JPS5858919A - Controller for continuous rolling mill - Google Patents

Abstract

PURPOSE:To roll products smoothly with high dimensional accuracy by detecting the breadth sizes, etc. on the outlet side of the i stand of continuous rolling mills, and controlling the material tension between i-i-1 and between i-1-i-2. CONSTITUTION:In continuous rolling mills having calibers, the breadth of a material is detected with a breadth size detector 32 on the outlet side of an (i) stand 4, and the deviation from a reference breadth is inputted to a speed controller 34, which controls the rolling speed of the stand 4 thereby controlling the material tension between the i-i-1 stands 4-3. The deviations between the height size detected with a height size detector 31 and a reference height size is inputted to a shape correcting device 35, which calculates the change value of the height size according to prescribed algorithm. The draft position is controlled by the controller 36 for rolling reduction of the i-1 stand 3. The value of tension control is further inputted to the device 35 to correct the draft position by the controller 36. According to the change value of the breadth size calculated by the device 35, the tension between the stand 3 and the i-2 stand is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a continuous rolling mill having a hole shape, such as a steel bar rolling mill.
A device that controls the dimensions of rolled material in a wire rod rolling mill, etc. f
ζ related.

An example of the configuration of a continuous rolling mill having a hole shape is shown in FIG.

Figure 1 shows a continuous rolling mill consisting of i-stands: (1) is the #1 stand rolling mill, (2) is the #2 stand rolling mill, and (3) is the #-1-1 stand rolling mill. ,(4)
is the #i stand rolling mill, and (5) is the rolled material. In addition,
In this example, a so-called VH type rolling mill is assumed, so vertical rolling mills (odd-numbered stands in Figure 1) and horizontal rolling mills (even-numbered stands in Figure 1) are arranged alternately. There is.

For example, the #i-1 Me 1 stand (3) is a vertical rolling mill that performs rolling in the X direction. Here, bi-1 is i
-1 stand rolling mill (3) Width dimension at the exit side, to-+ represents the vertical dimension. Also, #11 stand rolling (4)
is a horizontal rolling mill that performs rolling in the Y direction.

Here, bl represents the width dimension at the exit side of the i-stand rolling mill (4), and hi represents the dimension in the vertical direction.

Conventionally, continuous rolling mills such as bar and wire rod rolling mills have adopted zero-tension control (AMTC) to control the tension between stands to zero, but those that attempt to dynamically control the dimensions of the rolled material have There were none. The reasons for this are: (1) Extremely strict product dimensions were not required.

(2) The elongation of the mill due to load fluctuations during rolling is small.

(This fact reduces the effect of transmitting fluctuations on the input side of the rolled material to the output side, improving the accuracy of product dimensions.)

Since there is no control over dimensional fluctuations due to changes in size, there is a drawback that dimensional accuracy deteriorates.

The present invention has been made in view of the above drawbacks, and detects the width dimension of the material exiting from the i-th stand, and detects the width dimension of the material exiting from the i-1st stand and the fifth stand so that the deviation from the standard width dimension is zero. The purpose is to control the material tension between the two and to perform rolling with high dimensional accuracy. In addition to controlling as described above, the dimension change value of the r-1 stand is calculated, the rolling position of the i-1 stand and the material tension between the i-2 stand and the i-1 stand are controlled, and the dimensions are The purpose is to perform smooth rolling with high precision.

FIG. 2 shows an embodiment of the present invention.

In Figure 2, (3) is the i-1 stand rolling mill, (4
) is an i-stand rolling mill, (5) is a rolling mill, (7) +
(s) is the motor for lowering each stand, (9) l 0
0 is a load cell that is attached to each stand and detects the rolling load, ``0υ'' (Y is the rolling drive motor (7)
r'a) is connected to a pulse transmitter for detecting the rolling position, (to), 04 is the rolling driving motor (7), (8)
A motor-driving sleep star device that supplies electric power, O1
2,01 is the mill rigidity control device of each stand, (2) is i
- Motor for driving the rolling rolls of the 1-stand rolling mill (3), (2) is the motor for driving the rolling rolls of the 1-stand rolling mill (4), (to), 1241 is the drive of each motor (2), @ The cyrisk device, (e), is the handle the drive motor? p
.

f311 is the speed detector that detects the speed of the i-stand rolling machine (4) the vertical dimension detector that detects the vertical dimension of the exit side material, □□□ is the i-stand rolling machine (4) the vertical dimension detector that detects the vertical dimension of the exit side material This is a width dimension detector that detects width dimensions. The deviation Δb between the width dimension bi detected by the width dimension detector and the standard width dimension 1) i IKF at the exit side of the i stand is input to the speed control device diagram, and the rolling speed of the i stand is controlled. .

Also, the vertical dimension h detected by the vertical dimension detector (3I)
The deviation ΔYu between i and the reference vertical dimension 11Limy on the exit side of the i stand is supplied to the shape correction device (to). (To) is a shape correction device, and the dimensional variation △hi of the material on the exit side of the i-stand
1 Input Δb and the control output ΔVi of the speed control device (incorporated), and according to the predetermined algorithm, set Δbi- to zero and set tH- to the vertical dimension change value of i-1 stand rolling mill (3). and the width dimension * A shape correction device that derives the vertical dimension change value Δb1-1, and a rolling down control device that corrects the rolling position of the i-1 stand according to the vertical dimension change value Δhi-1 derived by the shape correction device of - , (3η is the width dimension change value △Au1 derived from the shape correction bag m (to)) is a speed control device for correcting the speed of the drive motor of the i-1 stand. A control method in one embodiment will be described.

First, in the present invention, the rolling speed of the i-stand is controlled in order to control the width dimension of the material exiting from the i-stand rolling mill (4), and the reason for this will be described.

Figure 8(a) shows the rolling position sI of the i-stand rolling mill (4).
It shows the variation in the vertical dimension h1 and the width dimension of the rolled material (5) on the exit side of the i-stand rolling mill (4) when changing the speed of the i-stand rolling mill (4). ΔVR/V
Between i-1 stand and i stand when changing R
It represents the variation of the tension α and the rolled material on the exit side of the i-stand rolling mill (4) (5), the vertical dimension h (and the width dimension bi). Even if the speed of is changed, the vertical dimension hi hardly changes and the width dimension b1
only changes. Therefore, in order to change the vertical dimension hi on the exit side of the i-stand rolling mill (4), as shown in FIG.
need to be controlled.

However, since the width dimension bi also changes if the rolled down position S1 of the i-stand is controlled, it is not possible to simply control the rolled down position S1. On the other hand, as shown in FIG. 8(b), even if the width dimension of the material on the exit side of the i-stand is controlled by controlling the rolling speed ΔVR/VR of the i-stand, the vertical dimension h
1 has almost no effect.

Therefore, when controlling the width dimension, it is sufficient to control the speed of the i-stand and the tension between the i-1 stand and the i-stand.

That is, the deviation Δb between the width dimension detected by the width dimension detector (32) installed on the exit side of the i-stand rolling mill (4) and the standard width dimension bi IIEν of the i-stand exit side is determined by the speed control device. In the speed control device, the speed correction signal ΔvI is inputted based on the relationship shown in FIG.
4 to the device that generates and drives the i-stand rolling mill (4).
The speed correction signal ΔVi generated by No. 1 is input to the thyristor device together with the speed reference signal Ni RRy of the i-stand. The thyristor device controls the speed of the motor (2) according to the input speed signal. This speed control is continued until the feedback signal from the speed detector matches the speed signal input to the thyristor device.

Now, the speed of the i-stand is corrected as described above by the speed control device (incorporated), but if the amount of correction is large, i-1
The tension (or compressive force) between the stand and the i-stand becomes excessive, and there is a risk that the rolled material (5) will not be constricted or buckled. In order to prevent this, the dimensional deviation △)11+△bi and the i-stand speed correction amount △Vi of the rolled material on the exit side of the i-stand are input to the i-1 stand shape correction device (to), and the In order to change the shape of the material, reduction correction and speed correction are applied to the reduction control device aT24 and speed control device βη of the i-1 stand.

The operation of the i-1 stand shape correction device (to) will be explained.

The i-1 stand shape correction device (to) is inputted with the dimensional fluctuations Δhi and mu bi of the rolled material on the outlet side of the i-stand rolling mill (4), and the i-1 stand * such that these fluctuations become zero is input. The vertical dimension change value Δh11+width dimension change value Δbi-1 of the rolled material on the exit side is calculated. Various forms of this calculation algorithm can be considered depending on the characteristics of the rolling mill, and here, two typical sides will be described below, but it is not limited to this.

As an example of the calculation algorithm, the i-1 stand exit vertical dimension *
* Law change value △lli 1
+ Calculate width direction dimension change value Δbi-1.

This is the influence coefficient of the method change on the top and bottom dimensions of the rolled material on the exit side of the i-stand.

αb1 is the influence coefficient of the vertical dimension change of the rolled material on the exit side of the i-1 stand on the width dimension of the rolled material on the exit side of the l stand.

This is the influence coefficient on the width dimension of the rolled material at the exit side of the l stand.

As another example of the calculation algorithm, when both the i-1 stand mill rigidity and the i-stand mill rigidity are sufficiently high, and the vertical dimension variation Δhl is not large, and therefore the reduction change amount ΔSi is not large, the i-1 stand exit side The shape correction is performed by controlling the width direction dimension variation Δbi to zero. At that time, △bi will change even if either of the 1-1 stand exit side rolled material dimensions hi and bi are changed, but the ratio of each change amount α = tAII-1/Δ1)i-1 will be a constant value. Control as follows. The amount of change Δ11i1+Δbi−1 is derived below.

△hi-t=α・Δbj-1・・・・・・・・・・・・
(7) Substituting equation (7) into equation (6), ΔI)i−1
After calculating the number of command values, the sign of the command value is reversed and the change amount Δbil is obtained by formula 8) + the change amount △)l is obtained by formula 8)
Calculate i-1.

* If α=0 at this time, the ellipticity will be constant with only a change of Δb1-1.

The operating timing of the i-1 stand shape correction device is 1
Stand pressure correction amount M1, 1 stand speed correction amount △V
+ may be monitored and activated only when this exceeds a limit value, or it may be activated at all times regardless of the values of ΔSI and ΔVl. Next, the outputs k11 and Δbl 1 from the i and -1 stand shape correction devices mμs are the S-t stand pressure control device trowel and the i-1 stand speed control device ct71, respectively.
is input.

The reduction control device of the i-1 stand calculates the amount of reduction change based on Δhi-1 using equation (9).

iLi where αh i-1/(XS i-1 is the influence coefficient of the i-1 stand reduction change amount on the vertical direction dimensional variation of the rolled material on the exit side of the i-1 stand.

*In addition, the speed control device of i-1 stand is Δt)
Based on i-1, the speed change amount ΔV,/ is calculated using equation (6).

△V, El= 1, △b+-1...
Song 0Qdb 1-1- Review where abi 1 is i-1 stand speed change amount
αvi-1 Influence coefficient on width direction dimensional variation of rolled material on exit side of stand.

Next, when changing the reduction, the exit width dimension also changes, so the speed -
− Here, 51・”6 is (υ, the influence coefficient α5 shown in equation (2)
i-1αV1-1 This relates to the i-1 stand of number.

Using the sum of both ΔVl-4 and Δvi-1 as the To1 negative stand speed correction book ΔVt-t, the i-1 stand speed and the i-stand speed are corrected, and the i-1 stand forward tension is changed.

In the above manner, i-1 stand exit side shape correction*
*The reduction and speed of the i-1 stand are corrected so that the output value to the device is Δhhi1+411.

By the way, in order to control the i-1 stand, it is necessary to make a decision by the influencer, but it can be measured once the rolling schedule is decided, and even if there is some error,
Feedback control is performed by a dimension detector on the exit side of the i-stand, so there is no error in the final dimensions and shape.

In the above embodiment, a vertical dimension detector 1311 is installed on the exit side of the i-stand rolling mill (4), and the vertical dimension fluctuation Δh1 of the material on the i-stand exit side is inputted to the shape correction device (toward). It is assumed that the vertical dimension change value Δhi'i and the width dimension change value 1) i-1 of one stand are calculated, but the vertical dimension detector 01) is omitted and the shape correction device 3 is used to calculate the width dimension change. △b, and the control amount △Vi of the speed control device
*11i-1 and bi-1 may be calculated.

In addition, in the above embodiment, in order to change the tension between the i-2 stand and the i-s stand, ll, the speed of the l stand, and i-
Although the speed of the i-stand was changed to change the tension between the 1-stand and the i-stand, the speed of the i-2 stand and the speed of the 1-2ri-1 stand may also be changed.

The key is the tension between the i-2 stand and i-1 stand and the i-1
It is sufficient if the tension between the stand and the i-stand can be controlled.

In addition to the above, according to the present invention, the width dimension of the material on the outlet side of the first stand is detected, and the material tension between the S-th stand and the i-th stand is adjusted so that the deviation from the reference width dimension is zero. Since it is controlled, rolling can be performed with high dimensional accuracy. Further, while carrying out the above control, the vertical dimension change value and the width dimension change value of the i-1th stand are derived so that the width dimension variation on the exit side of the i-th stand is zero.
The lowered position of the 1st stand and the i-2nd stand and the i-th stand
Since the material tension between the stands is controlled,
Rolling can be carried out smoothly and with high dimensional accuracy without constricting or buckling the rolled material.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a configuration example of a continuous rolling mill having a hole shape, Fig. 2 is a block diagram showing a dimensional control device in a continuous rolling mill according to an embodiment of the present invention, and Fig. 8 (a ), (b
) is the vertical dimension relative to the rolling position and speed of the rolling mill, 411
FIG. 3 is a characteristic diagram showing the relationship between jC dimensions. In the figure! 3) t (4) is a rolling mill, (7L (
8) is the reduction drive motor, (0), GO is the load (Z
Jl/, Q3, (Irisk device from 14, C4, l-241i, 0 weight) is the vertical dimension detection device, atZ is the width dimension detection device, 1341. t371 is a speed control device, (to) is a shape correction device, and 2 is a reduction control device. In each figure, the same reference numerals indicate the same or corresponding parts. Agent Makoto Kuzuno - No. 1 31#2 1 Figure t'-t: 4 bt'-t"l- ((12) Figure 3 tb) ♂

Claims (2)

[Claims] (1) In a device for controlling a continuous rolling mill having a hole shape, a width dimension detector for detecting the width dimension bi of the material/material on the exit side of the i-th stand rolling mill, a detected value of this width dimension detector, + , a reference width dimension bIRIF, and a deviation Δbi, and a device for controlling the tension between the i-1 stand and the i-th stand so that the deviation becomes zero. . (2) In a device that controls a continuous rolling mill having a hole shape, a width dimension detector detects the width dimension bi of the material on the exit side of the i-th stand rolling mill, and the detected value b1 of this width dimension detector and the reference width dimension A first device that inputs bIIIF and the deviation 6 stones, and controls the tension between the i-1 stand and the i-th stand so that the deviation becomes zero, the control output of this first device, and the width dimension deviation △ With b1 as input, the sky * of the i-1st stand such that Δbi is zero
* A shape correction device that calculates a ground dimension change value hi-1 and a width dimension change value 1) i-1 according to a predetermined algorithm; A rolling control device that controls the rolling position of the one-stand rolling mill, and a second device that controls the tension between the i-2nd stand and the i-1st stand according to the width dimension change value k) i-1 calculated by the shape correction device. A control device for a continuous rolling mill, characterized in that it is equipped with a device.