JPS6142412A - Automatic plate thickness controlling device - Google Patents

Abstract

PURPOSE:To obtain fixed plate thickness controlling effect and to make the device very useful by estimating mill constant and plasticity coefficient of a steel plate during rolling and thereby changing gain of a screw down controlling system. CONSTITUTION:An automatic gain adjuster 10 calculates plasticity coefficient of steel plate Q, and mill constant M from input, entrance side plate thickness deviation DELTAH, exit side plate thickness deviation DELTAn, rolling load deviation DELTAP and roll gap deviation DELTAS and corrects alpha/m of mill constant M, and corrects gain of transfer function H1(S) of plasticity coefficient (q) of steel plate. Formerly, it was not possible to obtain sufficient plate thickness controlling function when the mill constant M and plasticity coefficient of steel plate Q fluctuate. However, this problem is eliminated by this way. Accordingly, the control gain of the plate thickness controlling device can be maintained at optimum operating condition at all times.

Description

【発明の詳細な説明】 発明の技術分野 本発明は、熱間又は冷間圧延工程の、入側及び出側板厚
針を持った圧延機に用いるに好適な自動板厚制御装置に
関する。DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an automatic plate thickness control device suitable for use in a rolling mill having entry and exit thickness needles in a hot or cold rolling process.

従来技術と問題点 一般に熱間圧延工程ではその最終段仕上圧延機で製品寸
法の板厚が得られるようにする圧延が行なわれ、又冷間
圧延工程でもその最終段仕上圧延機により製品寸法の板
厚が得られるまで圧延が行なわれる。また熱間圧延工程
では、加熱炉内での温度偏差（スキッドマークと言う）
が存在するので、圧下設定のみによる圧延では板厚変動
を生じる。Prior Art and Problems In general, in the hot rolling process, rolling is carried out to obtain the thickness of the product in the final stage finishing mill, and in the cold rolling process, the finishing mill in the final stage is used to achieve the product dimensions. Rolling is carried out until the plate thickness is obtained. In addition, during the hot rolling process, temperature deviations in the heating furnace (called skid marks)
Because of this, rolling using only the reduction settings causes variations in plate thickness.

そのため出側板厚変動をなくすべく、ＡＧＣ制御装置が
設置されている。又冷間圧延工程では、熱間圧延工程を
経たコイルが更に圧延されるが、同様にトップ、ボトム
、スキッドマークにおける出側板厚変動をなくすために
、ＡＧＣ制御装置が設置されている。Therefore, an AGC control device is installed to eliminate variations in the thickness of the outlet side. In the cold rolling process, the coil that has undergone the hot rolling process is further rolled, and an AGC control device is installed to similarly eliminate variations in the exit side thickness at the top, bottom, and skid marks.

この人ａｃ制御装置では、ロードセル、ロールギャップ
検出器などの各検出端からの信号、およびミル定数Ｍ、
ｗＩ板塑性係数Ｑを用いて圧延機内の板厚を演算し、目
標板厚となる様にロールギャップを調整するという制御
が行なわれる。しかし、ミル定数は圧延ロール摩擦係数
、ロール速度、ロール軸受油膜変化などにより変化し、
又鋼板塑性係数（変形抵抗）は鋼板温度、材質、入側張
力。In this human AC control device, signals from each detection end such as a load cell and a roll gap detector, and a mill constant M,
Control is performed in which the plate thickness inside the rolling mill is calculated using the wI plate plasticity coefficient Q, and the roll gap is adjusted so that the target plate thickness is achieved. However, the mill constant changes depending on factors such as the rolling roll friction coefficient, roll speed, and changes in the roll bearing oil film.
Also, the steel plate plasticity coefficient (deformation resistance) is determined by the steel plate temperature, material, and entry tension.

出側張力などにより変化する。It changes depending on the exit tension, etc.

近年省エネルギー化が推進され、低温加熱圧延方法が実
用化されているが、この圧延方法は鋼板板厚変動を増大
させる傾向にある。一方、品質向上、歩留り向上の観点
から鋼板板厚変動をなくすために種々の設備が設置され
ているが、上記に述べた様に圧延加工時のミル定数及び
鋼板塑性係数を各鋼板毎に事前に推定する事は困難であ
る。特に鋼板の先端部及び後端部は、鋼板中央部に比べ
て温度が低く、鋼板塑性係数が異なるため板厚制御効果
が十分に得られない。In recent years, energy saving has been promoted and a low-temperature heating rolling method has been put into practical use, but this rolling method tends to increase variation in steel sheet thickness. On the other hand, various equipment has been installed to eliminate variations in steel plate thickness from the viewpoint of improving quality and yield. It is difficult to estimate. In particular, the temperature at the front end and the rear end of the steel plate is lower than that at the center of the steel plate, and the steel plate plasticity coefficients are different, so that a sufficient plate thickness control effect cannot be obtained.

従来、ミル定数の変化及び鋼板塑性係数の変化によるＡ
ＧＣ制御効果の低減を補償するために、鋼板寸法及び鋼
種毎に、ＡＧＣ制御系の動作を変化させるパラメーター
であるＡＧＣゲイン及び正帰還率を変更していた。しか
し、ＡＧＣゲイン及び正帰還率はプロセス計算機で数学
モデルに基づき計算されているが、このモデルは精度上
限界を有し、特に鋼板の先端部、後端部におけるモデル
は実鋼板の現象と大きく異なっている。Conventionally, A due to changes in mill constant and steel plate plasticity coefficient
In order to compensate for the reduction in the GC control effect, the AGC gain and positive feedback rate, which are parameters that change the operation of the AGC control system, are changed for each steel sheet size and steel type. However, the AGC gain and positive feedback rate are calculated using a process computer based on a mathematical model, but this model has an accuracy limit, and in particular, the model at the leading and trailing ends of the steel plate is significantly different from the phenomena observed in the actual steel plate. It's different.

発明の目的 本発明は前記欠点を解消するべくなされたもので、既設
圧延機に用いるに好適な適応ＡＧＣ制御装置を提供する
事を目的とする。OBJECTS OF THE INVENTION The present invention was made to eliminate the above-mentioned drawbacks, and an object of the present invention is to provide an adaptive AGC control device suitable for use in an existing rolling mill.

発明の構成 本発明は、自動圧下制御機構を備えそして入側板厚、出
側板厚、圧延荷重、及びロール開度各検出器を有する圧
延機の自動板厚制御装置において、前記各検出器が出力
する入側板厚、出側板厚、圧延荷重及びロールギャップ
各信号を圧延中に取込み、これらの信号よりミル定数及
び鋼板塑性係数を算出し、設定ミル定数及び設定鋼板塑
性係数との差を求め、該差により圧下制御系の利得を修
正する自動利得調整器を設けたことを特徴とするが、次
に図面を参照しながらこれを説明する。Structure of the Invention The present invention provides an automatic plate thickness control device for a rolling mill, which is equipped with an automatic rolling down control mechanism and has detectors for input plate thickness, outlet plate thickness, rolling load, and roll opening, in which each of the detectors outputs an output. The input side plate thickness, exit side plate thickness, rolling load, and roll gap signals are taken in during rolling, the mill constant and steel plate plasticity coefficient are calculated from these signals, and the difference between the set mill constant and the set steel plate plasticity coefficient is determined. The present invention is characterized by the provision of an automatic gain adjuster that corrects the gain of the reduction control system based on the difference, which will be explained next with reference to the drawings.

発明の実施例 通常、製品寸法まで圧延加工を行なう仕上圧延機には入
側板厚針、出側板厚耐、ロードセル、及びロールギャッ
プ検出器が設定されており、これらの出力信号に基づき
ＡＧＣ制御装置は製品寸法への鋼板板厚制御を行なって
いる。第１図にＡＧＣ制御装置のブロック図を示す。図
中のΔＨは入側板厚偏差、Δｈは出側板厚偏差、ΔＰは
圧延荷重偏差、ΔＳはロールギャップ偏差、Ｍはミル定
数、ｍはプロセス計算機より設定されたミル定数、そし
てＱは鋼板塑性係数である。Ｑ／　（Ｍ＋Ｑ）などは圧
延機のモデル式であって、このＡＧＣ系では次の制御を
行なう。即ち、入側板厚偏差ΔＨがあるとそれにミルモ
デル式（詳しはΔｈに対するΔＨについてのミルモデル
式、以下これに準する）を乗じたΔＨ−Ｑ／　（Ｍ＋Ｑ
）なる出側板厚偏差Δｈを生じる。そこでロールギャッ
プを変えて即ちΔＳを発生させ、これにミルモデル式を
乗じて得られるΔＳ−Ｍ／　（Ｍ＋Ｑ）なる出側板厚偏
差を生じさせ、これで上記Δｈを０にする。Ｈ２（Ｓ）
は圧下モータ又は油圧サーボの伝達関数、Ｈｌ（Ｓ）は
ＡＧＣ装置の増幅器の伝達関数であり、これらの圧下制
御系が上記ΔＳを発生する。入側板厚偏差ΔＨがあり、
またロールギャップ偏差ΔＳがあると、これらの和にミ
ルモデル式ＭＱ／（Ｍ−１−Ｑ）を乗じたものが圧延荷
重偏差ΔＰになり、それをミル定数で割ったものが修正
すべきロールギャップである。制御装置は計算機から与
えられたミル定数ｍでΔＰを割り、それに補正係数αを
乗じてロールギャップ制御の目標値とする。この目標値
で、そして実際のロールギャップ修正量ΔＳを負帰還し
ながら、圧下制御系Ｈ１（Ｓ）、Ｈ２（Ｓ）は上記ΔＳ
を発生する。Embodiment of the Invention Normally, a finishing rolling mill that performs rolling processing to product dimensions is equipped with an entry side thickness needle, an exit side thickness gauge, a load cell, and a roll gap detector, and an AGC control device is activated based on the output signals of these. controls the steel plate thickness to match the product dimensions. FIG. 1 shows a block diagram of the AGC control device. In the figure, ΔH is the entrance side plate thickness deviation, Δh is the exit side plate thickness deviation, ΔP is the rolling load deviation, ΔS is the roll gap deviation, M is the mill constant, m is the mill constant set by the process calculator, and Q is the steel plate plasticity. It is a coefficient. Q/(M+Q) is a model equation of a rolling mill, and this AGC system performs the following control. In other words, when there is an entry side thickness deviation ΔH, it is multiplied by the Mill model formula (for details, the Mill model formula for ΔH against Δh, hereinafter referred to) is calculated as ΔH−Q/ (M+Q
), the exit side plate thickness deviation Δh is produced. Therefore, by changing the roll gap, that is, ΔS is generated, and by multiplying this by the Mill model equation, an exit plate thickness deviation of ΔS−M/(M+Q) is generated, thereby setting the above Δh to 0. H2(S)
is the transfer function of the reduction motor or hydraulic servo, and Hl(S) is the transfer function of the amplifier of the AGC device, and these reduction control systems generate the above-mentioned ΔS. There is an entry side plate thickness deviation ΔH,
Also, if there is a roll gap deviation ΔS, the sum of these times multiplied by the mill model formula MQ/(M-1-Q) becomes the rolling load deviation ΔP, which is divided by the mill constant to determine the roll to be corrected. It's a gap. The control device divides ΔP by the mill constant m given by the computer, multiplies it by a correction coefficient α, and sets the result as a target value for roll gap control. At this target value and while negative feedback of the actual roll gap correction amount ΔS, the reduction control systems H1(S) and H2(S) are adjusted to the above ΔS.
occurs.

ところで圧延理論よりミル定数Ｍにはｆｌ１式の関係式
が成立する。By the way, according to the rolling theory, the relational expression fl1 is established for the mill constant M.

Ｍ＝ｆＭ　（ｐ、ｖ、　　ε、　Δ５ｏｉｌ　、　−）
　−（１１μ＝ロール摩擦係数 Ｖ：ロール速度 ε：先進率 Δ５ｏｉｌ　：軸受油膜変化 又鋼板塑性係数Ｑには（２）式の関係式が成立する。M=fM (p, v, ε, Δ5oil, −)
-(11μ=roll friction coefficient V: roll speed ε: advance rate Δ5oil: bearing oil film change and steel plate plasticity coefficient Q, the relational expression (2) holds true.

Ｑ＝　ｆ（、（Ｔｐ、　Ｔｂ、　Ｔｆ、　Ｃ，・・・・
・・）　　・・・・・・（２）Ｔｐ：鋼板温度 Ｔｂ：後方張力 Ｔｆ：前方張力 Ｃ：含有炭素量 （１１，（２１式に示されるようにミル定数Ｍ１鋼板塑
性係数Ｑは速度、摩擦係数、入側張力、出側張力などで
変動するものであり、この変動に対してプロセス計算機
から各８Ｈ板毎に、正確なｍ定数及び鋼板塑性係数Ｑを
設定する事は困難である。Q= f(, (Tp, Tb, Tf, C,...
...) ...(2) Tp: Steel plate temperature Tb: Back tension Tf: Front tension C: Carbon content (11, (As shown in equation 21, the mill constant M1 steel plate plasticity coefficient Q is the speed, It varies depending on the friction coefficient, inlet tension, outlet tension, etc., and it is difficult to set an accurate m constant and steel plate plasticity coefficient Q for each 8H plate using a process computer in response to these variations.

そこで本発明ではＡＧＣ装置への入力信号からミル定数
Ｍ及び鋼板塑性係数Ｑを推定し、この推定値Ｍ、Ｑと制
御装置に設定されたＭ、　Ｑとの差ΔＭ、ΔＱを求め、
その差により圧下制御系の伝達関数Ｈ＋（Ｓ）の利得を
変更し、出側板厚偏差を一層正確に零にしようとするも
のである。Therefore, in the present invention, the mill constant M and the steel plate plasticity coefficient Q are estimated from the input signal to the AGC device, and the differences ΔM and ΔQ between these estimated values M and Q and M and Q set in the control device are determined.
The purpose is to change the gain of the transfer function H+(S) of the reduction control system based on the difference, and to more accurately reduce the exit side plate thickness deviation to zero.

ＡＧＣ装置への入力信号からＭ、Ｑを推定することは可
能であり、特開昭５８−１３２３０９　すどにも開示さ
れている。即ち入側板厚偏差ΔＨから出側板厚偏差Δｈ
を差引いたも°のが圧延機における正味の板厚偏差であ
り、これに鋼板塑性係数Ｑを乗じたものが圧延荷重変化
であるから下記（３）式が成立し、またゲージメータの
式ｈ＝ｓ＋Ｐ／Ｍから明らかなようにミル定数Ｍには下
記（４）式が成立する。It is possible to estimate M and Q from the input signal to the AGC device, and this is also disclosed in Japanese Patent Laid-Open No. 58-132309. In other words, the inlet side plate thickness deviation ΔH to the outlet side plate thickness deviation Δh
is the net plate thickness deviation in the rolling mill, and multiplying this by the steel plate plasticity coefficient Q is the rolling load change, so the following formula (3) holds true, and the gauge meter formula h As is clear from =s+P/M, the following formula (4) holds true for the Mill constant M.

そこでＡＧＣ装置に入力される、入側板厚信号Δ■］、
出側板厚信号Δｈ、ロードセル信号ΔＰ及びロールギャ
ップ偏差信号ΔＳを用いて（３１，（４１式を計算すれ
ば、鋼板・圧延加工時のミル定数Ｍ、鋼板塑性係数Ｑが
求まる。こ〜でハソｔ（”）は推定値を示す。制御装置
に計算機から与えられるミル定数ｍはＭに一致させる事
が必要なので、ミル定数推定値Ｍの変動に比例してｍを
変更する。There, the input side plate thickness signal Δ■] is input to the AGC device.
Using the exit plate thickness signal Δh, the load cell signal ΔP, and the roll gap deviation signal ΔS, the mill constant M and the steel plate plasticity coefficient Q during rolling of the steel plate can be found by calculating equations 31 and 41. t('') indicates an estimated value. Since it is necessary for the Mill constant m given to the control device by the computer to match M, m is changed in proportion to fluctuations in the estimated Mill constant value M.

また鋼板塑性係数Ｑの変動は制御系のループゲインを変
化させるから、ＡＧＣ装置の増幅器の伝達関数■１１　
（Ｓ）のゲインをミル定数推定価Ｍの変動に伴ない変化
させる。In addition, since fluctuations in the steel plate plasticity coefficient Q change the loop gain of the control system, the transfer function of the AGC device amplifier ■11
The gain of (S) is changed in accordance with the fluctuation of the Mill constant estimation value M.

本発明のＡＧＣ装置の構成を第２図に示す。破線枠で囲
った自動利得調整器１０が本発明で付加したものであり
、外部は第１図に示したＡＧＣ装Δｈ、ΔＰ、ΔＳから
上記Ｑ、　Ｍを算出し、Ｍで７７ｍを、ＱでＨＩ　（Ｓ
）のゲインを修正する。FIG. 2 shows the configuration of the AGC device of the present invention. The automatic gain adjuster 10 surrounded by a broken line frame is added in the present invention, and the external AGC device shown in FIG. 1 calculates the above Q and M from Δh, ΔP, and ΔS. De HI (S
).

この様にすれば、従来ミル定数及び鋼板塑性係数が変動
するとＡＧＣ装置の十分な板厚制御機能が得られなかっ
たが、この点を解消し、ミル定数及び鋼板塑性係数の変
動に対して、ＡＧＣ装置の制御ゲインを常に最適動作状
態に維持することができる。In this way, if the mill constant and steel plate plasticity coefficient fluctuate, the AGC device could not obtain sufficient plate thickness control function, but this problem is solved and the mill constant and steel plate plasticity coefficient change The control gain of the AGC device can always be maintained in an optimal operating state.

発明の詳細 な説明したように本発明では圧延中にミル定数Ｍ及び鋼
板塑性係数を推定し、これにより圧下制御系の利得を変
えるようにしたのでスキッドマークによる鋼板塑性係数
の変動、鋼板先端部及び後端部の鋼板塑性係数の変動に
対し、一定の板厚制御効果が得られ、甚だ有用である。As described in detail, in the present invention, the mill constant M and the steel plate plasticity coefficient are estimated during rolling, and the gain of the rolling control system is changed accordingly, so that fluctuations in the steel plate plasticity coefficient due to skid marks and the steel plate tip end are avoided. A constant plate thickness control effect can be obtained with respect to variations in the steel plate plasticity coefficient at the rear end portion, and is extremely useful.

【図面の簡単な説明】[Brief explanation of drawings]

第１図はＡＧＣ系の構成を伝達関数で示すプロツク図、
第２図は本発明の実施例を示すブロック図である。 図面で、１０は自動利得調整器である。Figure 1 is a block diagram showing the configuration of the AGC system using a transfer function.
FIG. 2 is a block diagram showing an embodiment of the present invention. In the drawing, 10 is an automatic gain adjuster.

Claims (1)

【特許請求の範囲】 自動圧下制御機構を備えそして入側板厚、出側板厚、圧
延荷重、及びロール開度各検出器を有する圧延機の自動
板厚制御装置において、 前記各検出器が出力する入側板厚、出側板厚、圧延荷重
及びロールギャップ各信号を圧延中に取込み、これらの
信号よりミル定数及び鋼板塑性係数を算出し、設定ミル
定数及び設定綱板塑性係数との差を求め、該差により圧
下制御系の利得を修正する自動利得調整器を設けたこと
を特徴とする自動板厚制御装置。[Scope of Claims] An automatic plate thickness control device for a rolling mill, which is equipped with an automatic rolling down control mechanism and has detectors for input plate thickness, outlet plate thickness, rolling load, and roll opening, each of which has outputs from each of the detectors. Input side plate thickness, exit side plate thickness, rolling load and roll gap signals during rolling, calculate the mill constant and steel plate plasticity coefficient from these signals, find the difference from the set mill constant and set steel plate plasticity coefficient, An automatic plate thickness control device comprising an automatic gain adjuster that corrects the gain of the rolling control system based on the difference.