JPS60148615A - Control device of rolling mill - Google Patents

Abstract

PURPOSE:To prevent automatically the meandering of a material to be rolled and to improve the productivity and quality of a product by controlling the exit- thickness deviation quantity, computed basing on the exit-thicknesses at the driving and working sides of a mill, to be a previously-set target value. CONSTITUTION:The exit thicknesses hD, hW at the driving and working sides of a mill 10, are respectively computed by a gauge meter system basing on rolling loads PD, PW and roll gaps SD, SW at respective sides. The thicknesses at respective sides at an optional point of time when the rolling is stabilized after biting a material to be rolled, are stored, as the reference values of lock-on timing, in storage devices 33, 43. Respective deviations DELTAhD, DELTAhW between the stored reference values and the exit-thicknesses at respective sides are obtained, to express it as an exit-thickness deviation-quantity DELTAh. Then the roll gaps at respective sides of mill 10 are controlled so that this quantity DELTAh coincides with the exit- thickness deviation quantity, set previously by an experienced side.

Description

[Detailed Description of the Invention] (2) [Technical Field of the Invention] The present invention relates to a control device for a rolling mill, particularly in a rolling mill that rolls metal such as a hot rolling mill, when rolling a material to be rolled in the thickness direction. The present invention relates to a control device for a rolling mill that can automatically adjust meandering that occurs in rolling mills.

[Technical background of the invention and its problems]

When performing hot rolling etc. in a rolling mill, the rolling opening degree may be different between the drive side and the work side, or the material to be rolled may slip from the roll center in the direction of the roll axis. . FIG. 1(a) is a cross-sectional view of the rolling roller.
2 is a rolling roll, and 2 is a material to be rolled. SD and SW are the reduction opening degree, pD, and pw on the drive side and work side, respectively.
are the load and weight on the drive side and work side, respectively. SW
>SD, the protrusion thickness hW of the workpiece side of the rolled material 2 is larger than the protrusion thickness hD of the drive side. Therefore, the advance rate fD and reverse rate bD on the drive side are the advance rate fw on the work side,
It becomes larger than the backward movement rate bW. These relationships are shown in FIGS. 1(b), (c), and (d), respectively. As a result, the rolling material speed is faster on the work side than on the drive side, and conversely, the rolling material speed is slower on the work side than on the drive side. In this way, the material to be rolled winds toward the workpiece side as shown by arrow A on the personnel side and material side of the rolling mill.

Generally, the material to be rolled is placed in such a way that the center of the material 2 is aligned with the center of the rolling roll 1 by side guides on the personnel side of the rolling mill.
If the center of the rolled material 2 deviates from the center of the rolling roll 1, there will be a difference in the rolling reaction force received by the drive side and the work side, so Sw = SD is set. Even if Sw'
ySn, and meandering occurs in the same process as described above.

Since the cause of the meandering described above was previously unknown, automatic control can be performed. Conventionally, an operator manually performed one-sided rolling based on experience and continued rolling. However, in such manual correction, the corrective action is not accurate and the corrective amount is not accurate, resulting in accidents such as the rolled material colliding with the side guide, resulting in quality and operational problems.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a control device for a rolling mill that can automatically prevent meandering of a material to be rolled.

[Summary of the invention]

The feature of the present invention is that the thickness of each side is calculated using a gauge meter method based on the load and rolling opening of the drive side and workpiece side of the rolling mill, and lock-on is performed at any stable point after the rolled material is bitten. As a timing, memorize the protrusion thickness of each side at that time as a reference value, calculate the deviation between the reference value of each side and the protrusion thickness of each side, and update the difference between the deviations of each side. By controlling the rolling opening on each side of the rolling mill so that the amount of deviation in thickness from □ becomes the standard for deviation in thickness, which is set in advance according to empirical rules, the material to be rolled is meandering. The goal is to automatically control the situation so that it does not occur.

[Embodiments of the invention]

The present invention will be described in detail below based on a block diagram of an embodiment shown in FIG. Drive side rolling opening degree SD of the rolling mill 10
The load PD is input to the drive side protrusion thickness calculating device 31, and the drive side protrusion thickness hD is calculated using a gauge meter method. The switch 32 instantly turns O at the lock-on timing.
With this switch, the drive side protrusion thickness hnr (drive side protrusion thickness lock-on value) at the lock-on timing is recorded in the storage device 1:3g. The subtractor 34 subtracts the drive side thickness hD and the drive side thickness lock-on value hDL, and the drive side thickness deviation △
hD is calculated.

On the other hand, work side rolling opening Sw and load PW of rolling a10
is input to the workpiece side protrusion thickness @ end device 41, and the workpiece side protrusion thickness hW is calculated by a gauge meter type. Switch 42
is a switch that turns on instantly at lock-on timing.
As a result, the workpiece side protrusion thickness hwL (workpiece side protrusion thickness lock-on value) at the lock-on timing is stored in the storage device 43.
A zero subtractor 44 stored in the subtractor 44 subtracts the workpiece side protrusion thickness hw and the workpiece side protrusion thickness lock-on value hWL, and calculates the workpiece side protrusion thickness deviation Δhw.

Drive side thickness deviation △hD to workpiece side thickness deviation △h
W is subtracted by the subtractor 45, and the amount of thickness deviation Δh is calculated. This thickness deviation amount Δh is inputted between the control and arithmetic units. First, in the subtracter 51, the reference thickness deviation amount Δhr
The amount of deviation in thickness △h is subtracted from ef, and the deviation in thickness δ is obtained.
h is output. This protrusion thickness deviation amount deviation δh is calculated by the conversion device 5
2, it is converted to the reduction opening degree deviation △So, and PID
The controller 53 inputs this roll-down opening deviation amount ΔSo and calculates the roll-down opening correction amount δSo.◇The calculator 54 calculates the roll-down opening correction amount δS.

As input, drive side reduction opening correction value δS,p,re
f is calculated, and from this value, the work side pressure upward opening correction amount δSw+ref is calculated by the sign inverter 55. These reduction opening correction amounts δSD+ref and δSW+ on both sides
r8f is input to the hydraulic position control side units f61 and 62 on both sides, respectively, and the rolling 11100 is set as the drive side rolling opening adjustment value δSD and the work side rolling opening adjustment value δSW.
The operation of the control system configured as above, which controls the rolling opening degree on both sides and the meandering of the material to be rolled, will be described in detail below. Drive side protrusion thickness hD and workpiece protrusion thickness hw
are calculated by the drive side protrusion thickness calculation device 3 and the workpiece side protrusion thickness calculation device 41 based on the gauge meter formulas shown in equations (1) and (2), respectively.

Here, 81) Nidrive side rolling opening Sw: Work side rolling opening PD Nidrive 11411 load Pw: Work side load MD Nidrive side mill constant Mw: Work side mill constant gD Nidrive side roll deflection correction coefficient gw: This is the work side roll deflection correction coefficient. The roll deflection correction coefficient is a coefficient for correcting changes in the deflection rolling opening degree of the rolling mill rolls due to the rolling pressure of the material to be rolled.

The drive side protrusion thickness lock-on value hDL and workpiece side protrusion thickness lock-on value hWL at the lock-on timing after the rolled material is bitten by the rolling mill ζ are calculated by formula (3) and formula (4), respectively.
).

Here, SDL Nidrive side lock-on compression opening degree 5VIIL
: Work side lock-on reduction opening degree PDL Nidrive side lock-on load PwI, : Work side lock-on load. The drive side protrusion thickness deviation ΔhD and the workpiece side protrusion thickness deviation Δhw after the long lock-on timing are expressed by equations (5) and (6), respectively.

△h,, = hDhDL ・・・・・・・・・・・・
・・・・・・・・・ (5) Δhw= hw hwx,
・・・・・・・・・・・・・・・・・・・・・ (6)
The cause of the meandering of the rolled material is due to the difference in the thickness deviations ΔhD and ΔhW on both sides. Therefore, the thickness deviation so Δh corresponding to this difference is calculated using equation (7).

△h=ΔhD−Δhw ・・・・・・・・・・・・・・・
(7) Therefore, in order to prevent meandering of the rolled material, control is performed so that the thickness deviation cover Δh becomes the thickness deviation reference Δ1lref. For this reason, the output thickness deviation δh is calculated using equation (8).

δh=Δhref−Δh・・・・・・・・・・・・・・・
(81) Here, the thickness deviation standard Δhr
ef is a constant determined empirically depending on the plate thickness, plate width, steel type, and rolling mill of the material to be rolled.

The deviation δh of the thickness deviation is calculated by the equation (9) by the conversion device t52, and is calculated as the reduction opening deviation amount ΔS.

is converted to

△So=ni,・δh ・・・・・・・・・・・・・・・
(9) Here, 1 is a constant determined by the mill constant of the rolling mill and the plasticity coefficient of the material to be rolled.

1) The ID controller 53 is a controller that performs normal proportional, integral, and differential operations, and is a controller that performs normal proportional, integral, and differential operations.
The reduction opening correction amount δS is obtained by calculating the formula a.

get.

Here, 'r, + 'r* l rp, : constant 8 nila plus operator.

When the reduction opening correction amount δSo is added to either side, the average thickness of the rolled material changes. Therefore, in order to keep the average thickness unchanged, the reduction opening correction amount is divided into separate amounts for both sides, and is added to one and decreased to the other. That is, the calculation unit 55 and the sign inverter 56 calculate the drive side reduction opening correction amount δSD, . f, δSW, and ref are calculated by the equation Uυ and the equation αa, respectively.

δsw, ref −−−・δSo・・・・・・・・・
... σa Finally, the reduction opening adjustment lid δ on both sides
SD, ref and 88w, ref are added to the standards of the hydraulic position control devices 61 and 62 on both sides, respectively, and correct the rolling opening of the rolling mill 10 as the rolling opening operation amounts δsD and 88w on both sides, respectively.

By performing such control, the mlJ control device according to the present invention can control the rolling opening on both sides even in a rolling state where the amount of meandering increases rapidly and rolling cannot be continued in the conventional uncontrolled state. By automatically correcting it, it is possible to make the thickness deviation on both sides zero, so the amount of meandering can be made zero.

Note that the present invention is not limited to the above-described embodiments, and can be realized by a computer having equivalent functions within the scope of the invention.

〔Effect of the invention〕

As described above, according to the present invention, control is performed so that the thickness deviation calculated from the thickness of the drive side and the workpiece side of a metal rolling mill becomes a preset target value, so that the rolled material Meandering can be automatically prevented, improving productivity and quality.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the meandering of the material to be rolled. Figure (a) is a cross-sectional view of the rolling roller, and Figures (b), (c), and (d) are the thickness, advance rate, and backward rate of the material to be rolled, respectively. This is a graph showing. FIG. 2 is a block diagram showing an embodiment of a rolling mill control device according to the present invention. DESCRIPTION OF SYMBOLS 1... Rolling roll, 2... Rolled material, 10... Rolling machine, 31... Drive side delivery calculating device, 32...
Switch, 33... Drive side exit thickness storage device, 34...
・Subtractor, 41... Workpiece side protrusion thickness calculating device, 42...
・Switch, 43... Workpiece side thickness storage device, 44...
・Subtractor, 45...Subtractor, (capital)...Control calculation device, 51...Subtractor, 52・Spanning device, 53...P
ID controller, 54... Arithmetic unit, 55... Sign inverter, 61... Drive side hydraulic position control device, 62
...Work side hydraulic position control device f. Applicant's agent Kiyoshi Inomata Figure 1

Claims (1)

[Scope of Claims] 1. A control device for a rolling mill that rolls metal, which inputs the drive 9111# weight of the rolling mill and the drive side rolling opening of the rolling mill, and controls the drive side output using a gauge meter type. A drive side thickness calculation device that calculates the thickness; and a drive side thickness lock that is the drive side thickness at a stable arbitrary time (lock-on timing) after the rolled material is rolled in the rolling mill. a drive side thickness storage device that stores an ON value; and a first subtractor that calculates a difference between the drive side thickness lock-on value and the drive side thickness and outputs the result as a drive 9111 thickness deviation. and a workpiece side thickness calculation device that inputs the workpiece side load of the rolling mill and the workpiece side rolling opening of the rolling mill and calculates the edge workpiece side thickness using a gauge meter type (1); and the lock. a workpiece side thickness storage device that stores a workpiece side thickness lock-on value that is the workpiece side thickness at the on-timing; and a workpiece side thickness storage device that calculates the difference between the workpiece side thickness lock-on value and the workpiece side thickness; a second subtractor that outputs the result as a workpiece side thickness deviation; and a 30th subtractor that calculates the difference between the drive side thickness deviation and the workpiece side thickness deviation and outputs the result as a thickness deviation violet. A drive side reduction opening correction amount for inputting the thickness deviation amount and controlling the thickness deviation using a preset thickness deviation standard as a target value, and a drive side reduction opening correction amount. A control device for a rolling mill, comprising: a control calculation device that outputs a work-side rolling opening correction amount with the sign of the degree correction amount reversed;