior to rolling, the roll bending force F _{W, A0}Directive to grant
To the vendors 31, 32, 33 of the first to third stunners 1 # 1 to # 3.
To the first to third stands # 1 to # 3
Adjust the bend force.

Each time the tracking device 5 issues a change start command for the first to third stands # 1 to # 3, the cross angle control device 3 rotates the upper roll of the first to third stands # 1 to # 3. The upper cross angle change amount {([theta] _B / 2 + [alpha] _B )-([theta] _A / 2 + [alpha] _A )} and the maximum rotation speed _{VUP, MAX} are given to the moving devices 11, 12, and 13, respectively. 21, 22, and 23, the lower cross angle change amount ２− (θ _B / 2−
α _B ) − (θ _A / 2−α _A )} and the rotation speed V _DW, and the roll cross angle and the roll cross deflection angle of the first to third stands # 1 to # 3 according to the following material B. Value.

As described above, since the roll cross angle is changed along with the roll cross angle, the trailing material B is prevented from meandering. Also, the rotation speed V of the upper work roll 51
_Since the rotation speed V _DW of the lower work roll 52 is determined according to _{UP, MAX} , the rotation start timing and the rotation end timing of the upper work roll 51 and the lower work roll 52 are the same, and During the rotation of the roll 51 and the lower work roll 52,
No meandering occurs in the metal strip 1.

The bend force control device 4 includes a tracking
From the storage device 5 to the first to third stands # 1 to # 3
Each time a start command is given, the rotation speed of the upper work roll 51
Degree V _{UP, MAX}And the rotation speed V of the lower work roll 52_DWAccording to
Roll bending force F calculated over time_{W, A}(T) and b
Re-bend force F_{W, B}(T) is replaced with the first to third stands # 1 to # 1
$ 3 Vendors 31, 32, and 33, each stand # 1 to $ 3
Adjust the roll bend force. This allows the upper work
During the rotation of the roll 51 and the lower work roll 52, the metal strip 1 is formed.
The occurrence of shape defects is prevented.

FIGS. 2 and 3 are flowcharts showing the control procedure of the vertical cross angle and the roll bend force by the cross angle control device 3 and the bend force control device 4 shown in FIG. The cross angle control device 3 and the bend force control device 4 read necessary information such as information and parameters relating to the preceding material A and the following material B from the rolling information database 2 (step S1) and store them (step S2). ).

The cross angle control device 3 determines that the roll bending force _FW for the preceding material A and the succeeding material B is １ ／ based on the stored information for the first to third stands # 1 to # 3.
The roll cross angles θ _A , θ _B are respectively calculated so as to be (F _{W, MAX} + F _{W, MIN} ) (step S3), and based on the relationship shown in FIG. 7, the roll cross angles θ _A , θ are obtained. _The roll cross deflection angles α _A and α _B corresponding to _B are obtained (step S4).

The cross angle controller 3 substitutes the obtained roll cross angles θ _A , θ _B and roll cross declination α _A , α _B into the equations (5) to (8), and Trailing material B
The upper cross angle Θ _{UP, A} , Θ _{UP, B} and the lower cross angle Θ _{DW, A} , Θ _{DW, B} are calculated, and the upper cross angle Θ _{UP, B}
The upper cross angle Θ _{UP, A} of the preceding material A is subtracted from the preceding material A to obtain the upper cross angle change amount, and the lower cross angle Θ _DW, A of the preceding material _A is subtracted from the lower cross angle Θ _{DW, B of the} succeeding material B. Then, the lower cross angle change amount is obtained (steps S5 and S6).

The cross angle control device 3 determines the speed at which the upper work roll 51 is turned, for example, by the maximum turning speed V.
_UP, defined _MAX (step S7), (9) formula preceding material A and the cross angle theta _UP on the following material _{B, A,} Θ _UP, B and maximum times substituting the dynamic speed V _MAX and time mentioned above T is calculated (step S8). The cross angle control device 3 calculates the obtained time T and the lower roll angles Θ _{DW, A} , Θ _{DW, B of the} preceding material A and the following material _B.
Into the equation (10), the rotation speed V _DW of the lower work roll 52 is obtained.
Is calculated (step S9), and the bending speed V _DW , the maximum turning speed V _{UP, MAX of} the upper work roll 51, and the roll cross angles θ _A , θ _B are given to the bend force control device 4.

The bend force control device 4 includes a preceding material A and a rear material A.
Roll bending force F of row material B_{W, A0}, F _{W, B0}｛F_{W, A0}= F
_{W, B0}= 1/2 (F_{W, MAX}+ F_{W, MIN})｝ Has been set
The bend force control device 4 controls both roll bend forces F_{W, A0},
F_{W, B0}, And the lower wire provided from the cross angle controller 3.
Rotation speed V of crawl 52_DWAnd the upper work roll 51
Large rotation speed V_{UP, MAX}Into the equations (11) and (12)
And roll bend force F_{W, A}And roll bending force F_{W, B}To
The calculation is performed over time (step S10).

Prior to the rolling of the metal strip 1, the cross angle control device 3 determines the upper cross angle (θ _A / 2 + α _A ) and the lower cross angle (θ _A ) determined according to the first to third stands # 1 to # 3. θ _A
/ 2-α _A ), and generates the rotation commands, and sends them to the upper roll rotation device of the first to third stands # 1 to # 3.
11, 12, 13 and the lower roll rotating devices 21, 22, 23 respectively (step S <b> 11), and the first to third stands {1 ♯}
The roll cross angle and the roll cross deflection angle of No. 3 are adjusted to values according to the preceding material A. Also, the bend force control device 4
Generates a command to apply the roll bending force F _{W, A0,} and sends it to the vendors 31, 32, 33 of the first to third stands # 1 to # 3.
(Step S12) to adjust the roll bending forces of the first to third stands # 1 to # 3.

The cross angle control device 3 and the bend force control device 4 are provided from the tracking device 5 to the first to third stands # 1.
It is determined whether or not a change start command according to # 3 has been given (step S13). If the cross angle control device 3 determines that the change start command has been given, the cross angle control device 3 sends the corresponding upper stand to the upper roll rotating device. cross angle change amount _{{(θ B / 2 + α} B) -
(Θ _A / 2 + α _A )} and the maximum rotation speed V _{UP, MAX} respectively, and the lower roll rotation device is provided with a lower cross angle change amount ((θ _B / 2−α _B ) − (θ _A / 2). -Α _A )｝ and the rotation speed V _DW are given (step S14), and the roll cross angle and the roll cross angle of the stand are changed.

When the bend force control device 4 determines that the tracking device 5 has issued a change start command for the first to third stands # 1 to # 3, the roll bend force _FW calculated over time is determined. _{, A} (t) and roll bending force F
_{W, B} (t) is given to the vendor of the corresponding stand (step S15), and the roll bending force of the stand is adjusted.

Although the present embodiment has been described with reference to the case where a metal band formed by connecting two coils is used, the present invention is not limited to this.
It goes without saying that the upper work roll and the lower work roll may be rotated and the roll bending force may be adjusted in accordance with the timing at which an appropriate portion in the longitudinal direction passes through the rolling stand.

[0061]

Next, the result of rolling a metal strip by the apparatus shown in FIG. 1 will be described. 4 and 5 are graphs showing the results at the first stand when the metal strip is rolled by the apparatus shown in FIG. 1, FIG. 4 (a) shows the change pattern of the upper cross angle, and FIG. 9 shows a change pattern of a lower cross angle. FIG. 4C shows a change pattern of the roll cross angle, and FIG. 4D shows a change pattern of the roll bending force. On the other hand, FIG. 5E shows the result of measuring the shape of the metal band, and FIG. 5F shows the result of measuring the meandering amount of the metal band. Note that, in both figures, arrows indicate connection parts.

The maximum rotation speed of the upper roll rotation device and the lower roll rotation device is 0.07 deg / sec. Also, the first
-In the third stand, the optimum roll cross angle for the preceding material is 0.35deg, 0.28deg, 0.2
The optimum roll cross angles for the following material were 0.78 deg, 0.63 deg, and 0.55 deg, respectively.

On the other hand, in the first to third stands, the parameters k for obtaining the optimum roll cross declination were 0.15, 0.13, and 0.10. In the first to third stands, parameters a _{2, A} / a _{1, A} used for calculating the roll bending force of the preceding material are 286, 281, 275, respectively, and the roll of the following material is used. The parameters a _{2, B} / a _{1, B} used for calculating the bending force are as follows:
They were 291, 286 and 281 respectively.

When the roll cross angle is changed before and after the connecting portion passes through the first stand as shown in FIG. 4C, the upper cross angle is changed as shown in FIGS. 4A and 4B. By changing the lower cross angle and the roll cross angle, the roll cross angle was changed together with the roll cross angle. As shown
The change amount of the lower cross angle is smaller than the change amount of the upper cross angle, but the change speed of the lower cross angle (the rotation speed of the lower work roll) is changed according to the change speed of the upper cross angle (the rotation speed of the upper work roll). ), The start time and the end time of the change of the vertical cross angle are matched.

Further, the roll bending force is changed in accordance with the change in the vertical cross angle. At this time, as shown in FIG. 4D, based on the change speed of the vertical cross angle, the roll bend force is increased from approximately 25 tf from the start of the change until the connecting portion reaches the first stand. 10 tf, the roll bend force jumps to approximately 40 tf at the timing when the connection portion reaches the first stand, and the roll bend force is reduced until the change is completed after the connection portion passes through the first stand. It was gradually reduced to approximately 25 tf.

As a result, as shown in FIG. 5 (e), the metal strip is rolled into a target shape at any position in the rolling direction, and as shown in FIG. Had been prevented.

[0067]

As described above in detail, in the first, fourth, fifth and sixth aspects of the present invention, the roll cross angle is changed according to the change of the roll cross angle, and the roll cross angle is being changed. The occurrence of meandering is suppressed.

In the second, fourth, fifth and seventh inventions, when changing the cross roll angle of both rolling rolls of the cross roll type rolling stand, the rotation speed of one of the rolling rolls is set, The rotation speed of the other rolling roll is calculated so that the time required for the rotation of the two rolling rolls is the same, and the other rolling roll is rotated at the rotation speed. Meandering of the metal strip is prevented.

According to the third, fourth, fifth and eighth aspects of the present invention, meandering of the metal band can be prevented while changing the roll cross angle, and the shape of the metal band can be controlled with high precision. The present invention has excellent effects.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an apparatus according to the present invention.

FIG. 2 is a flowchart illustrating a control procedure of a vertical cross angle and a roll bend force by the cross angle control device and the bend force control device illustrated in FIG. 1;

FIG. 3 is a flowchart showing a control procedure of a vertical cross angle and a roll bend force by the cross angle control device and the bend force control device shown in FIG. 1;

FIG. 4 is a graph showing a result at a first stand when a metal strip is rolled by the apparatus shown in FIG. 1;

FIG. 5 is a graph showing a result of a first stand when a metal strip is rolled by the apparatus shown in FIG. 1;

FIG. 6 is an explanatory diagram illustrating the principle of the present invention.

FIG. 7 is a graph showing a relationship between a roll cross angle and a roll cross deflection angle.

FIG. 8 is a graph showing a relationship between a roll cross angle and a roll bending force when a metal strip formed by connecting a preceding material and a following material is continuously rolled.

FIG. 9 is an explanatory diagram illustrating meandering of the metal band that occurs when the rotation operation of the other rolling roll is completed before the rotation operation of the other rolling roll.

FIG. 10 is an explanatory diagram illustrating the principle of meandering of a metal band.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal strip 3 Cross angle control device 4 Bend force control device 11 Upper roll rotation device 12 Upper roll rotation device 13 Upper roll rotation device 21 Lower roll rotation device 22 Lower roll rotation device 23 Lower roll rotation device 31 Vendor 32 Vendor 33 Vendor 51 Upper work roll 52 Lower work roll 61 Upper backup roll 62 Lower backup roll A Leading material B Trailing material C Connection site

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B21B 37/68 B21B 37/00 116J 135

Claims (8)

[Claims] 1. A roll mill in which a plurality of rolling stands including a cross roll type rolling stand in which a pair of rolling rolls cross each other are arranged in tandem to continuously roll a metal strip. In the method of changing the roll cross angle of, and changing the roll bending force applied to both rolling rolls according to the change of the roll cross angle, the relationship between the cross roll deflection angle and the roll cross angle of the rolling roll is obtained in advance. Each roll cross angle corresponding to the roll cross angle before and after the change is calculated based on the relationship, and the two rolls are rolled using both the obtained roll cross angle and the roll cross angle before and after the change. The amount of rotation to be rotated in a plane parallel to the metal strip is determined, and the corresponding rolling roll is rotated so that the determined amount of rotation is obtained. An inter-running roll cross angle and the roll bending force how to change the symptoms. 2. A first rotation speed for rotating one rolling roll provided on a cross-roll type rolling stand is determined in advance,
Based on the first rotation speed and the amount of rotation of the one rolling roll, a time required to rotate the one rolling roll is calculated, and based on the obtained time and the amount of rotation of the other rolling roll. Calculating a second rotating speed for rotating the other rolling roll, rotating the one rolling roll at a first rotating speed, and rotating the other rolling roll at a second rotating speed. The method for changing the roll cross angle and roll bend force between runs according to claim 1. 3. A roll bend force to be applied during the change of the roll cross angle is calculated with time using the first rotation speed and the second rotation speed, and the calculated roll bend force is obtained. 3. The method according to claim 2, wherein the roll bending force applied to the two rolling rolls is changed. 4. A specific position in the longitudinal direction of the metal strip is determined in advance, and the change of the roll cross angle and the roll bending force is started at an appropriate timing before the specific position reaches the cross roll type rolling stand. 4. The method for changing the roll cross angle and roll bend force during running according to any one of 1 to 3. 5. Using a metal band formed by connecting a preceding material and a following material, a roll cross angle and a roll cross angle are set at an appropriate timing before a connecting portion of the preceding material and the following material reaches a cross-roll type rolling stand. 2. A change in roll bend force is started.
4. The method for changing the roll cross angle and roll bend force during running according to any one of the above-described items. 6. A rolling mill in which a plurality of rolling stands including a cross roll type rolling stand in which a pair of rolling rolls cross each other are arranged in tandem to continuously roll a metal strip while the two rolling rolls are being rolled. In a device that changes the roll cross angle of the rolling roll by a rotating machine and changes the roll bending force applied to both rolling rolls according to the change of the roll cross angle by a bender, the roll cross angle of the rolling roll and the roll cross angle The relationship is set in advance, and based on the relationship, means for calculating the roll cross declination corresponding to the roll cross angle before and after the change, and the obtained roll cross declination and the roll cross angle before and after the change, respectively. Means for determining the amount of rotation by which the two rolling rolls are rotated in a plane parallel to the metal strip, and the determined amount of rotation. An inter-running roll cross angle, roll bend force changing device characterized in that it comprises a command to rotate the corresponding rolling rolls each and command output means for outputting to the times motives. 7. A first rotation speed for rotating one of the rolling rolls provided on a cross-roll type rolling stand is determined in advance, and based on the first rotation speed and the rotation amount of the one rolling roll. Means for calculating the time required to rotate the one roll, and a second rotation speed for rotating the other roll based on the obtained time and the amount of rotation of the other roll. Calculating means, wherein the command output means outputs to the rotating machine a command to rotate the one rolling roll at a first rotating speed and rotate the other rolling roll at a second rotating speed. Claim 6 adapted to perform
The device for changing the roll cross angle and roll bend force between runs. 8. A means for calculating, over time, a roll bending force to be applied during a change of the roll cross angle using the first rotation speed and the second rotation speed, and the obtained roll bending forces. 8. A running roll cross angle / roll bending force changing device according to claim 7, further comprising means for outputting a command to change the roll bending force applied to the two rolling rolls to the bender.