JP2000015313A - Rolling mill and rolling method - Google Patents

Abstract

(57) Abstract: In a work roll cloth type six-high rolling mill and a rolling method using the same, an axial thrust force generated in a small-diameter work roll is sufficiently reduced. A rolling mill includes an upper / lower work roll (2) whose axes intersect each other, an upper / lower intermediate roll (3), an upper / lower reinforcing roll (4), a lubricant supply device (6), and an axial direction of the work roll (2). Work roll thrust load detecting device 21 for detecting thrust force Fsm, thrust load limit value setting device 22 for setting allowable thrust load Fsf, and work roll crossing angle calculating device for obtaining crossing angle change amount Δθ of work roll 2 23,
A work roll crossing angle changing device 24 that receives the signal and changes the work roll 2 crossing angle θ, a work roll bending force calculating device 25 that obtains a change amount ΔFW of the bending force of the work roll 2 according to the changed crossing angle, A work roll bending force changing device 26 for changing the bending force of the work roll in response to the signal is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet rolling mill, and more particularly, to a rolling mill and a rolling method for rolling by crossing work rolls.

[0002]

2. Description of the Related Art In the field of sheet rolling, improvement of sheet material quality is always required, and various researches and developments have been made to improve sheet material dimensional accuracy. In particular, the quality of the thickness distribution in the width direction directly affects the quality of the sheet material. A rolling mill of a work roll cross type that can intersect and expect a large thickness thickness distribution control ability has been developed.

[0003] In this work roll cross type rolling mill, crossing the work rolls generates an axial thrust force between the work rolls and the sheet material. Also, an axial thrust force is generated. Therefore, it is necessary to reduce these thrust forces by some means.

For example, Mitsubishi Heavy Industries Technical Report Vol. 21, No. 6 (1)
984), the four-high rolling mill disclosed on pages 61 to 67 includes one pair of the upper work roll and the upper reinforcing roll, and the lower work roll and the upper work roll.
By using the lower reinforcement roll as the other pair and using a pair cross method in which each pair is crossed as one,
The generation of thrust force between the work roll and the reinforcing roll is prevented. In the four-high rolling mill disclosed in JP-A-5-50110, a lubricant is supplied from a lubricant supply device between a work roll and a reinforcing roll to reduce a thrust force generated between the work roll and the reinforcing roll. By reducing and further canceling out the reduced thrust force and the thrust force generated between the plate member and the work roll, the thrust force generated on the work roll as a whole is reduced. As described above, when the work roll is crossed to improve the plate thickness distribution control ability,
It is essential to reduce the thrust force.

[0005] The above two prior arts are examples of a four-high rolling mill, and have a relatively large diameter work roll because the work roll is driven.

On the other hand, when rolling a hard material or a thin sheet material, a large-diameter work roll increases the contact area with the sheet material and reduces the contact surface pressure, so that a sufficient amount of reduction cannot be obtained. Is suitable. At this time, in a four-high rolling mill in which the work roll and the reinforcing roll are in direct contact with each other, the diameter between the work roll and the reinforcing roll is too different, and it is not very advantageous from the viewpoint of strength and the like. In many cases, for example, a six-high rolling mill in which an intermediate roll is arranged and which drives the intermediate roll is used. However, in this case, since the rigidity of the work roll is reduced as the diameter of the work roll is reduced, it is necessary to further reduce the axial thrust force.

In a work roll cloth type six-high rolling mill, the following considerations have been made to reduce the axial thrust force.
For example, as disclosed in JP-A-6-31304, an axial thrust force acting on a work roll (thrust force between a work roll and an intermediate roll + thrust force between a work roll and a plate material) is detected and detected. The thrust force between the work roll and the intermediate roll is adjusted by controlling the crossing angle of the intermediate roll according to the thrust force, and the thrust force between the work roll and the intermediate roll acting on the work roll in opposite directions, and the work roll and plate material There are things that cancel out and cancel out the thrust force between them.

[0008]

However, the six-high rolling mill disclosed in Japanese Patent Application Laid-Open No. 6-31304 has a problem that the thrust force generated on the work roll during rolling cannot be sufficiently reduced. This will be described with reference to FIGS.

FIGS. 17 and 18 show the thrust force generated on the work rolls in the four-high rolling mill of the work roll cloth type. FIG. 17 shows the thrust force between the work rolls and the reinforcing rolls, and FIG. 4 shows an example of a characteristic of a thrust force between plate materials. The vertical axis represents the thrust coefficient μ obtained by dividing the generated thrust force in the roll axis direction by the rolling load. The horizontal axis represents μw and μe in FIG.
Is the relative intersection angle θ1 between the axes of the work rolls and the reinforcing rolls, and μp in FIG. 18 is the intersection angle θ2 of one work roll with respect to a line perpendicular to the rolling direction. Also, in FIG.
Although the thrust force between the reinforcing rolls differs depending on the lubrication method between the rolls, FIG. Shown in μe. In FIG. 18, the thrust coefficient between the work roll and the plate material is indicated by μp. FIGS. 17 and 18 show the case of a four-high rolling mill as an example.
In the case of a six-high rolling mill such as No. 31304, the same can be qualitatively considered by replacing the reinforcing roll with an intermediate roll.

(1) Behavior of Each Thrust Coefficient In FIG. 17, the thrust coefficient μw at the time of water lubrication sharply increases as θ1 becomes larger than 0, and θ1 ≒ 0.14.
Μw 度 20 [%] at [degrees], μw at θ1 ≒ 0.38 [degrees]
Μw ≒ 30 at ≒ 26.8 [%], θ1 ≒ 0.79 [degrees]
Reaches [%]. Further, the thrust coefficient μe during emulsion lubrication increases when θ1 becomes larger than 0, and θ1 ≒ 0.0.
1, μe ≒ 6.7 [%], but thereafter, it is almost flat even if θ1 increases, and θ1 ≒ 1.2
Even in [degree], μe ≒ 8 [%]. On the other hand, in FIG. 18, the thrust coefficient μp between the work roll and the plate material increases in proportion to the value of θ2, and μp when θ2 ≒ 0.5 [degree].
Μp ≒ 7.4 at 3.7 [%], θ2 ≒ 1.0 [degree]
[%].

(2) Principle of Thrust Force Reduction As described above, in a six-high rolling mill using small-diameter work rolls, it is essential to sufficiently reduce the axial thrust force. Control is performed so that the thrust force between the work roll and the intermediate roll and the thrust force between the work roll and the plate material are made substantially equal to each other to cancel each other. That is, FIG. 17 and FIG.
When water lubrication is performed, μw and μp
When emulsion lubrication is performed, μe and μp must be set to substantially equal values.

Here, in Japanese Patent Application Laid-Open No. Hei 6-31304, both the intermediate roll and the work roll are crossed, but the cross angle of the work roll is fixed and the cross angle of the intermediate roll is variable.
The variable intermediate roll crossing angle is adjusted to reduce the work roll thrust force. Therefore, μ
p is determined at a certain point in FIG. 18, and the intermediate roll crossing angle is adjusted to change θ2 so that μw or μe in FIG. 17 becomes as equal as possible to the value of μp.

(2-a) Water lubrication However, first, in the case of water lubrication, FIGS.
8 clearly shows that the characteristic line of μw and the characteristic line of μp are too wide, and the thrust force between the work roll and the sheet material is set at any point on the characteristic line of μp (the work roll). Even if the intersection angle is fixed, a normal intersection angle range (for example, θ) used to improve the controllability of the thickness distribution is used.
(1 ≧ 0.2 [degree]), the thrust force between the work roll and the intermediate roll is much larger, so that an excessive thrust force is generated in the work roll. With such an excessive thrust force, the strength of the chocks of the ordinary work rolls is insufficient, and the bearings in the chocks may be damaged. If a chock or bearing capable of withstanding such an excessive thrust force is provided, it must be enormous and the equipment becomes large.

Conversely, if the thrust force between the work roll and the intermediate roll is forced to be equal to the thrust force between the work roll and the sheet material, the intersection angle of the intermediate roll is made substantially equal to the angle formed by the work roll. The relative crossing angle θ1 ロ ー ル 0 [degree] between the intermediate roll and the work roll is set to be close to 0 °. As described above, the characteristic line of μw is θ1 ≦ 0.5.
Up to the vicinity of [degree], it increases very sensitively to the increase of θ1, so that a slight change of θ1 greatly changes μw. Therefore, within this range, the desired relative intersection angle θ1
In order to obtain, it is necessary to control the intersection angle with a considerably high accuracy. Here, in general, a roll of a rolling mill itself has a property of being elastically deformed by a load applied to the roll itself, and the diameter of the roll changes due to wear with use. In addition, there is usually a backlash between the roll supporting chocks and the roll and also in the bearing itself. For this reason, there is a certain limit in the accuracy of the control of the crossing angle, and at present, it is difficult to perform a high-precision crossing angle control that can respond to the sensitive behavior of μw up to about θ1 ≦ 0.5 [degree].

(2-b) Emulsion Lubrication On the other hand, when lubrication is performed using an emulsion, as shown in FIGS. 17 and 18, the difference between the characteristic line of μe and the characteristic line of μp is larger than that in the case of water lubrication. Becomes smaller. However,
As described above, μe is almost flat at θ1 ≧ 0.1 even when θ1 increases, so that the normal intersection angle range (for example, θe) used to improve the controllability of the plate thickness distribution is used.
1 ≧ 0.2 [degree]), except for the case where θ1 ≒ 1.0, the work roll / plate material is set at any point on the characteristic line of μp, regardless of the thrust force between the work roll and the plate material. The difference between the thrust force between the work rolls and the thrust force between the work roll and the intermediate roll cannot be reduced. Therefore, the reduction of the thrust force generated in the work roll is not sufficient. Conversely, as in the above (2-a), if the thrust force between the work roll and the intermediate roll is forced to be equal to the thrust force between the work roll and the plate material, the relative intersection angle θ1 ≦ the intermediate roll and the work roll forms. The characteristic line of μe is very sensitive to the increase of θ1 up to around θ1 ≦ 0.1 [degree]. In order to obtain the intersection angle θ1, it is necessary to perform a highly accurate intersection angle control, which is difficult at present.

The work roll intersection angle θ 2 ≒ 1.0
[Degree], if it is set in the vicinity, μp ≒ 7.4
[%], The crossing angle of the intermediate roll is controlled to control the relative crossing angle θ1 ≒ 0.1 of the working roll and the intermediate roll.
１．２1.2 [degrees], the thrust coefficient μe between the work roll and the plate material can be set to ≒ 6.7-8 [%].
And μe can be made relatively small. However, other work roll crossing angles θ2 << 1.0
When [degree] or θ2 >> 1.0 [degree], the value of μe hardly changes even if the crossing angle of the intermediate roll is controlled to change the relative crossing angle θ1. Cannot be made sufficiently small.

(3) Problems As described above, Japanese Unexamined Patent Application Publication No.
Since a high-precision intersection angle control is required in a high-speed rolling mill and it is actually difficult to realize it, the thrust force of a work roll cannot be sufficiently reduced after all. Therefore, the diameter of the work roll cannot be reduced.

An object of the present invention is to sufficiently reduce axial thrust force generated in a small-diameter work roll in a work roll cloth type six-high rolling mill and a rolling method using the same.

[0019]

(1) In order to achieve the above object, the present invention provides a pair of upper and lower work rolls, a pair of upper and lower intermediate rolls respectively supporting these work rolls, A pair of upper and lower reinforcing rolls respectively supporting an intermediate roll, a lubricant supply unit for supplying a lubricant for lubricating between the work roll and the intermediate roll, and a work roll for applying a bending force to the work roll In a rolling mill having a bending means and a work roll inclining means for inclining the pair of work rolls in a substantially horizontal plane so that their axes intersect with each other and intersect with the pair of intermediate rolls, respectively. A work roll thrust load detecting means for detecting an axial thrust force of the work roll, and a detection value of the work roll thrust load detecting means being not more than a predetermined limit value. A tilt control means for controlling the work rolls tilting means to so that, depending on the control to the work roll inclining means by the tilt control means are provided and a bending control unit which controls the work roll bending means. The axial thrust force generated in the work roll of the six-high rolling mill includes a thrust force generated between the work roll and the intermediate roll, and a thrust force generated between the plate and the work roll. Among these, the thrust force generated between the work roll and the intermediate roll is a small area (for example, θ10 ≦ 0.1) of the relative intersection angle θ10 formed between the work roll and the intermediate roll.
Except for (degree), it is almost constant regardless of the value of the relative intersection angle θ10. On the other hand, the thrust force generated between the plate member and the work roll monotonically increases as the value of the intersection angle θ20 of the work roll increases. Therefore, in the present invention, the work roll thrust load detecting means detects the axial thrust force of the work roll, and based on the detected thrust force, the inclination control means controls the work roll inclining means to control the intersection angle of the work roll. Is adjusted so that the detected thrust force is equal to or less than a predetermined limit value. That is, first, the thrust force generated between the plate member and the work roll is increased or decreased by adjusting the intersection angle θ20 of the work roll. On the other hand, at this time, the adjustment of the crossing angle θ20 also changes the relative crossing angle θ10 formed between the work roll and the intermediate roll, but as described above, except for a small area of θ10, regardless of the magnitude of θ10, The thrust force generated between the rolls is almost constant. This makes it possible to increase or decrease only the thrust force generated between the sheet material and the work roll by adjusting the crossing angle θ20 of the work roll, so that the thrust force generated between the work roll and the intermediate roll is always reduced. Force, so that these two thrust forces can be canceled. Therefore, the thrust force generated in the work roll can be sufficiently reduced, and the diameter of the work roll can be easily reduced. In this case, in the control of the crossing angle of the work rolls, as described above, the thrust force between the work rolls and the intermediate rolls is related to the change in θ10 in a region where the relative crossing angle θ10 between the work rolls and the intermediate rolls is not small. The work roll thrust force is reduced by using the property that the work roll becomes substantially constant. That is, there is no need to perform very high-precision control in a region where the relative intersection angle θ10 between the work roll and the intermediate roll is small as in the conventional structure in which the intersection angle of the intermediate roll is changed based on the detected thrust force value. . Therefore, it can be easily realized even with an actual rolling mill. Also, a change in the crossing angle of the work rolls for reducing the thrust force may cause a change in the sheet crown.However, the work roll bending means is adjusted by the bending control means according to the control of the inclination control means, and the work roll is appropriately adjusted. By applying the bending force, a change in the sheet crown due to a change in the crossing angle of the work roll can be eliminated, and the sheet material quality can be kept good.

(2) In the above (1), preferably,
The inclination control unit is an intersection angle change amount calculation unit that calculates an intersection angle change amount of the work roll according to the detection value of the work roll thrust load detection unit and the predetermined limit value. The roll inclining means changes the crossing angle of the work roll according to the crossing angle change amount, and the bending control means calculates a first bending force change amount of the work roll according to the crossing angle change amount. First
, Wherein the work roll bending means changes the bending force of the work roll according to the first bending force change amount.

(3) In the above (2), further preferably, there is further provided a thrust load setting means for externally setting and inputting an allowable work roll thrust load as the predetermined limit value.

(4) In the above (1), preferably, the apparatus further comprises a crown setting means for externally setting and inputting an allowable crown, and the inclination control means comprises:
In accordance with the value detected by the work roll thrust load detection means and the predetermined limit value, is a cross angle change amount calculation means for calculating the cross angle change amount of the work roll, the work roll inclination means, Changing the crossing angle of the work roll according to the crossing angle change amount, the bending control means,
A second bending force change amount calculating unit that calculates a second bending force change amount of the work roll according to the set value of the crown setting unit and the crossing angle change amount, wherein the work roll bending unit includes: And changing the bending force of the work roll according to the second bending force change amount.

(5) In the above (1), preferably, the work roll further includes an intermediate roll bending means for applying a bending force to the intermediate roll, and the bending control means is provided with the work roll by the inclination control means. The work roll bending means and the intermediate roll bending means are controlled according to the control of the tilting means.

(6) In the above (1), preferably, the intermediate roll shift means for shifting the intermediate roll in the axial direction, and the intermediate roll shift according to the control of the work roll tilting means by the tilt control means. Shift control means for controlling the means.

(7) In the above (1), preferably, an intermediate roll bending means for applying a bending force to the intermediate roll, an intermediate roll shift means for shifting the intermediate roll in the axial direction, and the inclination control means Further comprising shift control means for controlling the intermediate roll shift means in accordance with control of the work roll inclining means, and wherein the bending control means responds to control of the work roll inclining means by the inclination control means. And controlling the work roll bending means and the intermediate roll bending means.

(8) In the above (1), preferably, the axes of the pair of intermediate rolls intersect with the axes of the pair of reinforcing rolls, and the axes of the intermediate rolls intersect with each other. As described above, an intermediate roll crossing angle detection unit that is disposed to be inclined in a substantially horizontal plane and that detects the crossing angle of the pair of intermediate rolls is further provided, and the bending control unit includes the tilt control unit. The work roll bending means is controlled in accordance with the control of the work roll inclination means by the means and the detection result of the intermediate roll crossing angle detection means.

(9) In (1) above, preferably, the axes of the pair of intermediate rolls intersect with the axes of the pair of reinforcing rolls, and the axes of the intermediate rolls intersect with each other. As described above, an intermediate roll crossing angle detecting unit that is arranged to be inclined in a substantially horizontal plane, and detects the crossing angle of the intermediate rolls, and an intermediate roll bending unit that applies a bending force to the intermediate rolls. And a bending control unit that controls the work roll tilting unit by the tilt control unit and a detection result of the intermediate roll crossing angle detection unit. Means and control. (10) In order to achieve the above object, the present invention provides a pair of upper and lower work rolls, a pair of upper and lower intermediate rolls respectively supporting these work rolls, and an upper and lower pair respectively supporting these intermediate rolls. Using a rolling mill having a pair of reinforcing rolls, supplying a lubricant for lubricating between the work rolls and the intermediate rolls, applying a bending force to the work rolls, the pair of work rolls, A first procedure for detecting an axial thrust force of the work roll in a rolling method in which a plate is rolled while being inclined in a substantially horizontal plane so that axes of the work cross each other and each of the pair of intermediate rolls cross each other. A second procedure for inclining the work roll such that the detected value is equal to or less than a predetermined limit value, and a third procedure for applying a bending force to the work roll in accordance with the inclination.
Procedure.

(11) In the above (10), preferably, the second procedure is performed in accordance with the axial thrust force of the work roll detected in the first procedure and the predetermined limit value. The third step is a step of calculating an intersection angle change amount of the roll and changing an intersection angle of the work roll according to the intersection angle change amount. This is a procedure of calculating a first bending force change amount and changing the bending force of the work roll according to the first bending force change amount.

(12) In the above (11), more preferably, an allowable work roll thrust load is externally set and input as the predetermined limit value.

(13) In the above (10), preferably, there is further provided a fourth procedure for setting and inputting an allowable crown from the outside, and the second procedure is the same as the first procedure. The intersection angle change amount of the work roll is calculated according to the detected axial thrust force of the work roll and the predetermined limit value, and the intersection angle of the work roll is changed according to the intersection angle change amount. The third procedure calculates a second bending force change amount of the work roll according to the set value set and input in the fourth procedure and the intersection angle change amount, and calculates the second bending force change amount of the work roll. It is a procedure for changing the bending force of the work roll according to the bending force change amount.

(14) In the above (10), preferably, the third step is a step of applying a bending force to the work roll and the intermediate roll in accordance with the inclination in the second step. It is.

(15) In the above (10), preferably, the method further includes a fifth step of shifting the intermediate roll in the axial direction according to the inclination in the second step.

(16) In the above (10), preferably, the third step is a step of applying a bending force to the work roll and the intermediate roll in accordance with the inclination in the second step. And a fifth step of shifting the intermediate roll in the axial direction according to the inclination in the second step.

(17) In the above (10), preferably, the pair of intermediate rolls intersects the axes of the pair of reinforcing rolls, and the axes of the intermediate rolls cross each other. The method further includes a sixth procedure of rolling the roll by arranging it in an inclined manner in a substantially horizontal plane, and detecting an intersection angle between the pair of intermediate rolls, and wherein the third procedure is the third procedure. This is a procedure in which a bending force is applied to the work roll in accordance with the inclination in the second procedure and the detection result in the sixth procedure.

(18) In the above (10), preferably, the pair of intermediate rolls are arranged such that their axes intersect with the axes of the pair of reinforcing rolls, respectively, and the axes of the intermediate rolls intersect with each other. A sixth procedure of rolling while being arranged at an angle in a substantially horizontal plane, and detecting an intersection angle of the pair of intermediate rolls, and wherein the third procedure is the second procedure. And applying a bending force to the work roll and the intermediate roll in accordance with the inclination in the procedure and the detection result in the sixth procedure.

[0036]

Embodiments of the present invention will be described below with reference to the drawings.

A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to the present embodiment, and FIG. It is a conceptual perspective view showing.

In FIGS. 1 and 2, the rolling mill according to the present embodiment comprises a pair of upper and lower work rolls 2, 2, a pair of upper and lower intermediate rolls 3, 3 supporting these work rolls, respectively, and The upper and lower reinforcing rolls 4, 4 for supporting the intermediate rolls 3, 3, respectively, are provided on the rolling stand 5,
The reinforcing rolls 4 and 4 are configured such that their axes do not incline in the horizontal plane, and the work rolls 2 and 2 are inclined such that their axes intersect each other in the horizontal plane and intersect with the axes of the intermediate rolls 3 and 3, respectively. A lubricant supply device 6 for supplying a lubricant for lubricating between the work rolls 2, 2 and the intermediate rolls 3, 3 is provided. Also,
The rolling mill includes a work roll thrust load detecting device 21 for detecting an axial thrust force Fsm of the work roll 2, a thrust load limit value setting device 22 for setting an allowable thrust load Fsf, and a thrust load limit value setting device. A work roll crossing angle calculation device 23 and a work roll crossing angle calculation device 23 which compare and calculate the set value from 22 and the measured value of the thrust load to obtain the change amount Δθ of the crossing angle (cross angle) of the work roll 2. And a work roll crossing angle changing device 24 for changing the crossing angle θ of the work roll 2 in response to a signal from the work roll 2 and a change amount ΔFW of the bending force of the work roll 2 in response to the signal from the crossing angle calculating device 23. Work roll bending force calculation device 25 and work for changing the bending force of work roll 2 in response to a signal from work roll bending force calculation device 25 A roll bending force changing device 26 is provided.

In the above description, the lubricant supply device 6
Constitutes a lubricant supply means for supplying a lubricant for lubricating between the work roll and the intermediate roll, and the work roll bending changing device 26 constitutes a work roll bending means for applying a bending force to the work roll, The work roll crossing angle changing device 24 constitutes a work roll inclining means for inclining a pair of work rolls in a substantially horizontal plane such that their axes cross each other and cross each of the pair of intermediate rolls. Further, the work roll thrust load detecting device 21 constitutes a work roll thrust load detecting means for detecting an axial thrust force of the work roll, and the thrust load limit value setting device 22 sets an allowable work as a predetermined limit value. A thrust load setting means for externally setting and inputting a roll thrust load is provided. Further, the intersection angle calculation device 2
3 is a cross-angle change amount calculating means for calculating a cross-angle change amount of the work roll according to the detection value of the work roll thrust load detecting means and a predetermined limit value, and the detection of the work roll thrust load detecting means. A tilt control means for controlling the work roll tilt means so that the value is equal to or less than a predetermined limit value is also configured. Also, the work roll bending force calculating device 25
Constitutes a first bending force change amount calculating means for calculating a first bending force change amount of the work roll in accordance with the intersection angle change amount, and performs a work in accordance with the control of the work roll inclining means by the inclination control means. Bending control means for controlling the roll bending means is also configured.

In the above configuration, the axial thrust load of the work roll 2 is measured by the work roll thrust load detecting device 21, and the work roll crossing angle calculating device 23 sets and inputs the thrust load limit value setting device 22 from outside in advance. The calculated value is compared with the value of the thrust load measured by the work roll thrust load detecting device 21.

The comparison calculation processing in the work roll crossing angle calculation device 23 is as follows. By subtracting the measured thrust load value Fsm from the set value Fsf of the thrust load limit value setting device 22, the thrust force ΔFs to be corrected can be obtained.
If the measured thrust force Fsm is smaller than the set value Fsf, the following processing is unnecessary and no particular processing is performed. The thrust force Fs generated on the work roll 2 is expressed as follows using the thrust force Fr generated between the work roll 2 and the intermediate roll 3 and the thrust force Fp generated between the plate material and the work roll 2. Fs = Fr−Fp (1) Fr and Fp are the rolling load Pr and the thrust coefficient μe at the time of emulsion lubrication between the work roll 2 and the intermediate roll 3.
(See FIG. 17 described above) and the thrust coefficient μp (same as above) between the plate material and the work roll 2 are expressed as follows. Fr = μe · Pr (2) Fp = μp · Pr (3) At this time, examples of the characteristics of μe and μp are shown in FIGS. 3 and 4. FIGS. 3 and 4 substantially correspond to FIGS. 17 and 18 described above. 3 shows an example of the characteristic of the thrust force between the work roll and the intermediate roll, and FIG. 4 shows an example of the characteristic of the thrust force between the work roll and the plate material. The relative intersection angle θ10 between the axes is taken, and in FIG. 4, the intersection angle θ of one work roll with respect to a line perpendicular to the rolling direction is shown. In FIG. 3, as in FIG. 17, the thrust coefficient μe
Increases when θ1 becomes larger than 0, and θ10 ≒ 0.1
In [degrees], μe ≒ 6.7 [%], and after that, it is almost flat even if θ10 increases. On the other hand, in FIG. 4, similarly to FIG. 18, the thrust coefficient μp between the work roll and the plate material increases in proportion to the value of θ,
μp ≒ 3.7 [%] at θ ≒ 0.5 [degree], θ ≒ 1.0
In [degrees], μp ≒ 7.4 [%]. As described above, since the intersection angle θ between the plate and the work roll 2 is substantially proportional to the thrust coefficient μp, it can be expressed as follows. μp = Cp · θ + D (4) where Cp is a proportionality constant. Here, in the present embodiment, the control is always performed in a region near θ1 ≧ 0.1 [degree] in FIG. I will do it. In this case, the change Δ in the work roll intersection angle
Since the change in μe due to θ is negligible, the relationship between the change Δθs in the crossing angle of the work roll and the change ΔFs in the thrust force can be approximately expressed as follows. ΔFs ≒ −Pr · Cp · Δθ (5) From equation (5), the change Δθ of the work roll intersection angle to be corrected with respect to the thrust force ΔFs to be corrected is obtained as follows. Δθ = −ΔFs / (Pr · Cp) (6) The work roll crossing angle changing device 24 receives a signal from the work roll crossing angle calculating device 23 (the change Δθ of the work roll crossing angle) to obtain the work roll 2. Is changed.

The control performed by the work roll crossing angle calculating device 23 and the work roll crossing angle changing device 24 will be specifically described with an example. For example, first, the crossing angle (variable) of the work roll 2 with respect to a line perpendicular to the rolling direction is described. ) Is θ = 0.
It is assumed that the crossing angle (fixed) of the intermediate roll with respect to a line perpendicular to the rolling direction is θA = 1.2 [degrees]. In this case, the relative intersection angle between the work roll 2 and the intermediate roll 3 is θ
Since 10 = 0.5 [degree], it is determined from FIG.
-The thrust coefficient μe between the intermediate rolls 3 is 6.9 [%]. Further, since θ = 0.7 [degree], from FIG.
Thrust coefficient between work roll 2 and plate material μp ≒ 5.1
[%]. Thereby, 1.8 of these μp and μe is obtained.
Based on the difference of [%], Fs =
A thrust force Fs having a magnitude of Pr (μe-μp) is first generated on the work roll 2. In the present embodiment, in such a case, control is performed such that the value of μe−μp is reduced and Fs is reduced. That is, for example, Δθ = 0.3 [degree]
And the intersection angle of the work roll 2 is set to θ ≒ 1.0 [degree]. Since the intersection angle θA of the intermediate roll 3 is 1.2 [degrees], the relative intersection angle between the work roll 2 and the intermediate roll 3 is θ10.
= 0.2 [degrees]. At this time, according to FIG. 3, the thrust coefficient between the work roll 2 and the intermediate roll 3 is μe ≒ 6.9.
[%], But from FIG.
The thrust coefficient between the plate materials is μp ≒ 7.25 [%],
The difference between μp and μe can be reduced to 0.35 [%]. Therefore, the magnitude of the thrust force Fs = Pr (μe−μp) generated on the work roll 2 can be sufficiently reduced.

The work roll bending force calculator 25 receives the signal (the change Δθ in the work roll crossing angle) from the work roll crossing angle calculator 23 and receives the signal from the work roll 2.
Of the bending force change ΔFW of the bending force. This is performed as follows. The change ΔCh of the sheet crown of the sheet material,
The change amount Δθ of the intersection angle of the work roll 2 and the work roll 2
Is generally expressed by the following equation.

ΔCh = (Ch / θ) · Δθ + (Ch / FW) · ΔFW (7) where Ch is the plate crown, θ is the intersection angle of the work roll 2, and FW is the bending force of the work roll 2. . The coefficient (Ch / θ) and the coefficient (Ch / FW) may be obtained in advance by calculation or experiment. If ΔCh = 0 in equation (7), the following equation is obtained. .DELTA.FW =-(Ch / .theta.). Multidot..theta ./ (Ch / FW) (8) Expression (8) is an equivalent work roll 2 for canceling the sheet crown change due to the change .DELTA..theta.
In the bending force change amount ΔFW.

The work roll bending force changing device 26 changes the bending force of the work roll 2 in response to a signal (the work roll bending force change amount ΔFW) from the work roll bending force calculation device 25. Thereby, the sheet crown change due to the change amount Δθ of the intersection angle of the work roll 2 is eliminated, and the sheet material quality is kept good.

As described above, according to this embodiment, by adjusting the intersection angle θ of the work roll 2 in a region where the relative intersection angle θ10 of the work roll 2 and the intermediate roll 3 does not become very small, the work with the plate material can be performed. The thrust force Fp = μp · Pr generated between the roll 2 is increased or decreased. Thereby, the thrust force Fr generated between the work roll 2 and the intermediate roll 3
Only the thrust force Fp between the plate material and the work roll 2 can be increased / decreased without increasing or decreasing the thrust force Fp.
Between the thrust force Fr generated between the two
The two thrust forces Fp and Fr can be canceled. Therefore, the thrust force Fs generated on the work roll 2
Can be sufficiently reduced, and the diameter of the work roll 2 can be easily reduced. As a result, the thickness of the roll cloth is restricted due to an increase in the thrust force, and the thickness distribution becomes non-uniform. The plate material can be rolled stably. In this case, in the control of the intersection angle θ of the work roll 2 at this time, as described above, the thrust force between the work roll 2 and the intermediate roll 3 is set in a region where the relative intersection angle θ10 between the work roll 2 and the intermediate roll 3 is not small. F
The thrust force Fs of the work roll 2 is reduced by using the property that r becomes substantially constant regardless of the change of θ10. That is, there is no need to perform very high-precision control in a region where the relative intersection angle between the work roll and the intermediate roll is small, as in the conventional structure in which the intersection angle of the intermediate roll is changed based on the detected thrust force value. Therefore, it can be easily realized even with an actual rolling mill. Further, even if a change in the sheet crown occurs due to a change in the intersection angle θ of the work roll 2 for reducing the thrust force Fs, the work roll bending force calculating device 25 applies a force to the work roll 2 via the work roll bending force changing device 26. By applying the bending force represented by the equation (8), a change in the sheet crown due to a change in the intersection angle θ of the work roll 2 can be eliminated, and the sheet material quality can be kept good.

A second embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to the present embodiment, and FIG. It is a conceptual perspective view showing. First
The same reference numerals are given to the same parts as those of the embodiment, and the description is omitted.

In FIGS. 5 and 6, the difference between the rolling mill according to the present embodiment and the rolling mill according to the first embodiment is as follows.
Instead of the work roll bending force calculation device 25, a bending force calculation device 51 for obtaining the change amount of the bending force of the intermediate roll 3 and the change amount of the bending force of the work roll 2 according to the change amount of the intersection angle of the work roll 2 is provided. Provided,
Further, an intermediate roll bending force changing device 32 that receives a signal from the bending force calculation device 51 and changes the bending force of the intermediate roll 3 is provided. Other configurations are almost the same as those of the first embodiment. The intermediate roll bending force changing device 32 constitutes an intermediate roll bending means for applying a bending force to the intermediate roll.

In the above configuration, first, similarly to the first embodiment, the axial thrust load of the work roll 2 is measured by the work roll thrust load detecting device 21, and the measured thrust load value and the thrust load limit value are measured. Setting device 22
Then, the work roll intersection angle calculation device 23 performs a comparison calculation with a value set in advance. The work roll crossing angle changing device 24 receives the signal from the work roll crossing angle calculating device 23 and changes the crossing angle of the work roll 2. This corrects the excessive thrust force.

On the other hand, the bending force calculating device 51 outputs a signal from the work roll intersection angle calculating device 23 (work roll 2).
), The bending force change amount ΔFI of the intermediate roll 3 and the bending force change amount ΔFW of the work roll 2 are determined. This is performed as follows. Assuming that the change of the sheet crown at two points in the width direction of the sheet is ΔCh1 and ΔCh2, respectively,
Is generally expressed by the following equation: .DELTA..theta., The amount of change in bending force of the intermediate roll 3, and the amount of change .DELTA.FW in bending force of the work roll 2. ΔCh1 = (Ch1 / θ) Δθ + (Ch1 / FI) ΔFI + (Ch1 / FW) ΔFW (9) ΔCh2 = (Ch2 / θ) Δθ + (Ch2 / FI) ΔFI + (Ch2 / FW) ΔFW (10) The coefficients in parentheses may be obtained in advance by calculation or experiment. In these equations (9) and (10), Δ
If Ch1 = ΔCh2 = 0, the following equation is obtained. − (Ch1 / θ) Δθ = (Ch1 / FI) ΔFI + (Ch1 / FW) ΔFW (11) − (Ch2 / θ) Δθ = (Ch2 / FI) ΔFI + (Ch2 / FW) ΔFW (12) , (11) and (12) give ΔFI,
Since this is a binary simultaneous equation with ΔFW as an unknown, it can be easily solved, and ΔFI and ΔFW can be easily obtained. These are equivalent bending force change amount ΔFI of the intermediate roll 3 and bending force change amount ΔFW of the work roll 2 for canceling the sheet crown change due to the change amount Δθ of the crossing angle of the work roll 2.
Is represented.

The intermediate roll bending force changing device 32 receives the signal (bending force change amount ΔFI of the intermediate roll 3) from the bending force calculating device 51, and changes the bending force of the intermediate roll 3. The work roll bending force changing device 26 changes the bending force of the work roll 2 in response to a signal (bending force change amount ΔFW of the work roll 2) from the bending force calculation device 51. As a result, it is possible to eliminate the sheet crown change due to the change amount Δθ of the crossing angle of the work roll 2 and maintain the sheet material quality in a good condition.

According to this embodiment, the same effects as those of the first embodiment can be obtained. Further, since the change amount of the sheet crown at two points in the width direction of the sheet material can be set to ΔCh1 and ΔCh2 = 0, the sheet material quality can be further kept good.

A third embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to the present embodiment, and FIG. It is a conceptual perspective view showing. First
The same reference numerals are given to portions common to the second embodiment and the second embodiment, and the description is omitted.

7 and 8, the difference between the rolling mill according to the present embodiment and the rolling mill according to the first embodiment is as follows.
Instead of the work roll bending force calculation device 25, the intermediate roll axial position and work roll for obtaining the axial position of the intermediate roll 3 and the change amount of the bending force of the work roll 2 according to the change amount of the intersection angle of the work roll 2. A bending force calculating device 52 is provided, and an intermediate roll axial position changing device 33 for changing the axial position of the intermediate roll 3 in response to a signal from the intermediate roll axial position / work roll bending force calculating device 52 is provided. It is. Other configurations are almost the same as those of the first embodiment. Note that the intermediate roll axial position changing device 33 constitutes an intermediate roll shift unit that shifts the intermediate roll 3 in the axial direction. Further, the intermediate roll axial position / work roll bending force calculating device 52 includes a bending control means for controlling the work roll bending means in accordance with the control of the work roll inclination means by the tilt control means, and a work roll inclination by the inclination control means. And a shift control means for controlling the intermediate roll shift means in accordance with the control of the means.

In the above configuration, first, the first and second
Similarly to the embodiment, the axial thrust load of the work roll 2 is measured by the work roll thrust load detection device 21, and the measured thrust load value and the value set in advance by the thrust load limit value setting device 22 are used. Are compared and calculated by the work roll crossing angle calculation device 23. The work roll crossing angle changing device 24 includes a work roll crossing angle calculating device 23.
The intersection angle of the work roll 2 is changed in response to the signal from.
This corrects the excessive thrust force.

On the other hand, the intermediate roll axial position / work roll bending force calculating device 52 receives a signal from the work roll crossing angle calculating device 23 and calculates the axial position change amount ΔS of the intermediate roll 3 and the bending force of the work roll 2. Change amount Δ
Find FW. This is performed as follows.

Assuming that the changes of the sheet crown at two points in the width direction of the sheet are ΔCh 1 and ΔCh 2, respectively, the change Δθ of the intersection angle of the work roll 2, the axial position change amount ΔS of the intermediate roll 3, and the work roll The relationship of the bending force change amount ΔFW of 2 is generally represented by the following equation. ΔCh1 = (Ch1 / θ) Δθ + (Ch1 / S) ΔS + (Ch1 / FW) ΔFW (13) ΔCh2 = (Ch2 / θ) Δθ + (Ch2 / S) ΔS + (Ch2 / FW) ΔFW (14) The coefficients in parentheses may be obtained in advance by calculation or experiment. In these equations (13) and (14), Δ
If Ch1 = ΔCh2 = 0, the following equation is obtained. − (Ch1 / θ) Δθ = (Ch1 / S) ΔS + (Ch1 / FW) ΔFW (15) − (Ch2 / θ) Δθ = (Ch2 / S) ΔS + (Ch2 / FW) ΔFW (16) , (15) and (16) are given by ΔS, Δ
Since it is a binary simultaneous equation in which FW is an unknown number, it can be easily solved, and ΔS and ΔFW can be easily obtained. These are equivalent axial position change amounts ΔS of the intermediate roll 3 for canceling the sheet crown change due to the change amount Δθ of the intersection angle of the work roll 2.
And the bending force change amount ΔFW of the work roll 2.

The intermediate roll axial position changing device 33 receives a signal (the axial position change amount ΔS of the intermediate roll 3) from the intermediate roll axial position / work roll bending force calculating device 52 and receives the intermediate roll. 3. Change the axial position of 3. The work roll bending force changing device 26 changes the bending force of the work roll 2 in response to a signal from the intermediate roll axial position / work roll bending force calculation device 52 (bending force change amount ΔFW of the work roll 2). This makes it possible to eliminate the change of the sheet crown due to the change Δθ of the crossing angle of the work roll 2 and to maintain the good sheet material quality.

According to this embodiment, the same effect as that of the first embodiment can be obtained. Further, since the change amount of the sheet crown at two points in the width direction of the sheet material can be set to ΔCh1 and ΔCh2 = 0, the sheet material quality can be further kept good.

FIGS. 9 and 10 show a fourth embodiment of the present invention.
This will be described below. This embodiment is an embodiment in which the second embodiment and the third embodiment are combined. FIG. 9 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to the present embodiment.
FIG. 1 is a conceptual perspective view illustrating a main structure of a work roll cloth type six-high rolling mill according to an embodiment. Portions common to the first to third embodiments are denoted by the same reference numerals, and description thereof is omitted.

In FIGS. 9 and 10, the difference between the rolling mill according to the present embodiment and the rolling mill according to the first embodiment is that
The axial position of the intermediate roll 3 according to the change amount of the intersection angle of the work roll 2, the change amount of the bending force of the intermediate roll 3,
And an intermediate roll axial position / bending force calculating device 53 for calculating the amount of change in the bending force of the work roll 2. Further, the intermediate roll axial position / bending force calculating device 53 receives a signal from the intermediate roll axial position / bending force calculating device 53. An intermediate roll axial position changing device 33 for changing the position and an intermediate roll bending force changing device 32 for changing the bending force of the intermediate roll 3 are provided. Other configurations are almost the same as those of the first embodiment. Incidentally, the intermediate roll axial position / bending force calculating device 53 responds to the control of the work roll inclining means by the inclining control means,
It comprises both a bending control means for controlling the work roll bending means and the intermediate roll bending means, and a shift control means for controlling the intermediate roll shift means in accordance with the control of the work roll tilting means by the inclination control means.

In the above configuration, first, similarly to the first to third embodiments, the axial thrust load of the work roll 2 is measured by the work roll thrust load detecting device 21, and the measured thrust load value is compared with the measured thrust load. The work roll crossing angle calculating device 23 compares and calculates a value previously set by the thrust load limit value setting device 22. The work roll crossing angle changing device 24 includes a work roll crossing angle calculating device 23.
(The change amount Δθ of the crossing angle of the work roll 2) from the control unit 2 changes the crossing angle of the work roll 2. This corrects the excessive thrust force.

On the other hand, the intermediate roll axial position / bending force calculating device 53 receives a signal from the work roll crossing angle calculating device 23 and changes the axial position change amount Δ of the intermediate roll 3.
S and the bending force change amount ΔFW of the work roll 2 are obtained. This is performed as follows.

Assuming that the changes of the sheet crown at certain three points in the width direction of the sheet are ΔCh1, ΔCh2, and ΔCh3, respectively, the change Δθ of the intersection angle of the work roll 2, the axial position change amount ΔS of the intermediate roll 3, The relationship between the bending force change amount ΔFI of the intermediate roll 3 and the bending force change amount ΔFW of the work roll 2 is generally represented by the following equation. ΔCh1 = (Ch1 / θ) Δθ + (Ch1 / S) ΔS + (Ch1 / FI) ΔFI + (Ch1 / FW) ΔFW (17) ΔCh2 = (Ch2 / θ) Δθ + (Ch2 / S) ΔS + (Ch2 / FI) ) ΔFI + (Ch2 / FW) ΔFW (18) ΔCh3 = (Ch3 / θ) Δθ + (Ch3 / S) ΔS + (Ch3 / FI) ΔFI + (Ch3 / FW) ΔFW (19) However, the coefficient in parentheses is It may be obtained in advance by calculation or experiment. In Equations (17) to (19), ΔC
If h1 = ΔCh2 = ΔCh3 = 0, the following equation is obtained. − (Ch1 / θ) Δθ = (Ch1 / S) ΔS + (Ch1 / FI) ΔFI + (Ch1 / FW) ΔFW (20) − (Ch2 / θ) Δθ = (Ch2 / S) ΔS + (Ch2 / FI) ΔFI + (Ch2 / FW) ΔFW (21) − (Ch3 / θ) Δθ = (Ch3 / S) ΔS + (Ch3 / FI) ΔFI + (Ch3 / FW) ΔFW (22) where (20) Equations (22) are given by ΔS, ΔF
Since it is a ternary simultaneous equation in which I and ΔFW are unknowns, it can be easily solved, and ΔS, ΔFI, and ΔFW can be easily obtained. These are equivalent axial position change amount ΔS of the intermediate roll 3 and bending amount change amount ΔF of the intermediate roll 3 for canceling the sheet crown change due to the change amount Δθ of the crossing angle of the work roll 2.
I and the bending force change amount ΔFW of the work roll 2.

The intermediate roll axial position changing device 33 receives a signal from the intermediate roll axial position / bending force calculating device 53 (the axial position change amount ΔS of the intermediate roll 3), and Change the axial position. In the intermediate roll bending force changing device 32,
A signal from the intermediate roll axial direction position / bending force calculation device 53 (the bending force change amount Δ
FI), the bending force of the intermediate roll 3 is changed. Further, the work roll bending force changing device 26 includes an intermediate roll axial position / bending force calculating device 5.
3, the bending force of the work roll 2 is changed in response to the signal (3) (the bending force change amount .DELTA.FW of the action roll 2). This makes it possible to eliminate a change in the sheet crown due to the change Δθ in the work roll crossing angle and to maintain a good sheet material quality.

According to this embodiment, the same effect as that of the first embodiment can be obtained. In addition, since the change amount of the sheet crown at three points in the width direction of the sheet material can be set to ΔCh1, ΔCh2, and ΔCh3 = 0, the quality of the sheet material can be further improved.

FIG. 11 and FIG. 1 show a fifth embodiment of the present invention.
2 will be described. FIG. 11 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to the present embodiment, and FIG. It is a conceptual perspective view showing. Portions common to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In FIGS. 11 and 12, the rolling mill according to the present embodiment is different from the rolling mill according to the first embodiment in that a pair of intermediate rolls 3 and 3 has a pair of reinforcing rolls 4 whose axes are parallel to each other. 4 so as to intersect each other and the axes of the intermediate rolls 3 and 3 to intersect each other.
It is arranged in an inclined manner in a substantially horizontal plane (however, the crossing angle is fixed), the crossing angle detecting device 34 for detecting the crossing angle of the intermediate rolls 3 is provided, and the work roll bending force calculating device 25 Instead, the work roll bending force calculation device 54 for calculating the change amount of the bending force of the work roll 2 according to the change amount of the intersection angle of the work roll 2 and the cross angle of the intermediate roll 3 detected by the cross angle detection device 34. That is, Other configurations are almost the same as those of the first embodiment. The intersection angle detection device 34 constitutes an intermediate roll intersection angle detection unit that detects an intersection angle between a pair of intermediate rolls.

In the above configuration, first, similarly to the first embodiment, the axial thrust load of the work roll 2 is measured by the work roll thrust load detecting device 21, and the measured thrust load value and the thrust load limit value are measured. Setting device 22
Then, the work roll intersection angle calculation device 23 performs a comparison calculation with a value set in advance. The work roll crossing angle changing device 24 receives the signal from the work roll crossing angle calculating device 23 and changes the crossing angle of the work roll 2. This corrects the excessive thrust force.

On the other hand, in the work roll bending force calculating device 54, the signal from the intermediate roll crossing angle detecting device 34 (crossing angle θI of the intermediate roll 3) and the signal from the work roll crossing angle calculating device 23 (crossing of the work roll 2) Angle change Δ
θ), the bending force change amount ΔFW of the work roll 2 is obtained. This is performed as follows. The change amount of the sheet crown in the width direction of the sheet material is ΔCh, and the work roll 2
Is generally expressed as follows, as shown in the equation (7) of the first embodiment, as well as the change amount Δθ of the intersection angle and the bending force change amount ΔFW of the work roll 2. ΔCh = (Ch / θ) Δθ + (Ch / FW) · ΔFW (23) Here, the coefficient (Ch / θ) and the coefficient (Ch / FW) may be obtained in advance by calculation or experiment. Since the coefficient is a function of the intersection angle θI of the intermediate roll 3, in this embodiment, (Ch / θ) and (Ch / FW)
Is calculated in advance, and the coefficient (Ch / θ) and the coefficient (Ch / FW) may be obtained by substituting the intersection angle θI from the intermediate roll intersection angle detection device 34.
If ΔCh = 0 in equation (23), the following equation similar to equation (8) of the first embodiment can be obtained. .DELTA.FW =-(Ch / .theta.). Multidot..theta ./ (Ch / FW) (24) Expression (24) is an equivalent work roll 2 for canceling a sheet crown change due to a change .DELTA..theta. In the bending force change amount ΔFW.

The work roll bending force changing device 26 receives the signal from the work roll bending force calculation device 54 (the above-mentioned work roll bending force change amount ΔFW) and changes the bending force of the work roll 2. As a result, it is possible to eliminate the sheet crown change due to the change Δθ of the work roll crossing angle and to maintain good sheet material quality.

According to this embodiment, the same effects as those of the first embodiment can be obtained. Further, the coefficient (C
h / θ) and the coefficient (Ch / FW) are obtained by using the crossing angle θI from the intermediate roll crossing angle detecting device 34, whereby control can be performed with simpler calculations.

FIGS. 13 and 1 show a sixth embodiment of the present invention.
4 will be described. FIG. 13 is a front view showing an overall schematic structure of a work roll cloth type six-high rolling mill according to the present embodiment, and FIG. It is a conceptual perspective view showing. Portions common to the fifth embodiment are denoted by the same reference numerals, and description thereof is omitted.

13 and 14, the difference between the rolling mill according to the present embodiment and the rolling mill according to the fifth embodiment is that the work roll bending force calculating device 54
A bending force calculating device 55 for calculating the amount of change in the bending force of the intermediate roll 3 and the amount of change in the bending force of the work roll 2 according to the amount of change in the intersection angle of the work roll 2 is provided. An intermediate roll bending force changing device 32 for changing the bending force of the intermediate roll 3 in response to a signal is provided. Other configurations are almost the same as those of the fifth embodiment. The intermediate roll bending force changing device 32 constitutes an intermediate roll bending means for applying a bending force to the intermediate roll.

In the above configuration, first, similarly to the first embodiment, the axial thrust load of the work roll 2 is measured by the work roll thrust load detection device 21, and the measured thrust load value and the thrust load limit value are measured. Setting device 22
Then, the work roll intersection angle calculation device 23 performs a comparison calculation with a value set in advance. The work roll crossing angle changing device 24 receives the signal from the work roll crossing angle calculating device 23 and changes the crossing angle of the work roll 2. This corrects the excessive thrust force.

On the other hand, the bending force calculating device 55 receives the signal (θI) from the intermediate roll crossing angle detecting device 34 and the signal (Δθ) from the work roll crossing angle calculating device 23 and receives the bending force change amount of the intermediate roll 3. ΔFI and the bending force change amount ΔFW of the work roll 2 are obtained. This is performed as follows. Change amounts of the plate crown at two points in the width direction of the plate material are represented by ΔCh1 and ΔCh2, respectively.
Then, the relationship between the change in the crossing angle of the work roll 2, Δθ, the bending force change amount ΔFI of the intermediate roll 3, and the bending force change amount ΔFW of the work roll 2 is generally the same as in Equations (9) and (10). Is expressed as follows. ΔCh1 = (Ch1 / θ) Δθ + (Ch1 / FI) ΔFI + (Ch1 / FW) ΔFW (25) ΔCh2 = (Ch2 / θ) Δθ + (Ch2 / FI) ΔFI + (Ch2 / FW) ΔFW (26) where , Each coefficient in parentheses may be obtained in advance by calculation or experiment. However, since these are all functions of the intersection angle θI of the intermediate roll 3, in this embodiment, each coefficient in parentheses is used as a function of θI. The coefficients to be represented may be calculated in advance, and the coefficients in parentheses may be obtained by substituting the intersection angle θI from the intermediate roll intersection angle detection device 34. If ΔCh1 = ΔCh2 = 0 in these equations (25) and (26), the following equation can be obtained similarly to equations (11) and (12). − (Ch1 / θ) Δθ = (Ch1 / FI) ΔFI + (Ch1 / FW) ΔFW (27) − (Ch2 / θ) Δθ = (Ch2 / FI) ΔFI + (Ch2 / FW) ΔFW (28) , (27) and (28) give ΔFI,
Since this is a binary simultaneous equation with ΔFW as an unknown, it can be easily solved, and ΔFI and ΔFW can be easily obtained. These are equivalent bending force change amount ΔFI of the intermediate roll 3 and bending force change amount ΔFW of the work roll 2 for canceling the sheet crown change due to the change amount Δθ of the crossing angle of the work roll 2.
Is represented.

The intermediate roll bending force changing device 32 receives the signal (bending force change amount ΔFI of the intermediate roll 3) from the bending force calculating device 55, and changes the bending force of the intermediate roll 3. The work roll bending force changing device 26 changes the bending force of the work roll 2 in response to a signal (bending force change amount ΔFW of the work roll 2) from the bending force calculation device 55. As a result, it is possible to eliminate the sheet crown change due to the change amount Δθ of the crossing angle of the work roll 2 and maintain the sheet material quality in a good condition.

According to this embodiment, the same effects as those of the fifth embodiment can be obtained. In addition, when obtaining the coefficients in parentheses in Expressions (25) and (26), by using the intersection angle θI from the intermediate roll intersection angle detection device 34, control can be performed with simpler calculations.

FIG. 15 and FIG. 1 show a seventh embodiment of the present invention.
6 will be described. FIG. 15 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to the present embodiment, and FIG. It is a conceptual perspective view showing. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description will be repeated below including those parts.

In FIGS. 15 and 16, the rolling mill according to the present embodiment comprises a pair of upper and lower work rolls 2, 2, and
The rolling stand 5 is provided with upper and lower intermediate rolls 3 and 3 respectively supporting these work rolls and upper and lower reinforcing rolls 4 and 4 respectively supporting these intermediate rolls 3 and 3,
The reinforcing rolls 4 and 4 are configured such that their axes do not incline in the horizontal plane, and the work rolls 2 and 2 are inclined such that their axes intersect each other in the horizontal plane and intersect with the axes of the intermediate rolls 3 and 3, respectively. A lubricant supply device 6 for supplying a lubricant for lubricating between the work rolls 2, 2 and the intermediate rolls 3, 3 is provided. Also,
This rolling mill includes a work roll thrust load detecting device 21 for detecting an axial thrust force of the work roll 2 and a plate crown setting device 28 for setting an allowable plate crown Cht.
And a predetermined limit value F set and stored in advance.
sl and the measured value F of the work roll thrust load detector 21
The value of sm is compared to calculate the change amount Δ of the intersection angle of the work roll 2.
a work roll crossing angle limiting device 27 that obtains θ, a work roll crossing angle changing device 24 that receives a signal from the work roll crossing angle limiting device 27, and changes the crossing angle θ of the work roll 2;
A work roll bending force calculating device 29 which receives a signal from the work roll crossing angle limiting device 27 and a signal from the plate crown setting device 28 and obtains a change amount ΔFW of the bending force of the work roll 2 according to these two; Work roll 2 receiving a signal from force calculation device 29
And a work roll bending force changing device 26 for changing the bending force of the work roll.

In the above description, the plate crown setting device 28 constitutes a crown setting means for externally setting and inputting an allowable crown, and the lubricant supply device 6 lubricates between the work roll and the intermediate roll. The work roll bending changing device 26 constitutes a work roll bending changing device for applying a bending force to the work roll, and the work roll crossing angle changing device 2 constitutes a work roll bending change device 26.
A work roll inclining means 4 inclines a pair of work rolls in a substantially horizontal plane such that their axes intersect each other and each intersects a pair of intermediate rolls. Also, the work roll thrust load detecting device 21
A work roll thrust load detecting means for detecting an axial thrust force of the work roll is constituted. Further, the crossing angle limiter 27 constitutes a crossing angle change amount calculating means for calculating the crossing angle change amount of the work roll according to the value detected by the work roll thrust load detecting means and a predetermined limit value. An inclination control means for controlling the work roll inclination means so that the detection value of the thrust load detection means is equal to or less than a predetermined limit value is also configured. The work roll bending force calculation device 2
9 constitutes a second bending force change amount calculating means for calculating a second bending force change amount of the work roll according to the intersection angle change amount, and according to the control of the work roll tilting means by the tilt control means, Bending control means for controlling the work roll bending means is also configured.

In the above configuration, the work roll thrust load detecting device 21 detects the axial thrust load F of the work roll 2 in the axial direction.
The sm is measured, and the intersection angle of the work roll 2 is changed by the intersection angle limiting device 27 so as to be equal to or less than the limit value Fsl set and input from outside and stored in the intersection angle limiting device 27 in advance.

The calculation processing in the intersection angle limiting device 27 is as follows. The thrust force ΔFs to be corrected can be obtained by subtracting the measured thrust load value Fsm from the thrust load limit value Fsl. If the measured thrust force Fsm is smaller than the limit value Fsl, the following processing is unnecessary and no particular processing is performed. As already described using the equations (1) to (5) of the first embodiment, θ1 ≧ 0.1
If the control is always performed in a region near [degree] (that is, a region in which the change in the thrust coefficient μp between the rolls due to the change Δθ in the work roll crossing angle) is small, the work roll 2
The relationship between the change Δθ in the intersection angle and the change ΔFs in the thrust force can be approximately expressed as follows. ΔFs = −Pr · Cp · Δθ (30) From equation (30), the change Δθ of the work roll intersection angle to be corrected with respect to the thrust force ΔF to be corrected is obtained as follows. Δθ = −ΔF / (Pr · Cp) (31) In the work roll crossing angle changing device 24, the crossing angle limiting device 2
7, the intersection angle θ of the work roll 2 is changed in response to the signal (change amount Δθ of the work roll intersection angle) from the control unit 7. This corrects the excessive thrust force.

On the other hand, the work roll bending force calculating device 29 transmits a signal from the intersection angle limiting device 27 (the change Δθ in the work roll intersection angle) and a signal from the plate crown setting device 28 to the signal (the allowable plate). In response to the crown Cht), the bending force change amount ΔFW of the work roll 2 is obtained. This is performed as follows. The sheet crown Ch of the sheet material is a function of a control amount such as the work roll crossing angle θ and the bending force FW of the work roll 2, and is generally expressed by the following equation.

Ch = fCh (θ, FW) (32) where θ is the crossing angle of the work roll, and FW is the bending force of the work roll 2. The function fCh may be obtained in advance by calculation or experiment. Therefore, assuming that the intersection angle after the angle change by the intersection angle limiting device 27 is θn,
From Equation (32), the plate crown Chn after the angle change is obtained as follows. Chn = fCh (θn, FW) (33) Here, θn is calculated by integrating the signal from the intersection angle limiter 27 (the change Δθ in the work roll intersection angle). Further, FW is calculated by integrating ΔFW output from the work roll bending force calculating device 29 itself to the work roll bending force changing device 26.
Thereafter, the sheet crown Chn after the angle change and the sheet crown set value Cht set and input by the sheet crown setting device 28 are set.
From this, the deviation ΔCh of the sheet crown can be obtained. Here, the relationship between the change amount ΔCh of the sheet crown of the sheet material and the bending force change amount ΔFW of the work roll 2 is as follows.
Generally, it is expressed by the following equation. ΔCh = (Ch / FW) · ΔFW (34) Here, the coefficient (Ch / FW) may be obtained in advance by calculation or experiment. The following equation is obtained from the equation (34). .DELTA.FW = .DELTA.Ch / (Ch / FW) (35) (35) The equation (35) expresses the change of the sheet crown due to the change .DELTA..theta.
This represents an equivalent bending force change amount ΔFW of the work roll 2 for limiting to ht.

The work roll bending force changing device 26 changes the bending force of the work roll 2 in response to a signal (the above-mentioned work roll bending force change amount ΔFW) from the work roll bending force calculating device 29. Thus, similarly to the first embodiment, the sheet crown change due to the change Δθ in the intersection angle of the work roll 2 can be eliminated, and the sheet material quality can be kept good.

As described above, according to this embodiment, similarly to the first embodiment, only the thrust force Fp between the plate member and the work roll 2 can be increased or decreased. 2. The thrust force Fr generated between the intermediate roll 3 and the intermediate roll 3 is made substantially equal, and these two thrust forces Fp and Fr can be canceled out.
Therefore, the thrust force Fs generated on the work roll 2 can be sufficiently reduced. Also, like the conventional structure,
It is not necessary to perform very high-precision control in a region where the relative crossing angle between the work roll and the intermediate roll is small. Therefore, it can be easily realized even with an actual rolling mill.

[0088]

According to the present invention, it is possible to increase or decrease only the thrust force generated between the plate and the work roll by adjusting the crossing angle of the work roll. The thrust force generated between the intermediate rolls is made substantially equal, and these two thrust forces can be canceled. Therefore, the thrust force generated in the work roll can be sufficiently reduced. As a result, the thickness of the roll cloth is restricted due to an increase in the thrust force, and the thickness distribution becomes non-uniform. The plate material can be rolled stably.

[Brief description of the drawings]

FIG. 1 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to a first embodiment of the present invention.

FIG. 2 is a conceptual perspective view illustrating a main structure of a work roll cloth type six-high rolling mill according to the first embodiment of the present invention.

FIG. 3 is a diagram showing an example of characteristics of a thrust force generated between a work roll and a reinforcing roll in the six-high rolling mill shown in FIGS. 1 and 2.

FIG. 4 is a diagram showing an example of a characteristic of a thrust force generated between a work roll and a sheet material in the six-high rolling mill shown in FIGS. 1 and 2;

FIG. 5 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to a second embodiment of the present invention.

FIG. 6 is a conceptual perspective view illustrating a main structure of a work roll cloth type six-high rolling mill according to a second embodiment of the present invention.

FIG. 7 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to a third embodiment of the present invention.

FIG. 8 is a conceptual perspective view illustrating a main structure of a work roll cloth type six-high rolling mill according to a third embodiment of the present invention.

FIG. 9 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to a fourth embodiment of the present invention.

FIG. 10 is a conceptual perspective view showing a main structure of a work roll cloth type six-high rolling mill according to a fourth embodiment of the present invention.

FIG. 11 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to a fifth embodiment of the present invention.

FIG. 12 is a conceptual perspective view illustrating a main structure of a work roll cloth type six-high rolling mill according to a fifth embodiment of the present invention.

FIG. 13 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to a sixth embodiment of the present invention.

FIG. 14 is a conceptual perspective view illustrating a main structure of a work roll cloth type six-high rolling mill according to a sixth embodiment of the present invention.

FIG. 15 is a front view showing the overall schematic structure of a work roll cloth type six-high rolling mill according to a seventh embodiment of the present invention.

FIG. 16 is a conceptual perspective view illustrating a main structure of a work roll cloth type six-high rolling mill according to a seventh embodiment of the present invention.

FIG. 17 is a diagram showing an example of characteristics of a thrust force generated between a work roll and a reinforcing roll in a work roll cloth type four-high rolling mill.

FIG. 18 is a view showing an example of characteristics of a thrust force generated between a work roll and a plate material in a work roll cloth type four-high rolling mill.

[Explanation of symbols]

2 Work Roll 3 Intermediate Roll 4 Reinforcement Roll 6 Lubricant Supply Device (Lubricant Supply Means) 21 Work Roll Thrust Load Detection Device (Work Roll Thrust Load Detection Means) 22 Thrust Load Limit Value Setting Device (Thrust Load Setting Means) 23 Work Roll crossing angle calculating device (crossing angle change amount calculating means, inclination control means) 24 Work roll crossing angle changing device (work roll tilting means) 25 Work roll bending force calculating device (first bending force change amount calculating means, bending control) Means) 26 work roll bending force changing device (work roll bending means) 27 intersection angle limiting device (crossing angle change amount calculating means, inclination control means) 28 sheet crown setting device (crown setting means) 29 work roll bending force calculating device ( Second bending force change amount calculating means, bendy Control device) 32 Intermediate roll bending force changing device (intermediate roll bending device) 33 Intermediate roll axial direction changing device (intermediate roll shifting device) 34 Intermediate roll crossing angle detecting device (intermediate roll crossing angle detecting device) 51 Bending force Calculation device (first bending force change amount calculation means, bending control means) 52 Intermediate roll axial direction position / work roll bending force calculation device (bending control means, shift control means) 53 Intermediate roll axial direction position / bending force calculation device (Bending control means, shift control means) 54 Work roll bending force calculation device (bending control means) 55 Bending force calculation device (bending control means)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenichi Yasuda 7-2-1, Omika-cho, Hitachi City, Ibaraki Prefecture Inside Power & Electricity Development Division, Hitachi, Ltd. (72) Inventor Takehiko Saito Omika-cho, Hitachi City, Ibaraki Prefecture 7-2-1, Hitachi, Ltd. Power and Electricity Development Division (72) Inventor Yukio Hirama 7-2-1, Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi, Ltd. Electricity and Electricity Development Division (72) Inventor Hiroshi Sato 7-2-1, Omika-cho, Hitachi City, Ibaraki Prefecture F-term in the Electric Power & Electric Equipment Development Division, Hitachi, Ltd.

Claims (18)

[Claims] 1. A pair of upper and lower work rolls, a pair of upper and lower intermediate rolls respectively supporting these work rolls, a pair of upper and lower reinforcement rolls respectively supporting these intermediate rolls, Lubricant supply means for supplying a lubricant for lubricating between the intermediate roll, work roll bending means for applying a bending force to the work roll,
A work roll inclining means for inclining the pair of work rolls in a substantially horizontal plane so that their axes intersect with each other and each of the pair of intermediate rolls, Work roll thrust load detecting means for detecting a directional thrust force; inclination control means for controlling the work roll inclining means so that a detection value of the work roll thrust load detecting means is equal to or less than a predetermined limit value; A bending control means for controlling the work roll bending means in accordance with the control of the work roll inclination means by the means. 2. A rolling mill according to claim 1, wherein said inclination control means changes an intersection angle of said work roll in accordance with a value detected by said work roll thrust load detecting means and said predetermined limit value. The work roll inclining means changes the crossing angle of the work roll according to the crossing angle change amount, and the bending control means calculates the crossing angle change amount according to the crossing angle change amount. A first bending force change amount calculating means for calculating a first bending force change amount of the work roll, wherein the work roll bending means is configured to bend the work roll in accordance with the first bending force change amount. A rolling mill characterized by changing the force. 3. The rolling mill according to claim 2, further comprising a thrust load setting means for externally setting and inputting an allowable work roll thrust load as said predetermined limit value. 4. The rolling mill according to claim 1, further comprising a crown setting means for externally setting and inputting an allowable crown, and wherein said inclination control means detects said work roll thrust load detecting means. A cross-angle change amount calculating unit that calculates a cross-angle change amount of the work roll in accordance with a value and the predetermined limit value. And the bending control means calculates a second bending force change amount of the work roll according to the set value of the crown setting means and the cross angle change amount. A change amount calculating means, wherein the work roll bending means changes the bending force of the work roll in accordance with the second bending force change amount. Rolling mill. 5. A rolling mill according to claim 1, further comprising an intermediate roll bending means for applying a bending force to said intermediate roll, and wherein said bending control means is provided with said work roll tilting means by said tilt control means. The work roll bending means and the intermediate roll bending means are controlled according to the control of the rolling mill. 6. A rolling mill according to claim 1, wherein said intermediate roll shift means shifts said intermediate roll in the axial direction, and said intermediate roll shift means is controlled by said tilt control means to control said work roll tilt means. A rolling mill further comprising shift control means for controlling. 7. The rolling mill according to claim 1, wherein: an intermediate roll bending means for applying a bending force to the intermediate roll; an intermediate roll shift means for shifting the intermediate roll in an axial direction; Shift control means for controlling the intermediate roll shift means in accordance with control to the work roll inclining means, and wherein the bending control means controls the work roll inclining means by the inclination control means; A rolling mill for controlling a work roll bending means and the intermediate roll bending means. 8. The rolling mill according to claim 1, wherein said pair of intermediate rolls intersects the axes of said pair of reinforcing rolls, respectively, and the axes of said intermediate rolls intersect each other. And an intermediate roll crossing angle detecting unit that is disposed so as to be inclined in a substantially horizontal plane, and that detects the crossing angle of the pair of intermediate rolls, respectively, and the bending control unit is configured by the tilt control unit. A rolling mill, wherein the work roll bending means is controlled in accordance with the control of the work roll inclination means and the detection result of the intermediate roll crossing angle detection means. 9. The rolling mill according to claim 1, wherein said pair of intermediate rolls intersects the axes of said pair of reinforcing rolls, respectively, and such that the axes of said intermediate rolls intersect each other. Intermediate roll intersecting angle detecting means for detecting the intersecting angle of each of the intermediate rolls, and intermediate roll bending means for applying a bending force to the intermediate rolls, which are arranged inclined in a substantially horizontal plane. And, the bending control means, the control to the work roll inclination means by the inclination control means, according to the detection result of the intermediate roll intersection angle detection means, the work roll bending means and the intermediate roll bending means, A rolling mill. 10. A pair of upper and lower work rolls, a pair of upper and lower intermediate rolls respectively supporting these work rolls,
Using a rolling mill having a pair of upper and lower reinforcing rolls supporting each of the intermediate rolls, supplying a lubricant for lubricating between the work rolls and the intermediate rolls, and applying a bending force to the work rolls In a rolling method for rolling a sheet material, the pair of work rolls are inclined in a substantially horizontal plane so that their axes intersect each other and intersect with the pair of intermediate rolls, respectively. A first procedure for detecting a directional thrust force, a second procedure for inclining the work roll so that the detected value is equal to or less than a predetermined limit value, and applying a bending force to the work roll in accordance with the inclination. And a third procedure for performing the rolling. 11. The rolling method according to claim 10, wherein the second step is performed in accordance with the axial thrust force of the work roll detected in the first step and the predetermined limit value. Calculating the crossing angle change amount of the work roll, and changing the crossing angle of the work roll according to the crossing angle change amount. The third step is to change the crossing angle of the work roll according to the crossing angle change amount. A method of calculating a first bending force change amount and changing the bending force of the work roll according to the first bending force change amount. 12. A rolling method according to claim 11, wherein an allowable work roll thrust load is externally set and input as said predetermined limit value. 13. The rolling method according to claim 10, further comprising a fourth step of externally setting and inputting an allowable crown, and wherein said second step is detected in said first step. In accordance with the axial thrust force of the work roll and the predetermined limit value, a cross angle change amount of the work roll is calculated, and the cross angle of the work roll is changed according to the cross angle change amount. In the third procedure, the second bending force change amount of the work roll is calculated according to the set value set and input in the fourth procedure and the intersection angle change amount, and the second bending is performed. A method of changing a bending force of the work roll according to a force change amount. 14. The rolling method according to claim 10, wherein the third step is a step of applying a bending force to the work roll and the intermediate roll in accordance with the inclination in the second step. A rolling method, characterized in that: 15. The rolling method according to claim 10, further comprising a fifth step of shifting the intermediate roll in the axial direction according to the inclination in the second step. 16. The rolling method according to claim 10, wherein the third step is a step of applying a bending force to the work roll and the intermediate roll in accordance with the inclination in the second step. And a fifth step of shifting the intermediate roll in the axial direction according to the inclination in the second step. 17. The rolling method according to claim 10, wherein said pair of intermediate rolls are arranged such that their axes intersect with the axes of said pair of reinforcing rolls, respectively, and that the axes of said intermediate rolls intersect each other. Rolling is performed by arranging in an inclined manner in a substantially horizontal plane, and further includes a sixth procedure of detecting the intersection angle of the pair of intermediate rolls,
And the third step is a step of applying a bending force to the work roll in accordance with the inclination in the second step and the detection result in the sixth step. . 18. A rolling method according to claim 10, wherein said pair of intermediate rolls are arranged such that their axes intersect with the axes of said pair of reinforcing rolls, respectively, and the axes of said intermediate rolls intersect each other. Rolling by arranging and tilting in a substantially horizontal plane, and further comprising a sixth procedure of detecting the intersection angle of the pair of intermediate rolls,
And, the third procedure is a procedure for applying a bending force to the work roll and the intermediate roll in accordance with the inclination in the second procedure and the detection result in the sixth procedure. Characteristic rolling method.