WO2012128019A1

WO2012128019A1 - Rolling mill and rolling method for metal sheet material

Info

Publication number: WO2012128019A1
Application number: PCT/JP2012/055515
Authority: WO
Inventors: 泰輔岩城; 和宏西山; 邦彦若月; 比護　剛志; 小川　茂
Original assignee: 新日本製鐵株式会社
Priority date: 2011-03-24
Filing date: 2012-03-05
Publication date: 2012-09-27
Also published as: JPWO2012128019A1; KR101392078B1; JP5059250B1; CN103237609A; EP2626149A1; CN103237609B; EP2626149A4; TW201304886A; KR20130069875A; TWI496630B; EP2626149B1

Abstract

The present invention provides a rolling mill for metal sheet material comprising: a housing that accommodates roll chocks, has a pair of first projecting blocks projecting inward toward each other and bearing the force in the direction of rolling that operates on a lower work roll, and forms a housing window that bears the force in the direction of rolling that operates on an upper work roll; a first hydraulic cylinder provided on the pair of first projecting blocks and having a first piston rod that imposes a bending increasing force on the upper work roll; a second hydraulic cylinder provided on the pair of first projecting blocks and having a second piston rod that imposes a bending increasing force on the lower work roll; a third hydraulic cylinder provided on an upper reinforcing roll chock and having a third piston rod that imposes a bending decreasing force on the upper work roll, or makes the upper work roll contact an upper reinforcing roll and generates a roll balance force; and a fourth hydraulic cylinder having a fourth piston rod that imposes a bending decreasing force on the lower work roll.

Description

Metal plate rolling machine and rolling method

The present invention relates to a rolling machine and a rolling method for a metal plate material. The present invention is particularly suitable for a thick plate rolling machine, a thin plate hot rolling rough rolling mill or a finishing rolling mill, and can make a large maximum opening between the upper and lower work rolls and easily provide a strong roll bending force. The present invention relates to a rolling mill that can be imparted, and as a result, can impart a highly responsive and powerful sheet crown / shape control function, and a rolling method using the rolling mill.
This application claims priority on March 24, 2011 based on Japanese Patent Application No. 2011-066153 filed in Japan, the contents of which are incorporated herein by reference.

Conventionally, as in the

rolling mills

1A and 1B shown in FIGS. 12 and 13, a rolling mill of a type in which a reinforcing roll chock holds and holds a work roll chock is known in order to take a large roll opening. However, since the increase bending apparatus is incorporated into the arm for holding the work roll chock extending from the reinforcing roll chock, it is difficult to incorporate a large capacity hydraulic cylinder.

For example, the rolling mill type disclosed in Patent Document 1 is a four-high rolling mill, and the rolling mill type has a structure shown in FIG. That is, the upper work roll chock 3-1 is held by the arm portion connected to the upper reinforcement roll chock 4-1. By incorporating upper increase bending devices 6-1 and 6-2 acting on the upper work roll 1-1 into this arm portion, a large roll opening degree can be obtained.

However, this type of rolling mill has the following problems.
(1) The upper increment bending devices 6-1 and 6-2 must be incorporated in the arm portion of the upper reinforcing roll chock 4-1 that holds the upper work roll chock 3-1. Therefore, it is difficult to incorporate a large capacity hydraulic cylinder.

(2) When a strong increase bending force is applied to the upper work roll 1-1, the arm connected to the upper reinforcing roll chock 4-1 receives a moment in the direction of opening outward. In this case, due to the possibility that the arm portion is pressed against the housing window and the thickness accuracy deteriorates due to an increase in mill hysteresis, and the left-right asymmetry of the chock-window frictional force, The possibility of causing problems such as an increase in rolling operation instability due to the occurrence of camber increases. Therefore, a strong work roll bender may be substantially unusable.

(3) The upper work roll chock 3-1 contacts the inner side surface of the arm portion of the upper reinforcing roll chock 4-1, and further, the side surface of this arm portion contacts the inner side surface of the housing window. Therefore, the risk of occurrence of meandering / cambering of the metal plate during rolling due to an increase in the shakiness in the rolling direction increases.

(4) Space restrictions are severe and wiring around the reinforcing roll chock is particularly complicated when replacing the reinforcing roll. Therefore, it is difficult to provide a mill stabilizer and a load cell for measuring the rolling direction force.

On the other hand, in order to obtain a large roll opening degree, there exists a rolling mill in which the increment bending apparatuses 6-1 and 6-2 are incorporated in the lower work roll chock 3-2 as in the rolling mill 1C shown in FIG.
For example, Patent Document 2 discloses a rolling mill in which an increase bending apparatus for a work roll is incorporated in a work roll chock.
Similarly, Patent Document 3 discloses a roll-cross type rolling mill. Also in this rolling mill, the increment bending apparatus is incorporated in the work roll chock.

This type of rolling mill has the following problems.
(5) When changing the work roll, it is necessary to attach and detach the hydraulic piping. If it is attempted to attach and detach easily, flexible piping must be employed, and it becomes difficult to employ a servo valve for high response hydraulic control. Therefore, it is difficult to configure a bending device with high responsiveness.

Also, in order to obtain a highly responsive bending apparatus, a rolling mill in which an increment bending apparatus is provided in a project block is well known.

For example, Patent Document 4 discloses a rolling mill having a work roll shift function. In this rolling mill, as shown in FIG. 15, the increment bending apparatuses 6-1 to 6-4 are incorporated in project blocks 5-1 and 5-2 integrated with the housing 9.

In the rolling mill 1D shown in FIG. 15, the lower increase bending apparatuses 6-3 and 6-4 acting on the lower work roll 1-2 are incorporated in a project block protruding inward from the housing 9.

However, this type of rolling mill has the following problems.
(6) Since the contact surface between the project block and the work roll chock supports the rolling direction force acting on the work roll, the contact surface becomes smaller as the roll opening is increased. Accordingly, it is impossible to properly support the work roll chock, and a large roll opening degree cannot be obtained.

(7) The capacity of the hydraulic cylinder of the increment bending apparatus is limited by the height of the project block. Therefore, in a rolling mill that cannot sufficiently secure the height of the project block, the stroke length of the hydraulic cylinder cannot be sufficiently ensured, and a large roll opening cannot be obtained.

The increment bending apparatus means a hydraulic apparatus that applies a force in the direction of increasing the roll opening degree to the work roll chock, and is a generic name for an apparatus including a hydraulic cylinder that is an actuator and a piston rod.

However, in the present invention, in order to simplify the description, the increment bending apparatus refers to a hydraulic cylinder and its piston rod as its actuator unless otherwise specified. The force applied to the work roll by the increment bending apparatus is referred to as an increment bending force.

On the other hand, a hydraulic device that applies a force in the direction of decreasing the roll opening to the work roll chock is referred to as a decrease bending device. A force applied to the work roll by the decrease bending apparatus is referred to as a decrease bending force. The decrease bending device is a general term for devices including a hydraulic cylinder as an actuator and a piston rod. However, in the present invention, for the sake of simplicity, the decrease bending device refers to a hydraulic cylinder and a piston rod as actuators unless otherwise specified.

In general, a rolling machine for producing thick steel plates is not provided with a decrease bending apparatus as shown in FIGS. 12 to 16 (see Patent Documents 1 to 4).
This is because (A) in the case of thick plate rolling, a relatively large diameter work roll is used compared to thin plate rolling, so that even if the same bending force is applied, the change in roll crown shape is small. (B) Compared with the sheet rolling mill, even if a small decrease bending device is installed in a narrow area around a relatively large diameter work roll chock, the control range is narrow and the mechanical structure is only complicated. This is due to disadvantages in cost performance.

Japanese Unexamined Patent Publication No. 6-87011 Japanese Unexamined Patent Publication No. Sho 62-220205 Japanese Laid-Open Patent Publication No. 6-198307 Japanese Unexamined Patent Publication No. 4-52014

As described above, in the rolling mill capable of taking a large roll opening, there is no rolling mill type that can incorporate a powerful roll bending apparatus with high responsiveness.
The problem to be solved by the present invention is to provide a rolling mill capable of increasing the maximum opening between the upper and lower work rolls and imparting a strong roll bending force, and a rolling method using the rolling mill. That is.
That is, an object of the present invention is to provide a rolling mill that can accommodate a wide range of steel plates, and on the premise that the same bending bending apparatus as that of a thin sheet rolling mill is provided, a roll between upper and lower work rolls. The present invention is to provide a rolling mill that can take a large opening and that can easily impart a strong roll bending force and overcomes the above-mentioned drawbacks of the conventional rolling mill and a rolling method using this rolling mill. .

The gist of the present invention is as follows.
(1) A first aspect of the present invention includes an upper work roll and a lower work roll for rolling a metal plate material; an upper reinforcement roll and a lower reinforcement roll that respectively support the upper work roll and the lower work roll; An upper work roll chock and a lower work roll chock that respectively support the work roll and the lower work roll; an upper reinforcement roll chock and a lower reinforcement roll chock that respectively support the upper reinforcement roll and the lower reinforcement roll; the upper work roll chock and the lower work A pair of first project blocks that house a roll chock, the upper reinforcing roll chock, and the lower reinforcing roll chock and that bear in the rolling direction force acting on the lower work roll projecting inward from each other are provided on the upper work roll. A housing window is formed that bears the acting rolling direction force. A first hydraulic cylinder provided in the pair of first project blocks and having a first piston rod for applying an increase bending force to the upper work roll via the upper work roll chock; and the pair of first projects A second hydraulic cylinder provided in a project block and having a second piston rod for applying an increment bending force to the lower work roll via the lower work roll chock; and provided in the upper reinforcing roll chock, A third hydraulic cylinder having a third piston rod for applying a decrease bending force or bringing the upper work roll into contact with the upper reinforcing roll to generate a roll balance force; and a decrease bending force for the lower work roll 4th piston rod to give A fourth hydraulic cylinder and; a rolling mill of a metal plate with a.
(2) In the metal sheet material rolling mill according to (1), the first hydraulic cylinder and the second hydraulic cylinder are provided at different positions on the plan view in the pair of first project blocks. May be.
(3) In the rolling mill for a metal sheet according to (1) or (2), the lower reinforcing roll chock may be provided with the fourth hydraulic cylinder.
(4) In the metal sheet rolling mill according to (1) or (2), the housing includes a pair of second project blocks that project inward from the housing below the pair of first project blocks. Further, the fourth hydraulic cylinder may be provided in the pair of second project blocks.
(5) In the metal plate rolling mill according to any one of (1) to (4), a first engagement portion is formed at a tip portion of the third piston rod, and the upper work roll chock A second engagement portion may be formed in which the first engagement portion is engaged by movement of the upper work roll in the roll axial direction.
(6) A second aspect of the present invention is a method of rolling a metal sheet using the rolling mill described in any one of (1) to (5) above, wherein the first hydraulic cylinder When rolling at a roll opening degree exceeding the stroke, the rolling method of the metal plate material is such that a roll balance force is generated by pulling the third piston rod.
(7) A third aspect of the present invention is a method of rolling a metal sheet using the rolling mill described in any one of (1) to (5) above, wherein the first hydraulic cylinder When rolling at a roll opening that does not exceed the stroke, before the rolling is started, both the increase bending force and the decrease bending force are applied to the upper work roll and the lower work roll, thereby producing a roll as a resultant force. A first step of applying a roll bending force corresponding to a balance force to the upper work roll and the lower work roll, and then changing the decrease bending force to a decrease bending force corresponding to a decrease bending force during rolling. However, the second step of increasing the increase bending force so that the resultant force maintains the roll balance force; At the start of rolling, by changing the increase bending force while maintaining the decrease bending force, a roll bending force corresponding to the roll bending force during rolling acts on the upper work roll and the lower work roll as a resultant force. A third step of rolling, a fourth step of performing rolling while maintaining the roll bending force during rolling, and a resultant force by changing the increase bending force while maintaining the decrease bending force at the end of rolling. As a fifth step of applying a roll bending force corresponding to the roll balance force to the upper work roll and the lower work roll and ending the rolling of the metal sheet in this state, and then maintaining the roll balance force The decrease bending force and the increment bending A sixth step of reducing the force, a rolling method for a metal sheet to perform.
(8) In the method for rolling a metal plate material according to (7), the hydraulic pressure in the third hydraulic cylinder, the hydraulic pressure in the hydraulic piping connected to the third hydraulic cylinder, the hydraulic pressure in the fourth hydraulic cylinder, and At least one of the hydraulic pressures in the hydraulic piping connected to the fourth hydraulic cylinder is continuously measured, and based on the measured value, the roll bending force acting on the upper work roll chock and the lower work roll chock is a predetermined force. The increase bending force may be controlled to be a value.
(9) A fourth aspect of the present invention is a method for rolling a metal plate material using the rolling mill described in any one of (1) to (5) above, wherein the first hydraulic pressure is applied during rolling. When rolling at a roll opening degree exceeding the stroke of the cylinder, the roll balance force of the upper work roll is applied by pulling the third piston rod, and then the stroke of the first hydraulic cylinder is not exceeded. When rolling at a roll opening degree, both the increase bending force and the decrease bending force are applied to the upper work roll and the lower work roll before the start of rolling. A first step in which a roll bending force is applied to the upper work roll and the lower work roll, and then the decrease bending force is applied during rolling. A second step of increasing the increase bending force so that the resultant force maintains the roll balance force while changing to a decrease bending force corresponding to the crease bending force, and at the start of rolling, the decrease bending force is increased. A third step in which a roll bending force corresponding to a roll bending force during rolling is applied to the upper work roll and the lower work roll as a resultant force by changing the increase bending force while holding,
A fourth step of performing rolling while maintaining the roll bending force during rolling, and changing the increase bending force while maintaining the decrease bending force at the end of rolling, thereby changing the roll balance force as a resultant force. A fifth bending step in which a corresponding roll bending force is applied to the upper work roll and the lower work roll, and the rolling of the metal plate material is finished in this state, and then the decrease bending is performed so as to maintain the roll balance force. And a sixth step of reducing the increase bending force and the increase bending force.
(10) In the rolling method of the metal plate material according to (9), the hydraulic pressure in the third hydraulic cylinder, the hydraulic pressure in the hydraulic piping connected to the third hydraulic cylinder, the hydraulic pressure in the fourth hydraulic cylinder, and At least one of the hydraulic pressures in the hydraulic piping connected to the fourth hydraulic cylinder is continuously measured, and based on the measured value, the roll bending force acting on the upper work roll chock and the lower work roll chock is a predetermined force. The increase bending force may be controlled to be a value.

According to the rolling mill and the rolling method described in the above (1) to (10), the maximum opening between the upper and lower work rolls can be increased, and a decrease bending device having low response must be provided. Even if it is not, this can be compensated by a highly responsive increase bending device arranged in the pair of first project blocks, and a highly responsive and powerful plate crown / shape control function can be provided.
Therefore, it is possible to build a good plate crown and shape against disturbances that change during rolling, such as the rolled material entry side thickness and the rolled material temperature, which can greatly improve product quality and yield. .
Also, not only can the upper work roll be provided with an increase bending force and a decrease bending force to realize a powerful plate crown and shape control function, but also the upper work roll decrease bending machine has a double-acting hydraulic cylinder. The roll balance force can be generated by adopting, so that a large opening roll gap can be realized. In other words, a single unit can cope with the bulk rolling with a large plate thickness to the hot rolled thin plate rolling that requires accurate plate crown and shape control.
Further, since the rolling direction force applied to the upper work roll chock is always borne by the housing window, the upper work roll chock can be stably supported.
In addition, the upper and lower increase bending apparatuses can be incorporated into the pair of first project blocks. As a result, a large-capacity and large-stroke powerful bending device can be realized.
Further, by incorporating the increment bending apparatus into the pair of first project blocks, the hydraulic piping can be fixed and the servo valve can be applied. As a result, it is possible to control the incremental bending force with high response.
Even with a decrease bending device with low responsiveness, roll bending force control with high response becomes possible by cooperating with an increase bending device with high responsiveness. This greatly improves product quality and rolling yield.

It is a side view which shows the structure of the rolling mill which concerns on one Embodiment of this invention. It is a figure which shows the connection structure of an upper work roll chock and an upper decrease bending apparatus. It is sectional drawing which shows the 1st aspect of the engagement relation of the 1st engagement part of the 3rd piston rod of a 3rd hydraulic cylinder, and the 2nd engagement part of an upper work roll chock. It is sectional drawing which shows the 2nd aspect of the engagement relation of the 1st engagement part of the 3rd piston rod of a 3rd hydraulic cylinder, and the 2nd engagement part of an upper work roll chock. It is sectional drawing which shows the 3rd aspect of the engagement relation of the 1st engagement part of the 3rd piston rod of a 3rd hydraulic cylinder, and the 2nd engagement part of an upper work roll chock. It is a perspective top view which shows the example of arrangement | positioning of an upper and lower increase bending apparatus. It is a perspective top view which shows the example of arrangement | positioning of an upper and lower increase bending apparatus. It is a side view which shows another example of the structure of the rolling mill which concerns on one Embodiment of this invention. It is a figure which shows an example of the operation flow of the rolling method which concerns on one Embodiment of this invention. It is a figure which shows time-sequential changes, such as roll bending force accompanying the operation flow of FIG. It is a figure which shows time-sequential changes, such as roll bending force, when the responsiveness of a decrease bending apparatus is very low. It is a figure which shows another example of the operation flow of the rolling method which concerns on one Embodiment of this invention. It is a figure which shows time-sequential changes, such as roll bending force accompanying the operation flow of FIG. It is a side view which shows the structure of the rolling mill 1A which concerns on a prior art. It is a side view which shows the structure of the rolling mill 1B which concerns on a prior art. It is a side view which shows the structure of the rolling mill 1C which concerns on a prior art. It is a side view which shows the structure of rolling mill 1D which concerns on a prior art. It is a side view which shows the structure of the rolling mill 1E which concerns on a prior art.

Hereinafter, a rolling mill according to the present invention based on the above-described knowledge and a rolling method using the rolling mill will be described with reference to FIGS.
FIG. 1 is a side view showing an example of the structure of a rolling mill 1 according to an embodiment of the present invention. As shown in the drawing, the rolling mill 1 according to an embodiment of the present invention includes an upper work roll chock 3-1 and a lower work roll chock 3-2, an upper reinforcement roll chock 4-1, and a lower reinforcement roll chock 4-2. And a housing 9 for accommodating these roll chock. The housing 9 is integrally formed with a pair of first project blocks 5-1 and 5-2 (that is, a first project block provided on the entrance side of the metal plate and a first project block provided on the exit side). A housing window 12 is also formed.
The upper work roll chock 3-1 supports the upper work roll 1-1 for rolling the metal plate material, and the lower work roll chock 3-2 supports the lower work roll 1-2 for rolling the metal plate material.
The upper reinforcement roll chock 4-1 supports the upper reinforcement roll 2-1 disposed above the upper work roll 1-1, and the lower reinforcement roll chock 4-2 is disposed below the lower work roll 1-2. To support the lower reinforcing roll.

The pair of first project blocks 5-1 and 5-2 are integrally formed so as to project inward from the housing 9. The pair of first project blocks 5-1 and 5-2 includes an upper increment bending apparatus 6-1 that applies an increase bending force to the upper work roll 1-1 via the upper work roll chock 3-1. 6-2, and lower increment bending apparatuses 6-3 and 6-4 for applying an increment bending force to the lower work roll 1-2 via the lower work roll chock 3-2 are provided.
Specifically, the upper increment bending apparatuses 6-1 and 6-2 are configured by a first hydraulic cylinder as an actuator and a piston rod (first piston rod). The first hydraulic cylinder is built in the pair of first project blocks 5-1 and 5-2, and the first piston rod protrudes from the upper surface of the pair of first project blocks 5-1 and 5-2. It is provided in contact with the work roll chock 3-1.
Further, the lower increase bending apparatuses 6-3 and 6-4 are configured by a second hydraulic cylinder, which is an actuator, and a piston rod (second piston rod). The second hydraulic cylinder is built in the pair of first project blocks 5-1 and 5-2, and the tip of the second piston rod protrudes from the lower surface of the pair of first project blocks 5-1 and 5-2. Provided in contact with the work roll chock 3-2.

Further, the rolling mill 1 according to the present embodiment has a function of applying a decrease bending force to the upper work roll 1-1 via the upper work roll chock 3-1, and the upper work roll 1-1 as the upper reinforcing roll 2. -1 and 7-2 having a function of applying a pulling force (roll balance force) to be brought into contact with -1 are arranged in the upper reinforcing roll chock 4-1.
The upper decrease bending apparatuses 7-1 and 7-2 having the above two functions are constituted by a third hydraulic cylinder as an actuator and a piston rod (third piston rod). The third hydraulic cylinder is disposed in the upper reinforcing roll chock 4-1. The tip of the third piston rod has a shape that engages with the upper work roll chock 3-1.

Further, the rolling mill 1 according to this embodiment includes lower decrease bending apparatuses 7-3 and 7-4 that apply a decrease bending force to the lower work roll 1-2 via the lower work roll chock 3-2.
The lower decrease bending devices 7-3 and 7-4 are configured by a fourth hydraulic cylinder, which is an actuator, and a piston rod (fourth piston rod). The fourth hydraulic cylinder is arranged in the lower reinforcing roll chock 4-2 or is built in a pair of second project blocks 5-3 and 5-4 described later. The fourth piston rod is provided so that the tip thereof is in contact with the lower work roll chock 3-2.

形式 There are many types of hot rolling finishing mills in which an increment bending device is installed in the project block and a decrease bending device is installed in the vertical reinforcement roll chock. However, in this form, the contact force between the upstream side surface of the project block provided on the exit side of the metal plate and the work roll chock must support the rolling direction force during the rolling operation. For this reason, as the roll opening degree is increased, the center position of the rotational moment of the upper work roll deviates upward from the contact surface, and the area of the contact surface supporting the rolling direction force decreases. Therefore, even if the height of the pair of project blocks is increased in the upper work roll chock, the contact surface between the upstream side surface of the project block and the work roll chock decreases as the roll opening increases, and the upper work roll chock The posture becomes unstable and a large roll opening cannot be obtained.

In order to improve this point, the upper reinforcing roll chock 4-1 shown in FIG. 16 is a type of rolling mill 1E having a type that includes an arm for holding the upper work roll chock 3-1 and is often used in a thick plate finishing rolling mill. . In this type of rolling mill, since the upper reinforcing roll chock 4-1 holds the upper working roll chock 3-1, the upper working roll 1-1 is lifted as the upper reinforcing roll 2-1 is pulled up, and a large roll The opening can be taken.

However, the structure of this rolling mill cannot take a sufficient place for installing the increment bending device and the decrease bending device for the upper work roll 1-1. Therefore, as shown in FIG. 16, normally, for the upper work roll 1-1, the small-capacity increase bending apparatuses 6-1 and 6-2 are connected to the upper reinforcement roll chock 4-1 and the upper work roll chock 3-1. The decrease bending device for the upper work roll 1-1 is not provided. Therefore, there is a drawback that the shape control capability is limited.

Furthermore, the rolling direction force acting on the upper work roll 1-1 is received by the contact surface on the downstream side in the rolling direction between the upper reinforcement roll chock 4-1 and the upper work roll chock 3-1. This force is finally received at the contact surface formed by the contact surface between the outer surface of the upper reinforcing roll chock 4-1 in the rolling direction downstream arm and the inner side of the housing window 12. However, the contact surface on the downstream side in the rolling direction has a small space, and it is difficult to provide a load cell that can sufficiently support the upper work roll chock 3-1. In addition to the backlash remaining on the contact surface between the upper reinforcing roll chock 4-1 and the housing window 12, a stabilizer and a load cell are required for each reinforcing roll chock, and the workability of the wiring operation for operating them is significantly reduced. I am letting.

Therefore, in the rolling mill 1 according to the present embodiment, as shown in FIG. 1, the pair of first project blocks 5-1 and 5-2 projecting inward from the housing 9 is shifted downward with respect to the pass line. Place it at the specified position. That is, unlike the conventional method shown in FIG. 15, a pair of first project blocks 5-1 and 5-2 are arranged at positions that are vertically asymmetric with respect to the pass line. Further, regarding the shape of the upper work roll chock 3-1, the height of the portion sandwiched between the pair of first project blocks 5-1 and 5-2 is not increased, but the pair of first project blocks 5-1. The height of the base portion adjacent to the portion sandwiched between -1, 5-2, in other words, the upper portion corresponding to the width of the housing window 12 (housing window width) is increased.

Thereby, in the rolling mill 1 according to the present embodiment, the upper portion corresponding to the housing window width of the upper work roll chock 3-1 and the housing window positioned above the pair of first project blocks 5-1 and 5-2. 12, the rolling direction force such as offset component force acting on the upper work roll 1-1, that is, the metal plate material 10, the upper reinforcing roll 2-1 and the like is applied to the trunk of the upper work roll 1-1. Bearing the rolling direction force.

With such a structure, even if the roll opening degree is increased by operating the rolling device 11 of the rolling mill 1, the area of the surface where the upper work roll chock 3-1 and the housing window 12 are in contact with each other does not change at all. Accordingly, the posture of the upper work roll chock 3-1 is always stably maintained regardless of the roll opening degree.

Further, in the rolling mill 1 according to the present embodiment, the upper increment bending devices 6-1 and 6-2 for applying the increment bending force to the upper work roll 1-1 and the increase bending to the lower work roll 1-2. Lower increase bending apparatuses 6-3 and 6-4 that apply force are arranged in a pair of first project blocks 5-1 and 5-2 that protrude inside the housing 9.

Therefore, it is not necessary to attach and detach the hydraulic piping of the increment bending device every time the work rolls are recombined, and by using a fixed piping, it is possible to obtain a highly responsive incremental bending device using a precise servo valve. it can.

Also, the upper decrease bending devices 7-1 and 7-2 are constituted by a third hydraulic cylinder and its third piston rod built in the upper reinforcing roll chock 4-1. Then, the tip of the third piston rod of the third hydraulic cylinder can be connected to the upper work roll chock 3-1 by a roll axial movement operation accompanying roll exchange or the like, and a roll balance force is applied.

As a result, the roll opening can be increased regardless of the stroke of the increment bending apparatus, and a strong decrease bending force can be applied in cases where plate crown control with a plate thickness of about 100 mm or less is required. . Thereby, it is possible to deal with one rolling mill 1 from rolling of a rolled material having a thickness of more than 800 mm to rolling with precise plate crown control in rolling of a plate having a thickness of 100 mm or less.

Hereinafter, an example of the structure of the connecting portion will be described in detail. This example is merely an embodiment and does not limit the specific structure of the present invention.
FIG. 2 is a sketch of the upper work roll 1-1 and the upper work roll chock 3-1, in which the front side is the drive side and the back side is the work side. On the left and right sides of the upper surface of the roll chock 3-1 of the upper work roll 1-1, the cross-section reverse T where the tip of the third piston rod of the third hydraulic cylinder constituting the upper decrease bending devices 7-1 and 7-2 is fitted. A letter-shaped groove 31 is formed as a first engaging portion. The groove 31 is open to the drive side and is formed to the vicinity of the center of the chock.
When inserting the roll set into the rolling mill 1, when the work roll having the roll chock set on both ends from the operation side is carried into a predetermined position in the housing of the rolling mill 1 using a rail or the like, the upper reinforcing roll chock 4- The piston rod of the hydraulic cylinder, which is a decrease bending device, is pulled into 1 so as not to obstruct the loading.
Next, when the groove 31 of the upper work roll chock 3-1 is positioned immediately before the enlarged portion (second engaging portion) of the third piston rod of the third hydraulic cylinder to be engaged, Lower to position. As shown in FIG. 3C, the enlarged portion of the third piston rod is inserted into the groove 31 from the groove opening on the driving side while maintaining the positional relationship where the inner surface of the groove 31 and the outer surface of the third piston rod do not contact each other. Let it enter. Thereby, engagement with the 1st engaging part and the 2nd engaging part is realized.

FIG. 3A is a view showing a state in which the enlarged portion formed at the tip of the third piston rod of the third hydraulic cylinder of the upper decrease bending devices 7-1 and 7-2 is engaged with the groove 31. FIG. Specifically, FIG. 3A shows that the third piston rod is pulled upward by the pulling operation of the third hydraulic cylinder and abuts on the upper surface of the groove 31 of the upper work roll chock 3-1 to apply the rising force fRB. Indicates the state.

The ascending force fRB acts as a roll balance force. For this reason, the upper work roll 1-1 is not dependent on the stroke of the first piston rod of the upper increment bending apparatuses 6-1 and 6-2 provided in the pair of first project blocks 5-1 and 5-2. Can be raised together with the upper reinforcing roll 2-1. Therefore, a large roll opening can be taken without difficulty.

FIG. 3B is a diagram illustrating a state in which an upper decrease bending force is applied in the case of performing sheet crown / shape control such as finish rolling of thin sheet hot rolling.
That is, by the third hydraulic cylinders of the upper decrease bending devices 7-1 and 7-2, the third piston rod extends downward, and the pressing force fDC is applied to the bottom surface of the groove 31 of the upper work roll chock 3-1. By doing so, it gives the decrease bending power.

FIG. 3C is a diagram showing a non-contact state when the groove 31 and the third piston rod are engaged with each other and when the engagement is released as described above.

In the above example, the groove 31 is formed in the upper work roll chock 3-1, and the enlarged portion that engages with the groove 31 is formed in the upper decrease bending apparatuses 7-1 and 7-2. For example, the groove 31 is formed in the upper decrease bending apparatuses 7-1 and 7-2, and the enlarged portion that engages with the groove 31 is formed in the upper work roll chock 3-1. Also good.

In the rolling mill 1 according to the present embodiment, the rolling direction force applied to the body portion of the lower work roll 1-2 is the lower work roll chock 3-2 and the project block (5-1 or 5) provided on the exit side. It is borne by the contact surface with 5-2). Therefore, in the rolling mill 1 according to this embodiment shown in FIG. 1, the height of the portion sandwiched between the pair of first project blocks 5-1 and 5-2 of the lower work roll chock 3-2 is increased.

Also, since the roll opening is adjusted mainly by moving the upper work roll chock 3-1 up and down, the vertical movement amount of the lower work roll chock 3-2 is small. Therefore, the posture of the lower work roll 1-2 does not become unstable as the roll opening increases.

FIG. 4 is a plan sectional view showing an arrangement example of the upper and lower increase bending apparatuses 6-1 to 6-4. That is, it is a cross-sectional view of the pair of first project blocks 5-1 and 5-2 at the pass line height.
In the rolling mill 1 according to this embodiment, the upper and lower increase bending apparatuses 6-1 to 6-4 are arranged so as to be shifted from each other on the plan sectional view of the pair of first project blocks 5-1, 5-2. It is desirable. For example, as shown in FIG. 4, the upper increment bending apparatuses 6-1 and 6-2 and the lower increment bending apparatuses 6-3 and 6-4 are shifted in the axial direction of the work roll 1-2. It is desirable to deploy in a relationship. In this way, the upper and lower increase bending apparatuses 6-1 to 6-4 do not interfere with each other in each of the pair of first project blocks 5-1 and 5-2.
That is, the first hydraulic cylinder and the second hydraulic cylinder built in each of the first project blocks 5-1 and 5-2 do not interfere with each other. For this reason, the capacity of the first hydraulic cylinder and the second hydraulic cylinder can be increased, and the strokes of the first piston rod and the second piston rod can be increased to increase the increment bending operation amount.

In FIG. 4, the lower increment bending devices 6-3 and 6-4 are each constituted by two second hydraulic cylinders on the inlet side and the outlet side. However, the same action and effect can be obtained also by arranging one second hydraulic cylinder and one lower hydraulic cylinder 1-2 at different positions so as not to interfere with the first hydraulic cylinder.

FIG. 5 is also a plan sectional view showing an arrangement example of the upper and lower increase bending apparatuses 6-1 to 6-4. That is, it is a cross-sectional view of the pair of first project blocks 5-1 and 5-2 at the pass line height. As shown in the figure, the first hydraulic cylinder and the second hydraulic cylinder may be in a positional relationship shifted in the rolling direction. Even in such an arrangement, the first hydraulic cylinder and the second hydraulic cylinder do not interfere with each other. For this reason, it is possible to increase the bending operation amount by increasing the capacities of the first hydraulic cylinder and the second hydraulic cylinder and increasing the strokes of the first piston rod and the second piston rod.
So far, the structure of the rolling mill 1 according to the present embodiment has been described mainly from the viewpoint of obtaining a large roll opening, which is one of the problems to be solved.

Next, it will be described that according to this structure, it is possible to easily achieve the application of a strong roll bending force, which is another problem to be solved.
12 and 13 are rolling

mills

1A and 1B according to the prior art, and any rolling mill can take a large roll opening.
However, these rolling

mills

1A and 1B cannot provide a strong roll bending force. This is a structure in which the upper increment bending devices 6-1 and 6-2 are incorporated in the arm portion projecting downward from the upper reinforcing roll chock 4-1, so that the upper increase bending device 6- has a large capacity and a large stroke. This is because 1,6-2 cannot be deployed. In addition, since these rolling

mills

1A and 1B extend the arm portion from the upper reinforcing roll chock 4-1, even if it is attempted to install the upper decrease bending apparatuses 7-1 and 7-2, the installation space is the axis of the roll. I'm close to my heart. Therefore, since it interferes with the bearing of the upper reinforcing roll 2-1, the upper capacity bending devices 7-1 and 7-2 having a large capacity and a large stroke cannot be provided.

On the other hand, as shown in FIG. 1, in the rolling mill 1 according to the present embodiment, a large capacity is provided from the housing 9 of the rolling mill 1 to the pair of first project blocks 5-1 and 5-2 projecting inward. A large stroke upper increment bending device 6-1 or 6-2 can be provided.
Further, in the rolling mill 1 according to this embodiment, the upper reinforcing roll chock 4-1 does not include the arm portions as in the

rolling mills

1A and 1B shown in FIGS. For this reason, large-capacity and large-stroke upper decrease bending devices 7-1 and 7-2 can be installed at positions where they do not interfere with the bearings of the upper reinforcing roll 2-1 of the upper reinforcing roll chock 4-1. Thus, a large decrease bending force can be applied to the upper work roll 1-1.

That is, the position of the pair of first project blocks 5-1 and 5-2 and the rolling direction force applied to the body of the upper work roll 1-1 are brought into contact with the upper work roll chock 3-1 and the housing window 12. According to the rolling mill 1 according to the present embodiment having a structure that bears a load, a large roll opening degree can be obtained and a strong roll bending force can be applied.
Moreover, it is not necessary to attach or detach the hydraulic piping of the increment bending apparatus every time the work roll is recombined. For this reason, each of the increment bending apparatuses 6-1 to 6-4 can be connected to each hydraulic control valve via a fixed hydraulic pipe and employs a servo valve for high response hydraulic control. be able to. Therefore, it is possible to provide an incremental bending apparatus with high responsiveness.

FIG. 6 is a side view showing a rolling mill 1 ′ according to a modification of the present embodiment. In the rolling mill 1 ′ shown in FIG. 6, the upper roll system has the same configuration as that in FIG. 1, but the lower roll system has a different configuration. In the rolling mill 1 shown in FIG. 1, lower decrease bending apparatuses 7-3 and 7-4 that apply a decrease bending force to the lower work roll 1-2 are provided in the lower reinforcing roll chock 4-2. On the other hand, in the rolling mill 1 ′ shown in FIG. 6, the lower decrease bending apparatuses 7-3 and 7-4 are arranged below the pair of first project blocks 5-1 and 5-2. Deployed in blocks 5-3 and 5-4.

By the way, when the lower decrease bending devices 7-3 and 7-4 are arranged in the lower reinforcing roll chock 4-2 as in the rolling mill 1 shown in FIG. 1, when the lower reinforcing roll 2-2 is rearranged, the decrease bending is performed. Equipment hydraulic piping must be removed. In other words, there is a high possibility that minute foreign matter will be mixed in the hydraulic piping during attachment / detachment.
For this reason, it is generally difficult to employ a servo valve for high response hydraulic pressure control, and flexible piping may have to be partially employed.
Therefore, the responsiveness of the roll bending apparatus is inevitably lowered as compared with the case where fixed piping and servo valves are employed.

On the other hand, according to the rolling mill 1 ′ shown in FIG. 6, the above-mentioned problem that occurs when the lower reinforcing roll 2-2 is rearranged can be solved. Servo valves for high response hydraulic control can be adopted in the hydraulic piping of the lower decrease bending devices 7-3 and 7-4 deployed in the pair of second project blocks 5-3 and 5-4. This is because it is not necessary to use piping. For this reason, the recombination of the lower reinforcing roll 2-2 can be facilitated, and a roll bending apparatus with high responsiveness can be obtained.

Next, the rolling method according to the present embodiment will be described.
As shown in FIGS. 1 and 6, when the upper decrease bending devices 7-1 and 7-2 are provided in the upper reinforcement roll chock 4-1, when the upper reinforcement roll 2-1 is reassembled, the upper decrease bending device 2-1 It is necessary to attach and detach the hydraulic pipes 7-1 and 7-2, and there is a high possibility that minute foreign matters will be mixed in the hydraulic pipes when attaching and detaching.
For this reason, it is generally difficult to employ a servo valve for high response hydraulic control. In addition, in order to facilitate the attachment / detachment of the pipe, it is necessary to connect to each hydraulic control valve via a flexible and detachable hydraulic pipe such as a flexible pipe. In the case of adopting a flexible and detachable hydraulic pipe such as a flexible pipe, the fluctuation of the hydraulic pressure may be absorbed or alleviated because of the flexible structure.

Therefore, when the upper decrease bending devices 7-1 and 7-2 are installed in the upper reinforcing roll chock 4-1, the response of the roll bending device is less than when the fixed piping and servo valves are used. It must be lowered.
By the way, the decrease bending force cannot be applied during idling when no rolling load is applied. Therefore, when applying the decrease bending force, it is necessary to quickly set the decrease bending force from the idle state where the roll balance force is taken to the start of rolling, and to quickly return to the roll balance state at the end of rolling.
Therefore, if the roll bending force is changed by controlling the decrease bending device with poor responsiveness, a predetermined defect bending force may not be applied at the leading and trailing ends of the rolled material, and the shape defect portion may become long. There is.

The rolling method according to this embodiment solves the above problem.
That is, a rolling method using the

rolling mills

1 and 1 ′ according to this embodiment in which the upper decrease bending apparatuses 7-1 and 7-2 are arranged in the upper reinforcing roll chock 4-1, It is a rolling method that solves the above-mentioned problems that may occur.
As described above, in the

rolling mills

1 and 1 ′ in which the upper decrease bending apparatuses 7-1 and 7-2 are provided in the upper reinforcing roll chock 4-1, the response of the decrease bending apparatus may be deteriorated.
However, in the

rolling mills

1, 1 ′ according to the present embodiment, the upper increment bending apparatuses 6-1, 6-are provided on the pair of first project blocks 5-1, 5-2 projecting inward from the housing 9. 2 is a structure in which a large capacity and large stroke upper increment bending apparatus can be obtained.

Moreover, it is not necessary to attach or detach the hydraulic piping of the increment bending device every time the roll recombination work is performed, so that it is possible to adopt fixed hydraulic piping and servo valves, thereby making the incremental bending device highly responsive. it can.
The rolling method according to the present embodiment has a high responsiveness in changing the roll bending force at the start of rolling and at the end of rolling when the decrease bending force is applied to the work roll for the purpose of plate crown and shape control. This is performed by using an increment bending apparatus to compensate for the responsiveness of the decrease bending apparatus.

FIG. 7 is a diagram illustrating an example of an operation flow of the rolling method according to the present embodiment. That is, it is a diagram showing an operation flow of an increase bending device having a high response and a decrease bending device having a slightly lower response than the above.
FIG. 8 shows time-series changes such as roll bending force for one rolled material in this rolling method. FIG. 8 shows, from above, time series changes in the rolling load, the output of the increment bending apparatus, the output of the decrease bending apparatus, and the work roll bending force, which is the resultant force. Hereinafter, a description will be given with reference to FIGS.

First, before starting rolling, the set value FR of the work roll bending force during rolling corresponding to the rolled material to be rolled next is calculated and obtained. Here, it is assumed that FR is a negative value, that is, calculated as a decrease bending force. In this embodiment, the increase bending force (force in the increase direction (direction in which the roll R is opened)) is a positive value, and the decrease bending force (force in the decrease direction (direction in which the roll is pressed)) is negative. Value.

(First step)
Before rolling is started, both the increase bending force and the decrease bending force are applied, and the roll bending force on the increase side corresponding to the roll balance force FB is applied to the work roll chock as a resultant force.
That is, at idle before rolling, the increment bending apparatus output is IB (> 0), the decrease bending apparatus output is DB (<0), and IB + DB acts as the roll balance force FB (> 0).

The roll balance force FB is determined as a force that prevents the work roll driven by the electric motor and the follower reinforcing roll from slipping even in the idling state. At this time, the DB may be set with a minimum hydraulic pressure such that the actuator of the decrease bending apparatus does not leave the work roll chock.

(Second step)
Then, at a certain timing (point a on the time axis) before the start of rolling, a predetermined rolling bending device output DS sufficient to apply the work roll bending force FR during rolling is calculated by DS = FR-IR. To do. Then, DS and IS are simultaneously output so that the roll balance force FB is constant. Here, IR is the output of the increment bending apparatus during rolling, and a value close to the minimum controllable value is determined in advance so that the absolute value of DS does not become excessive. IS is the output of the increment bending apparatus where IS + DS = Fr. Therefore, at the set timing, the work roll bending force as the resultant force remains FB and does not substantially change.

(Third step)
Next, at the start of rolling, the increase bending force is changed (decreased) while maintaining the constant bending force at a constant value so that the predetermined work roll bending force FR during the rolling acts on the work roll chock as a resultant force. .
That is, at the start of rolling (b point on the time axis), the output of the increment bending apparatus is changed from IS to IR. As a result, the output of the slow bending device, which has a slow response, remains DS, and the work roll bending force as a resultant force is rolled from the roll balance force FB (> 0) by controlling the fast responding increase bending device. The work can be quickly switched to the roll bending force FR (<0).

Note that the rolling start time (b) refers to the time point when the rolling is started, and the detection is performed, for example, when the load detected by the load cell for measuring the rolling load of the

rolling mills

1 and 1 ′ is 30% of the expected rolling load. It can be decided by the method when it exceeds.

(4th process)
Then, the metal sheet is rolled while maintaining the roll bending force during the rolling.

(5th process)
At the end of rolling, in order to return the roll bending force to the state before starting rolling, a roll bending force corresponding to the roll balance force FB is applied to the work roll chock as a resultant force, and the rolling is finished.
That is, at the end of rolling (c point on the time axis), the output of the increase bending apparatus with a quick response is changed from IR to IS while the output of the decrease bending apparatus remains DS. By doing in this way, the work roll bending force as a resultant force can be quickly switched from the work roll bending force during rolling (FR (<0)) to the roll balance force (FS (> 0)).

Note that the end of rolling (c) refers to the end of rolling, and for example, the load detected by the load cell for measuring the rolling load of the

rolling mills

1 and 1 ′ is 50% of the average value of the actual rolling load. It can be determined by the method of timing below.

(Sixth step)
For example, the time when 1 to 3 seconds elapse from the end of rolling (c) is the work completion timing (point d on the time axis). At this timing, the output of the increment bending apparatus is set to IB, and the decrease bending apparatus. Change the output to DB. Even with this change, the work roll bending force as the resultant force is substantially maintained at the roll balance force FB.

As shown in FIGS. 7 and 8, in the rolling method according to the present embodiment, the roll bending force at the start of rolling and at the end of rolling is changed using an increase bending responsive apparatus. For this reason, even if it is necessary to deploy a decrease bending device having a relatively low response, a highly responsive increase bending device compensates for this. A shape control function can be provided.
Furthermore, even when the rolling force changes due to various factors (disturbances) during rolling, it is possible to quickly control to maintain the optimal work roll bending force with a highly responsive incremental bending device. It is.

That is, according to the rolling method according to the present embodiment, it is possible to build a good plate crown and shape against disturbances that vary during rolling, such as the rolled material entry side plate thickness and the rolled material temperature. Thereby, product quality and yield can be greatly improved.

FIG. 9 is a diagram showing a time series change of the roll bending force and the like when the response of the decrease bending apparatus is extremely low (particularly when it has a hydraulic characteristic in which the pressure decreases when the reaction force is released). Similarly to FIG. 8, according to the operation flow of the increment bending apparatus and the decrease bending apparatus shown in FIG. 7, changes in time series such as a roll bending force accompanying a rolling operation on a single rolled material are shown. That is, an example in which the response speed of the decrease bending apparatus is slower than in the cases of FIGS.
At timings b and c, the output of the increase bending apparatus with high responsiveness changes abruptly, so the output of the decrease bending apparatus with poor responsiveness fluctuates. As a result, the work roll bending force as the resultant force can be sent to reach FR at timing b, and it can be delayed to reach FB at timing c. The rolling method shown in FIG. 10 solves this problem.

FIG. 10 is a diagram showing an operation flow in the case of having an increase bending device with high responsiveness and a decrease bending device with low responsiveness. FIG. 11 shows time-series changes such as roll bending force for one rolled material in this rolling method. FIG. 11 shows the rolling load, the output of the increment bending apparatus, the output of the decrease bending apparatus, and the time series change of the work roll bending force, which is the resultant force, from the top. Hereinafter, a description will be given with reference to FIGS.
In the rolling method shown in FIG. 10, the decrease bending force or the hydraulic pressure in the hydraulic piping connected to the decrease bending apparatus is constantly measured by a load cell installed in the decrease bending apparatus, and the increment bending apparatus is based on the measured value. Dynamic control. That is, the output of the increment bending apparatus is controlled according to the decrease bending force or the hydraulic pressure of the decrease bending apparatus so that the work roll bending force becomes the roll balance force FB before and after rolling. In addition, although control other than this is the same as that of the rolling method shown in FIG. 7, it demonstrates concretely below.

First, before starting rolling, the set value FR of the work roll bending force during rolling corresponding to the rolled material to be rolled next is calculated and obtained.
(First step)
Before rolling is started, both the increase bending force and the decrease bending force are applied, and the roll bending force on the increase side corresponding to the roll balance force FB is applied to the work roll chock as a resultant force.
That is, at idle before rolling, the increment bending apparatus output is IB (> 0), the decrease bending apparatus output is DB (<0), and IB + DB acts as the roll balance force FB (> 0).

(Second step)
Then, at a certain timing (point a on the time axis) before the start of rolling, a predetermined rolling bending device output DS sufficient to apply the work roll bending force FR during rolling is calculated by DS = FR-IR. Then, the decrease bending force is changed from DB to DS. In addition, IS is an increase bending apparatus output determined by IS + DS = Fr, and is output simultaneously with Ds. Here, using the measured value DM obtained by measuring the decrease bending force momentarily (that is, continuously), the increment bending is performed so that the roll balance force FB that can be slightly changed is always constant. Control device output IS.

(4th process)
And rolling is performed while maintaining the roll bending force during the rolling. Here, using the measured value DM obtained by measuring the decrease bending force from moment to moment (that is, continuously), the roll balance force FB that can be slightly changed is always constant. The bending device output IR is controlled and output simultaneously with the decrease bending device output DS.

(6th process)
For example, the time when 1 to 3 seconds elapse from the end of rolling (c) is the work completion timing (point d on the time axis). At this timing, the output of the increment bending apparatus is set to IB, and the decrease bending apparatus. Change the output to DB. Here, using the measured value DM obtained by measuring the decrease bending force momentarily (that is, continuously), the increment bending is performed so that the roll balance force FB that can be slightly changed is always constant. The device output IS is controlled and output simultaneously with the DS.

By rolling with the rolling method shown in FIG. 10, as shown in FIG. 11, the increase bending device compensates for the fluctuation of the output of the decrease bending device, and the work roll bending force is optimized and high-response control is performed. Can be realized.
In addition, it is possible to predict the output fluctuation of the decrease bending device in advance and set the output of the increment bending device to compensate for it without the need for measurement of the bending bending force during rolling and feedback control by hydraulic pressure measurement. However, the same effect can be obtained.

When rolling at a roll opening degree exceeding the stroke of the first hydraulic cylinder, a roll balance force of the upper work roll 1-1 is applied by pulling the third piston rod, and then When rolling with a roll opening that does not exceed the stroke of the first hydraulic cylinder, by adopting the rolling method described above (from the first step to the sixth step), the same rolling mill can be used to produce a large piece of plate thickness. From rolling to hot-rolled sheet rolling that requires precise sheet crown and shape control can be handled.

The present invention can also be expressed as follows.
(1) A metal plate material rolling mill having a pair of upper and lower work rolls and a pair of upper and lower reinforcing rolls that respectively support the work rolls, and a hydraulic cylinder that applies an incremental bending force to each of the upper and lower work rolls. A rolling mill housing disposed in a project block projecting inwardly, and having a rolling direction force acting on the lower work roll supported by the project block, and a rolling direction force acting on the upper work roll being located above the project block A double-acting hydraulic cylinder that is supported by the window and gives the upper work roll decrease bending force is installed in the upper reinforcement roll chock, and its piston tip is connected to the upper work roll chock, and the upper reinforcement roll and the upper work Roll balance output that keeps the roll in contact Rolling mill of the metal plate having.
In this rolling mill, a hydraulic cylinder that applies an increase bending force to the upper work roll and a hydraulic cylinder that applies an increase bending force to the lower work roll are arranged at different positions on the plan view in the project block. May be.
In this rolling mill, a hydraulic cylinder for applying a decrease bending force to the lower work roll may be provided in the lower reinforcing roll chock or the second project block located below the project block.
In this rolling mill, the piston tip cross-section of the hydraulic cylinder that imparts the upper work roll decrease bending force has an enlarged portion, and the upper work roll chock has the enlarged portion moved by moving in the roll axial direction when the upper work roll is replaced. The recessed part to engage may be formed.
(2) A hot rolling method in which thick plate rolling is performed using the above rolling mill.
(3) When manufacturing the thick plate using the above rolling mill, when the roll opening exceeds the stroke of the hydraulic cylinder that gives the upper work roll increase bending force, the upper work roll decrease bending force is A hot rolling method in which the roll balance force of the upper work roll is imparted by a pulling operation of the hydraulic cylinder to be imparted.
(4) A hot rolling method in which rough rolling and / or finish rolling of thin plate hot rolling is performed using the above rolling mill.
(5) In the above hot rolling method, before starting rolling, both the increase bending force and the decrease bending force are applied, and the roll bending force corresponding to the roll balance force is applied to the work roll chock as a resultant force. After that, while changing the decrease bending force to become the decrease bending force during the predetermined rolling, the increase bending force is changed so that the combined force of the decrease bending force and the increase bending force maintains the roll balance force. Then, at the start of rolling, the increase bending force is changed as the resultant force while continuing the control of maintaining the decrease bending force during the predetermined rolling while maintaining the predetermined bending force during the rolling. Work roll chock During the rolling, the rolling is performed so as to maintain the predetermined work roll bending force during the rolling, and then the incremental bending force is changed at the end of rolling, and the resultant roll is combined with the decrease bending force. The roll bending force corresponding to the balance force is applied to the work roll chock, and the rolling of the metal plate material is finished in this state, and then the decrease bending force and the increase bending force are maintained so as to maintain the roll balance force as the resultant force. A method for rolling a metal sheet, wherein
In this metal sheet rolling method, the hydraulic pressure in the hydraulic cylinder that generates the decrease bending force or in the hydraulic piping connected to the hydraulic cylinder is measured, and based on the measured value, the roll bending force acting on the work roll chock is obtained as a resultant force. The increase bending force may be controlled to be a predetermined value.

The present invention relates to rolling of steel sheets, particularly as a reverse rolling mill that requires a large opening, and as a rolling mill that requires strong sheet crown and shape control, rolling mills ranging from extremely thick plate materials to thin plates. And a rolling method can be provided.

1-1 Upper Work Roll 1-2 Lower Work Roll 2-1 Upper Reinforcement Roll 2-2 Lower Reinforcement Roll 3-1 Upper Work Roll Chock 4-2 Lower Work Roll Chock 4-1 Upper Reinforcement Roll Chock 4-2 Lower Reinforcement Roll Chock 5- 1, 5-2 A pair of first project blocks 5-3, 5-4 A pair of second project blocks 6-1 On-side upper increment bending device 6-2 On-side upper increase bending device 6-3 On-inside lower Increment Bending Device 6-4 Outgoing Lower Increment Bending Device 7-1 Incoming Upper Debending Bending Device 7-2 Outgoing Upper Decrease Bending Device 7-3 Incoming Lower Decrease Bending Device 7-4 Outgoing Lower Decrease bending device 8-1 Entry side reinforcing roll balance device 8-1 Delivery side Strong roll balancing device 9 housing 10 metal plate 11 screw down device 12 housing window 31 groove

Claims

An upper work roll and a lower work roll for rolling a metal sheet;
An upper reinforcing roll and a lower reinforcing roll that respectively support the upper working roll and the lower working roll;
An upper work roll chock and a lower work roll chock that respectively support the upper work roll and the lower work roll;
An upper reinforcing roll chock and a lower reinforcing roll chock that respectively support the upper reinforcing roll and the lower reinforcing roll;
The upper work roll chock, the lower work roll chock, the upper reinforcement roll chock, and the lower reinforcement roll chock are accommodated, and a pair of first project blocks that project inward and bear the rolling direction force acting on the lower work roll A housing formed with a housing window bearing a rolling direction force acting on the upper work roll;
A first hydraulic cylinder provided on the pair of first project blocks and having a first piston rod for applying an increment bending force to the upper work roll via the upper work roll chock;
A second hydraulic cylinder provided in the pair of first project blocks and having a second piston rod for applying an increment bending force to the lower work roll via the lower work roll chock;
A third piston rod is provided on the upper reinforcing roll chock and has a third piston rod that applies a decrease bending force to the upper working roll or generates a roll balancing force by bringing the upper working roll into contact with the upper reinforcing roll. With a hydraulic cylinder;
A fourth hydraulic cylinder having a fourth piston rod for applying a decrease bending force to the lower work roll;
A rolling machine for a metal plate material.
2. The metal plate material according to claim 1, wherein the first hydraulic cylinder and the second hydraulic cylinder are provided at different positions on a plan view in the pair of first project blocks. Rolling mill.
The metal plate material rolling machine according to claim 1, wherein the lower hydraulic roll chock is provided with the fourth hydraulic cylinder.
The housing further comprises a pair of second project blocks projecting inwardly from the housing below the pair of first project blocks;
The rolling machine for metal sheet according to claim 1, wherein the fourth hydraulic cylinder is provided in the pair of second project blocks.
A first engaging portion is formed at the tip of the third piston rod;
2. The metal plate material according to claim 1, wherein the upper work roll chock is formed with a second engagement part in which the first engagement part is engaged by movement of the upper work roll in the roll axial direction. Rolling mill.
A method of rolling a metal sheet using the rolling machine according to any one of claims 1 to 5,
A rolling method of a metal plate material, wherein when rolling is performed at a roll opening degree exceeding a stroke of the first hydraulic cylinder, a roll balance force is generated by a pulling operation of the third piston rod.
A method of rolling a metal sheet using the rolling machine according to any one of claims 1 to 5,
When rolling with a roll opening not exceeding the stroke of the first hydraulic cylinder,
Before starting rolling, by causing both the increase bending force and the decrease bending force to act on the upper work roll and the lower work roll, a roll bending force corresponding to a roll balance force as a resultant force is applied to the upper work roll and the lower work roll. A first step that acts on the lower work roll;
A second step of increasing the increase bending force so that the resultant force maintains the roll balance force while changing the decrease bending force to a decrease bending force corresponding to the decrease bending force during rolling; ,
By maintaining the decrease bending force at the start of rolling and changing the increase bending force, a roll bending force corresponding to the roll bending force during rolling acts on the upper work roll and the lower work roll as a resultant force. A third step of
A fourth step of rolling while maintaining the roll bending force during the rolling;
At the end of rolling, by changing the increase bending force while maintaining the decrease bending force, a roll bending force corresponding to the roll balance force is applied to the upper work roll and the lower work roll as a resultant force. The fifth step of ending the rolling of the metal plate material in this state;
Thereafter, a sixth step of reducing the decrease bending force and the increase bending force so as to maintain the roll balance force;
A method for rolling a metal plate material, characterized in that:
At least one of the hydraulic pressure in the third hydraulic cylinder, the hydraulic pressure in the hydraulic piping connected to the third hydraulic cylinder, the hydraulic pressure in the fourth hydraulic cylinder, and the hydraulic pressure in the hydraulic piping connected to the fourth hydraulic cylinder. Continuously measured, and based on the measured value, the increase bending force acting on the upper work roll chock and the lower work roll chock as a resultant force is controlled to be a predetermined value, and the increase bending force is controlled. The method for rolling a metal sheet according to claim 7.
A method of rolling a metal sheet using the rolling machine according to any one of claims 1 to 5,
When rolling at a roll opening degree exceeding the stroke of the first hydraulic cylinder during rolling, a roll balance force of the upper work roll is applied by pulling the third piston rod,
Thereafter, when rolling at a roll opening that does not exceed the stroke of the first hydraulic cylinder,
Before starting rolling, by causing both the increase bending force and the decrease bending force to act on the upper work roll and the lower work roll, a roll bending force corresponding to a roll balance force as a resultant force is applied to the upper work roll and the lower work roll. A first step that acts on the lower work roll;
A second step of increasing the increase bending force so that the resultant force maintains the roll balance force while changing the decrease bending force to a decrease bending force corresponding to the decrease bending force during rolling; ,
By maintaining the decrease bending force at the start of rolling and changing the increase bending force, a roll bending force corresponding to the roll bending force during rolling acts on the upper work roll and the lower work roll as a resultant force. A third step of
A fourth step of rolling while maintaining the roll bending force during the rolling;
By maintaining the decrease bending force at the end of rolling and changing the increase bending force, a roll bending force corresponding to the roll balance force is applied to the upper work roll and the lower work roll as a resultant force. The fifth step of ending the rolling of the metal plate material in this state;
Thereafter, a sixth step of reducing the decrease bending force and the increase bending force so as to maintain the roll balance force;
A method for rolling a metal plate material, characterized in that:
At least one of the hydraulic pressure in the third hydraulic cylinder, the hydraulic pressure in the hydraulic piping connected to the third hydraulic cylinder, the hydraulic pressure in the fourth hydraulic cylinder, and the hydraulic pressure in the hydraulic piping connected to the fourth hydraulic cylinder. Continuously measured, and based on the measured value, the increase bending force acting on the upper work roll chock and the lower work roll chock as a resultant force is controlled to be a predetermined value, and the increase bending force is controlled. The method for rolling a metal sheet according to claim 9.