JPS631131B2 - - Google Patents
Info
- Publication number
- JPS631131B2 JPS631131B2 JP56115988A JP11598881A JPS631131B2 JP S631131 B2 JPS631131 B2 JP S631131B2 JP 56115988 A JP56115988 A JP 56115988A JP 11598881 A JP11598881 A JP 11598881A JP S631131 B2 JPS631131 B2 JP S631131B2
- Authority
- JP
- Japan
- Prior art keywords
- rolling
- rolled
- rolling mill
- plate thickness
- thickness
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000005096 rolling process Methods 0.000 claims description 64
- 239000000463 material Substances 0.000 claims description 34
- 238000000034 method Methods 0.000 claims description 13
- 230000009467 reduction Effects 0.000 claims description 4
- 230000008859 change Effects 0.000 description 5
- 238000011144 upstream manufacturing Methods 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 238000005097 cold rolling Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000008901 benefit Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000004043 responsiveness Effects 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/16—Control of thickness, width, diameter or other transverse dimensions
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Control Of Metal Rolling (AREA)
Description
【発明の詳細な説明】
この発明は鋼板圧延における板厚制御方法に係
り、特に連続圧延機による薄板の精密圧延に好適
な板厚制御方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plate thickness control method in rolling a steel plate, and particularly to a plate thickness control method suitable for precision rolling of a thin plate using a continuous rolling mill.
従来の板厚制御方法としては、FF・AGCなど
のフイードフオワード的な制御方法や、
BISRA・AGCなどのフイードバツク的な制御方
法があり、後者においては応答性に限界があり、
被圧延材の板厚変動が急峻な場合などには精密圧
延が困難になるという問題があつた。また前者に
おいては、被圧延材の板厚変動に基づいてフイー
ドフオワード制御を行うため、被圧延材の硬度が
急激に変動した場合には精密圧延が困難になつ
た。 Conventional plate thickness control methods include feed forward control methods such as FF/AGC,
There are feedback control methods such as BISRA and AGC, but the latter has limited responsiveness.
There has been a problem in that precision rolling becomes difficult when the thickness of the material to be rolled varies sharply. Furthermore, in the former method, feedforward control is performed based on changes in the thickness of the material to be rolled, so precision rolling becomes difficult when the hardness of the material to be rolled changes rapidly.
また従来から連続圧延機において、上流圧延機
の圧延ロールの圧下位置や、圧延荷重から被圧延
材の塑性係数の変化を検出して、下流圧延機での
板厚変動を防止する技術も提案されている。 Furthermore, in continuous rolling mills, technology has been proposed that detects changes in the plasticity coefficient of the rolled material based on the rolling position of the rolling rolls in the upstream rolling mill and the rolling load to prevent plate thickness fluctuations in the downstream rolling mill. ing.
しかし、この技術では、塑性係数の変化を検出
する圧延機では通常の強圧下を行う圧延作業を行
つているため、塑性係数に変化がある場合はこの
変化が、当該圧延機の出側における板厚変動の原
因となり、また前記入側圧延機の入側板厚に変動
がある場合も当該圧延機の出側板厚に変動が残存
する。 However, with this technology, the rolling mill that detects changes in the plastic modulus performs rolling operations that perform normal heavy reduction, so if there is a change in the plastic modulus, this change is reflected in the plate at the exit side of the rolling mill. This causes a change in thickness, and even if there is a change in the thickness of the plate on the input side of the input side rolling mill, the variation remains in the thickness of the plate on the exit side of the rolling mill.
この場合、当該圧延機の出側板厚変動が相当に
大きいと、下流の圧延機で板厚を修正するための
制御を行つても正確な板厚の修正は困難である。 In this case, if the variation in plate thickness at the exit side of the rolling mill is considerably large, it is difficult to accurately correct the plate thickness even if control is performed to correct the plate thickness in the downstream rolling mill.
この発明はこのような従来の問題点を解消すべ
く創案されたもので、被圧延材の板厚や硬度が急
激に変化した場合にも精密な板厚制御を行い得る
板厚制御方法を提供することを目的とする。 This invention was devised to solve these conventional problems, and provides a thickness control method that allows precise thickness control even when the thickness or hardness of the rolled material changes rapidly. The purpose is to
この発明に係る板厚制御方法は、被圧延材をわ
ずかな圧下量で予圧延して圧下圧力の変動ΔPtを
求めるとともに、被圧延材の出側板厚変動ΔHを
厚さ計などによつて測定し、ΔtおよびΔHから被
圧延材の塑性係数Ｋを求め、ＫおよびΔHのデー
タを適宜板厚制御系に与え、ΔHの変動のみなら
ずＫをも考慮した板厚制御を行い、さらにΔHの
急激な変動についても精密な板厚制御を行うもの
である。 The plate thickness control method according to the present invention involves pre-rolling the material to be rolled with a small amount of reduction to determine the variation ΔPt in rolling pressure, and measuring the variation ΔH in the exit thickness of the material to be rolled using a thickness gauge or the like. Then, the plasticity coefficient K of the rolled material is determined from Δt and ΔH, the data of K and ΔH are given to the plate thickness control system as appropriate, and the plate thickness is controlled taking into account not only the variation of ΔH but also K. Precise plate thickness control is performed even when sudden changes occur.
次にこの発明に係る板厚制御方法の一実施例を
図面に基づいて説明すると、鋼板冷間圧延ライン
１においては、ペイオフリール２からテンシヨン
リール１３に向つて被圧延材３が送給され、その
中途において複数段の圧延機４によつて被圧延材
３の板厚が所期値になるように圧延を行つてい
る。圧延機群の前段には例えばデスケーリング装
置５が配置され、このデスケーリング装置５の前
段には、スケールを破砕するための予圧延機６が
配置されている。予圧延機６にはロードセル７が
設けられ、予圧延機６における圧下圧力Ptが測
定されている。予圧延機６の前段にはＸ線厚さ計
８が配置され、このＸ線厚さ計８によつて被圧延
材３の板厚Ｈが測定されている。 Next, an embodiment of the plate thickness control method according to the present invention will be described based on the drawings. In the steel plate cold rolling line 1, a material to be rolled 3 is fed from a payoff reel 2 toward a tension reel 13. In the middle of the process, rolling is performed by a multi-stage rolling mill 4 so that the thickness of the material to be rolled 3 becomes a desired value. For example, a descaling device 5 is arranged at the front stage of the rolling mill group, and a pre-rolling mill 6 for crushing scale is arranged at the front stage of the descaling device 5. The pre-rolling mill 6 is provided with a load cell 7, and the rolling pressure Pt in the pre-rolling mill 6 is measured. An X-ray thickness gauge 8 is disposed upstream of the pre-rolling mill 6, and the thickness H of the material to be rolled 3 is measured by this X-ray thickness gauge 8.
PtおよびＨのデータはCPU（計算機）９に入力
され、CPU９は、被圧延材３の一定長さ、例え
ば10〔ｍ〕ごとに、Pt，Ｈの変動、すなわち偏差
ΔPt，ΔHをそれぞれ算出する。 The data of Pt and H are input to the CPU (computer) 9, and the CPU 9 calculates the fluctuations of Pt and H, that is, the deviations ΔPt and ΔH, respectively, for every fixed length of the rolled material 3, for example, 10 [m]. .
ここで、
Ｍ；予圧延機６のミル定数
K0；被圧延材３の塑性係数の基準値
Ｋ；被圧延材３の実際の塑性係数
ΔH0；被圧延材の入側板厚変動
Δh1；被圧延材３の入側板厚変動による出側板
厚変動
Δh2；塑性係数がK0からＫに変化したことによ
る被圧延材３の出側板厚変動
とすると、
Δh1＝K0ΔH0／（K0＋Ｍ） …式(1)
Δh2＝ΔPt／（Ｋ＋Ｍ） …式(2)
であり、
ΔH＝Δh1＋Δh2 …式(3)
となるので、式(3)からＫの値を求めることができ
る。 Here, M; mill constant K 0 of the pre-rolling mill 6; reference value K of the plasticity coefficient of the material to be rolled 3; actual plasticity coefficient ΔH 0 of the material to be rolled 3; variation in plate thickness on the entrance side of the material to be rolled Δh 1 ; Variation in the thickness of the rolled material 3 on the exit side due to variation in the thickness at the entrance side Δh 2 ; Assuming the variation in the thickness of the rolled material 3 on the exit side due to the change in the plasticity coefficient from K 0 to K, Δh 1 = K 0 ΔH 0 / ( K 0 +M) ...Equation (1) Δh 2 = ΔPt/(K+M) ...Equation (2) and ΔH=Δh 1 +Δh 2 ...Equation (3) Therefore, calculate the value of K from Equation (3). be able to.
CPU９においては、ΔHおよびＫの値を、基準
値H0，K0を用いて次のように評価する。 The CPU 9 evaluates the values of ΔH and K using the reference values H 0 and K 0 as follows.
ΔH≦H0，Ｋ≦K0のとき
別段の対策を講じることなく、良好な板厚制御
を行い得る。 When ΔH≦H 0 and K≦K 0 , good plate thickness control can be performed without taking any special measures.
ΔH≦H0，Ｋ＞K0のとき
Ｋの値を特に考慮した圧延が必要であるとし
て、圧延機４の制御器１０に、Ｋの値を入力し、
さらに被圧延材３のそのＫの値を有する部分に、
マーキング装置１１によつてマーキングを施す。 When ΔH≦H 0 , K>K 0 It is necessary to perform rolling with special consideration of the value of K, so input the value of K into the controller 10 of the rolling mill 4,
Furthermore, in the part of the rolled material 3 having the value of K,
Marking is performed by a marking device 11.
ΔH＞H0，Ｋ≦K0のとき
ΔHの値を特に考慮した圧延が必要であるとし
て、制御器１０にΔHの値を入力し、さらに被圧
延材３のそのΔHの値を有する部分に、マーキン
グ装置１１によつてマーキングを施す。 When ΔH>H 0 , K≦K 0 It is necessary to perform rolling with special consideration of the value of ΔH, so input the value of ΔH into the controller 10, and then apply the , marking is performed by a marking device 11.
ΔH＞H0，Ｋ＞K0のとき
ΔHおよびＫの値を特に考慮した圧延が必要で
あるとして、制御器１０にΔHおよびＫの値を入
力し、さらに圧延材３のそのΔHおよびＫの値を
有する部分に、マーキング装置１１によつてマー
キングを施す。 When ΔH>H 0 , K>K 0 Since it is necessary to perform rolling with special consideration of the values of ΔH and K, input the values of ΔH and K into the controller 10, and further calculate the values of ΔH and K of the rolled material 3. A marking device 11 marks a portion having a value.
基準値H0およびK0は、材質等の条件により例
えば目標板厚Haに対して±3.5〜４％、また設定
塑性係数Kaに対して±３〜５％程度にする。 The reference values H 0 and K 0 are set, for example, to about ±3.5 to 4% with respect to the target plate thickness Ha, and about ±3 to 5% with respect to the set plasticity coefficient Ka, depending on conditions such as the material.
圧延機４の群の前段には、マーク検出器１２が
設けられ、マーキング装置１１によつて被圧延材
３に付与されたマークはこのマーク検出器１２に
よつて検出される。 A mark detector 12 is provided upstream of the group of rolling mills 4 , and marks applied to the rolled material 3 by the marking device 11 are detected by the mark detector 12 .
マーキング装置１１としては被圧延材３着磁す
る型式あるいは被圧延材３に穿孔する型式などが
採用され、ΔHまたはＫの急峻な変動を生じた部
分のみにマーキングを施し得るものである。さら
に前記マーキングに代えてΔHまたはＫの急峻な
変動を生じた部分をCPU９に記憶させ、この位
置が圧延機４の入側に到達する時刻をCPU９を
用い被圧延材３の速度に応じてトラツキングして
もよい。 As the marking device 11, a type that magnetizes the rolled material 3 or a type that perforates the rolled material 3 is adopted, and is capable of marking only the portion where a steep fluctuation in ΔH or K occurs. Furthermore, instead of the marking, the CPU 9 stores the part where the steep fluctuation of ΔH or K occurs, and the time when this position reaches the entrance side of the rolling mill 4 is tracked using the CPU 9 according to the speed of the rolled material 3. You may.
制御器１０は、CPU９から入力されたΔHよび
Ｋの値と、マーク検出器１２からの信号または
CPU９が記憶した位置のトラツキング信号に基
づいて、ΔHおよび／またはＫの値が特に大きい
部分については、これらの値を考慮した圧延を実
施する。 The controller 10 receives the values of ΔH and K input from the CPU 9 and the signal from the mark detector 12 or
Based on the position tracking signal stored by the CPU 9, rolling is performed in consideration of these values for parts where the values of ΔH and/or K are particularly large.
制御器１０は、BISRA・AGCなどの圧延荷
重、ロール開度、ミル定数、張力、出側板厚のフ
イードバツク等によつて板厚を自動制御するフイ
ードバツク制御系であり、ΔHまたはＫの値が小
さいときには、フイードバツク信号に基づいて精
密な板厚制御を行い得る。そしてΔHまたはＫに
値が大きいときには、あらかじめΔHまたはＫの
値が制御器１０に入力れることによつて、制御器
１０は急峻な圧延条件変化に追従し得るようにな
る。 The controller 10 is a feedback control system that automatically controls the plate thickness by feedback of rolling load, roll opening, mill constant, tension, exit side plate thickness, etc. such as BISRA/AGC, and the value of ΔH or K is small. In some cases, precise thickness control can be performed based on feedback signals. When the value of ΔH or K is large, the value of ΔH or K is input to the controller 10 in advance, so that the controller 10 can follow sudden changes in rolling conditions.
制御器１０においては前記ΔHおよびＫの値を
取り込み、例えば第一段圧延機では該当する部分
の板厚の修正量Δha1を、
Δha1＝f1（ΔH／Ha1，Ｋ／Ka1）・Ha1 …(4)
Ha1：第一段圧延機出側目標板厚、Ka1：第一
段圧延機設定塑性系数として与え、ロール開度お
よび被圧延材の張力を制御し、必要に応じて第二
段以降の圧延機も同様な制御を行う。 The controller 10 takes in the values of ΔH and K, and for example, in the first stage rolling mill, the correction amount Δha 1 of the plate thickness of the corresponding part is calculated as Δha 1 =f 1 (ΔH/Ha 1 , K/Ka 1 )・Ha 1 ...(4) Ha 1 : Target plate thickness at the exit side of the first stage rolling mill, Ka 1 : Given as the first stage rolling mill setting plasticity system, the roll opening degree and the tension of the rolled material are controlled, and the thickness is adjusted as necessary. Accordingly, the rolling mills in the second and subsequent stages also perform similar control.
従つて、いかなる条件においても常に精密な板
厚制御が可能となる。 Therefore, precise plate thickness control is always possible under any conditions.
前述のとおり、この発明に係る板厚制御方法
は、被圧延材を連続式圧延機の入側に設けた予圧
延機により、わずかな圧下量で予圧延して圧下圧
力の変動ΔPtを求めるとともに、被圧延材の板厚
変動ΔHを厚さ計などによつて測定し、ΔPtおよ
びΔHから被圧延材の塑性係数Ｋを求め、Ｋおよ
びΔHのデータを適宜板厚制御系に与え、ΔHの
変動のみならずＫをも考慮した板厚制御を行い、
さらにΔHの急峻な変動についても精密な板厚制
御を行うので、板厚精度を大幅に向上し得るとい
う優れた効果を有し、例えばブリキ用素材の圧延
において、オフゲージの割合を従来の1/3以下に
低下したという実績が得られている。 As mentioned above, the plate thickness control method according to the present invention involves pre-rolling a material to be rolled with a small amount of reduction using a pre-rolling machine installed on the entry side of a continuous rolling mill, and determining the variation ΔPt in rolling pressure. , measure the plate thickness variation ΔH of the rolled material using a thickness gauge, etc., find the plasticity coefficient K of the rolled material from ΔPt and ΔH, provide the data of K and ΔH to the plate thickness control system as appropriate, and calculate the value of ΔH. We perform plate thickness control that takes into account not only fluctuations but also K,
Furthermore, since precise plate thickness control is performed even with steep fluctuations in ΔH, it has the excellent effect of greatly improving plate thickness accuracy. We have a track record of reducing the number to 3 or less.
さらに、本発明ではデスケーリング装置の前段
に設けたスケール破砕のための予圧延機がある場
合はわずかな改造をすることにより利用できる利
点もある。 Furthermore, the present invention has the advantage that if there is a pre-rolling mill for scale crushing provided upstream of the descaling device, it can be used with slight modification.
なお、この発明は前記実施例に限定されるもの
ではなく、次のような変形が可能である。 It should be noted that the present invention is not limited to the above-mentioned embodiment, and the following modifications are possible.
予圧延機として、スケール破砕以外の用途の
予圧延機を用い、あるいは、Ｋ算出のための専
用の予圧延機を採用した構成。 A configuration in which a pre-rolling machine for purposes other than scale crushing is used as the pre-rolling machine, or a pre-rolling machine dedicated to K calculation is adopted.
圧延機全てについて、Ｋ，ΔHを考慮した圧
延を行わずに、第一段の圧延機についてのみこ
のような圧延を行う構成。実験によればこのよ
うな構成によつて充分高精度の圧延が可能であ
つた。 A configuration in which such rolling is performed only in the first stage rolling mill, without performing rolling in consideration of K and ΔH in all rolling mills. According to experiments, sufficiently high precision rolling was possible with such a configuration.
図面はこの発明に係る板厚制御方法の一実施例
を示すブロツク図である。
１…鋼板冷間圧延ライン、２…ペイオフリー
ル、３…被圧延材、４…圧延機、５…デスケーリ
ング装置、６…予圧延機、７…ロードセル、８…
Ｘ線厚さ計、９…CPU、１０…制御器、１１…
マーキング装置、１２…マーク検出器、１３…テ
ンシヨンリール。
The drawing is a block diagram showing an embodiment of the plate thickness control method according to the present invention. DESCRIPTION OF SYMBOLS 1... Steel plate cold rolling line, 2... Payoff reel, 3... Rolled material, 4... Rolling machine, 5... Descaling device, 6... Pre-rolling machine, 7... Load cell, 8...
X-ray thickness gauge, 9...CPU, 10...Controller, 11...
Marking device, 12... Mark detector, 13... Tension reel.
Claims (1)
な予圧延機に被圧延材を通過させて、このときの
圧下圧力の変動ΔPtを求めるとともに、被圧延材
の板厚の変動ΔHを求め、これらΔPtおよびΔH
から被圧延材の塑性係数Ｋを求め、ΔHまたはＫ
の値が所定値を越えた被圧延材の部分にマーキン
グを施すか、またはこの部分に対応する位置を記
憶し、かつ所定値を越えたΔHおよびＫの値を予
圧延機後方におかれた前記連続式圧延機に対し圧
延荷重、ミル定数等により板厚を制御する制御系
に入力し、この圧延機にて前記制御系に入力され
たΔHおよびＫの値と前記マーキング位置または
前記計算機の記憶位置の信号に基づいて被圧延材
を所期板厚に圧延する板厚制御方法。1. Pass the material to be rolled through a pre-rolling machine with a small amount of reduction installed on the entry side of the continuous rolling mill, and find the variation ΔPt in the rolling pressure at this time, and find the variation ΔH in the thickness of the material to be rolled. Find these ΔPt and ΔH
Find the plasticity coefficient K of the rolled material from ΔH or K
Mark the part of the material to be rolled where the value exceeds a predetermined value, or memorize the position corresponding to this part, and place the values of ΔH and K that exceed the pre-rolling mill behind the pre-rolling machine. The values of ΔH and K input to the control system of the continuous rolling mill and the marking position or the calculator are A plate thickness control method for rolling a material to be rolled to a desired thickness based on a signal from a stored position.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56115988A JPS5816721A (en) | 1981-07-24 | 1981-07-24 | Plate thickness controlling method in case of rolling steel plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56115988A JPS5816721A (en) | 1981-07-24 | 1981-07-24 | Plate thickness controlling method in case of rolling steel plate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5816721A JPS5816721A (en) | 1983-01-31 |
| JPS631131B2 true JPS631131B2 (en) | 1988-01-11 |
Family
ID=14676086
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56115988A Granted JPS5816721A (en) | 1981-07-24 | 1981-07-24 | Plate thickness controlling method in case of rolling steel plate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5816721A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2693498B2 (en) * | 1988-07-28 | 1997-12-24 | 石川島播磨重工業株式会社 | Continuous rolling equipment |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5148743A (en) * | 1974-10-24 | 1976-04-27 | Sumitomo Metal Ind | |
| JPS5426950A (en) * | 1977-08-03 | 1979-02-28 | Mitsubishi Electric Corp | Controlling method for sheet gauge |
| JPS5466363A (en) * | 1977-11-07 | 1979-05-28 | Ishikawajima Harima Heavy Ind Co Ltd | Control device for rolling |
-
1981
- 1981-07-24 JP JP56115988A patent/JPS5816721A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5148743A (en) * | 1974-10-24 | 1976-04-27 | Sumitomo Metal Ind | |
| JPS5426950A (en) * | 1977-08-03 | 1979-02-28 | Mitsubishi Electric Corp | Controlling method for sheet gauge |
| JPS5466363A (en) * | 1977-11-07 | 1979-05-28 | Ishikawajima Harima Heavy Ind Co Ltd | Control device for rolling |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5816721A (en) | 1983-01-31 |
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