JPS5823508A - Rolling mill having shape controlling function - Google Patents

Abstract

PURPOSE:To make lateral rigidity optimum and to make the shape of a material to be rolled excellent, by changing the offset quantity of a working roll by a supporting roll. CONSTITUTION:When a signal of the sheet width of a material to be rolled is sent to an offset-quantity operator 25 after setting the sheet width to a sheet- width setter, an equivalent lateral rigidity optimum to the sheet width is computed by the operator 25. Further the offset quantity is computed, the results of which is sent to a servo-valve 21, and the fluid from a fluid pump 20 is sent to a hydraulic-pressure cylinder 16 while its flow rate being control by the valve 21. A rod 17 of the cylinder 16 is advanced and retreated by the fluid to change the offset quantity of an upper working roll 12. The quantity of advancing and retreating of the rod 17 as detected by a sensor 22, and the results are sent to a comparison operator 23 to stop the movement of the rod 17 by closing the valve 21 when the difference between the results and a signal outputted from an offset quantity operator 25 reaches zero. Accordingly, rolling is performed in an optimum condition of the lateral rigidity of a mill.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rolling mill having a mechanical shape control device.

The lateral rigidity of a rolling mill is a concept that represents the deflection in the roll width direction due to rolling force, and is defined by the following formula.

Here, PR: rolling force TON CR: plate crown mm Since the lateral rigidity Q of this rolling mill changes depending on the plate width, it is difficult to appropriately determine the relationship between rolling force PR and roll pending force Pa.

If the lateral stiffness of the rolling mill can be maintained at an optimal value regardless of the strip width, the strip crown can be minimized against rolling force disturbances.

The present invention has been made in view of this point of view, and includes a work roll in which one of the upper and lower work rolls is offset with respect to the longitudinal direction of the rolled material with respect to the backing roll, and the length is shorter than the work roll and offset. A support roll that pushes the work roll in the longitudinal direction of the rolled material by a drive device is provided, and a coefficient setting device that provides arbitrary lateral stiffness is provided, and a natural The present invention is characterized in that it includes a calculator that calculates an offset amount from the value of the lateral stiffness coefficient, and a device that calculates the offset amount and controls the drive device.

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

First, the principle of the present invention will be explained.

As shown in Figure 1, when offset roll (1) is pushed horizontally by t-narrow roll (2), the central part of offset roll (1) gives vertical displacement to rolls (3) and (4). At the same time, both ends of the offset roll (1) rise somewhat along the outer periphery of the roll (3) as shown in FIG.

The displacement ΔR due to this rise can be expressed as follows from the geometrical relationship shown in FIG.

In other words, the offset roll (
R1 is the distance from the center of the displacement part of 1), R2 is the distance from the center of the roll (4) to the center of the displacement part of the offset roll (1), and R2 is the distance from the center of the roll (3) or (4) to the center of the offset roll (1). The vertical distance to the center of the non-displaced portion of
y1 If the displacement in the horizontal direction in this case is Δe, then R1"=("+4g)"+(y-Δ3/)2・"-"-
”(i)R,”:=(g+Δg)”+(3′+Δy)
2・・・・・・・・・−(ii), (ii) −(+
) from R2" - R1" = (Rt - Rt) (R2 + Rt) =
(y+Δy)2-(y-Δy)2=4yΔy...011).

However, if the radius of rolls (3) and (4) is rl, and the radius of offset roll (1) is r2, then R, = r
, +, 7. Since it is expressed as +ΔR r, +7′, := R=Rt, the set of R2=ΔR% Rz +R1=2R.

Therefore, the equation 011) becomes ΔR·2R=4yΔy, and while this Δy=−Jg, the displacement position ΔR becomes y.

On the other hand, when a rolling force PR is applied to the rolling mill roll shown in Fig. 1, a horizontal component force P is applied to the offset roll (1).
, becomes Pl=PR5iFLα=Pn (here, α is the angle that the offset roll (1) makes with respect to the vertical line). Therefore, as shown in Figure 3, the offset roll (1) supports both ends of the narrow-mouth roll (2).
Here l is the total length of the offset roll (1)).

The deflection δ of the beam at an arbitrary X position is expressed by δ.

It is expressed as δ=Wβ′ (where β is the deflection coefficient).

Also, since δ=Δe, Wβ=Δe, which can be expressed as -
When inserted into the φ formula, we get the following.

Generally, for plate crowns It is expressed as

Here, CR: control crown amount to control plate crown Q: Natural lateral stiffness Also, since On is a value that can be controlled by the offset amount cR = upper - β 8　　　　　　　　・・・・・・・・・・・・・i).

from, From the 00 formula and the cyiiD formula, is obtained.

-A stiffness), then A = 1 and Qeq = (capital) A = 0.5 TeQt9 = 2Q A=0 and Qeq=.

As such, Qgq is variable.

Therefore, in order to give the required A or Qeq to the rolling mill, It can be seen that it is sufficient to give the offset position e as shown below.

Therefore, in order to obtain the required lateral rigidity, it is sufficient to change the offset amount e.

Next, a fourth embodiment of the present invention, which is realized based on the above principle, will be described.
This will be explained with reference to the drawings and FIG.

In the figure, 01) is the rolling mill housing, 03 is an upper work roll with a small diameter and offset in the longitudinal direction of the rolled material, α is the lower work roll, and 04) is centered on a perpendicular line passing through the center of the lower work roll 03. 05 is a lower backing roll whose center is on the perpendicular line.

A fluid pressure cylinder aO that can move the rod On in the longitudinal direction of the rolling material ■ is attached to the rolling mill housing aυ, and the upper work roll is attached to the shaft box 08 attached to the rod On of the hydraulic cylinder am. A support roll holder shorter than the length of 03 is pivotally mounted, and the upper work roll 02 can be pushed and pulled in the longitudinal direction by the support roll 09, and a servo valve Qυ connected to the fluid pump holder is installed.
is connected to the chamber of the fluid pressure cylinder αe, a sensor (2) for detecting the amount of movement of the fluid pressure cylinder θe is connected to the comparison calculator (c), and an offset amount calculator (c) is connected to the plate width setting device Q4. Connect C) to the comparator (C),
The comparator Q3 is connected to the servo valve (20).

In the figure (c) is the offset amount calculation Mf! This is a lateral stiffness coefficient setter connected to 3.

When the plate width B of the rolled material ■ is set in the plate width setter Q4 and the signal of plate width B is sent to the offset amount calculator (c), the offset amount calculator (c) calculates the equivalent lateral stiffness that is optimal for the plate width. Qeq is calculated as a function of the plate width using the formula Qeq=f(B), and this result is used as the length 11 of the upper work roll 0, the deflection coefficient β, and the upper work roll set in advance in the offset amount calculator (c). roll 03
Based on the distance R between the center and the center of the upper hold-down roll (14), the offset amount - is calculated using equation (2), and the result is sent to the servo valve (20) to reduce the flow of fluid from the fluid pump (to). is sent to the fluid pressure cylinder Oe while the flow rate is controlled by the servo valve (2D), and the rod of the fluid pressure cylinder Q6 is moved forward and backward by the fluid, changing the amount of offset of the upper work roll 03.The rod (17) moves forward and backward. The amount is detected by the sensor @ and sent to the comparator (c), and if the difference with the signal from the offset amount calculator (c) becomes zero, the servo valve Qυ
is closed and rod a'7) stops moving. Therefore, rolling can be performed with the lateral rigidity of the rolling mill being optimal.

In addition, in the embodiment of the present invention, a case has been described in which the optimally set lateral stiffness is calculated based on the board width, but it is possible to determine the lateral stiffness based on the board width in advance and set the lateral stiffness based on the board width. Of course, the roll to be offset may be a lower work roll instead of the upper work roll, and various other changes may be made without departing from the gist of the present invention.

According to the rolling mill of the present invention, the lateral rigidity can be optimized by changing the amount of offset of the work rolls using the support rolls, so that the shape of the rolled material can be improved.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the arrangement of rolls to explain the principle of the rolling mill with shape control function of the present invention, and Fig. 2 shows the geometrical relationship of the rolling mill with shape control function of the present invention. FIG. 3 is an explanatory diagram showing the load distribution state in the principle of the rolling mill having the shape control function of the present invention;
5 is an explanatory diagram of a rolling mill having a shape control function according to the present invention, and FIG. 5 is an explanatory plan view of the rolling mill having a shape control function shown in FIG. 4. In the figure, aυ is the rolling mill housing, α is the upper work roll, 0
Q is the lower work roll, Q[f] is the fluid pressure cylinder, a is the support roll, Qυ is the servo valve, (221 is the sensor,
C3 is a comparison calculator, (24) is a plate width setter, (2S is an offset amount calculator, and (A) is a lateral stiffness coefficient setter. Patent applicant Ishikawajima Harima Heavy Industries Co., Ltd. Figure 1 Figure 3

Claims (1)

[Claims] 1) Offset one of the upper and lower work rolls with respect to the longitudinal direction of the rolled material with respect to the backing four, and drive the offset work roll that is shorter than the work roll in the longitudinal direction of the rolled material using a drive device. A support roll that pushes in the direction is provided, a coefficient setting device that gives an arbitrary lateral stiffness, and the offset amount is determined from the coefficient determined by the coefficient setting device and the value of the natural lateral stiffness coefficient determined by the roll diameter and the plate width. A rolling mill having a shape control function, characterized in that it is provided with a computing unit for computing and a device for computing one offset amount and controlling the drive device.