JPH0890034A - Method for controlling thickness in hot tandem rolling mill - Google Patents

Method for controlling thickness in hot tandem rolling mill

Info

Publication number
JPH0890034A
JPH0890034A JP6219194A JP21919494A JPH0890034A JP H0890034 A JPH0890034 A JP H0890034A JP 6219194 A JP6219194 A JP 6219194A JP 21919494 A JP21919494 A JP 21919494A JP H0890034 A JPH0890034 A JP H0890034A
Authority
JP
Japan
Prior art keywords
tension
stands
control
value
rolling
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.)
Withdrawn
Application number
JP6219194A
Other languages
Japanese (ja)
Inventor
Toshiaki Ueno
俊昭 上之
Yutaka Nakayama
豊 中山
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Corp
Original Assignee
Nippon Steel Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nippon Steel Corp filed Critical Nippon Steel Corp
Priority to JP6219194A priority Critical patent/JPH0890034A/en
Publication of JPH0890034A publication Critical patent/JPH0890034A/en
Withdrawn legal-status Critical Current

Links

Landscapes

  • Control Of Metal Rolling (AREA)

Abstract

PURPOSE: To improve thickness precision, in controlling the thickness of a rolling stock in a hot tandem rolling mill, by suppressing a steep tension change at the tip end of a metallic material. CONSTITUTION: In a thickness control method in a hot tandem rolling mill that is provided with plural rolling stands 1 and plural devices 3 for controlling tension between stands; after a rolling stock 4 passes between arbitrary stands 1, a tension control 24 is performed using as a target tension 23 the actual tension value at the point of time when a corresponding device 3 for controlling tension between stands starts controlling; after a prescribed time is elapsed, the target tension 23 between the stands is changed so that it is gradually changed into a value different from the target; and a change at the tip end of the rolling stock is suppressed which is due to a change in tension at the tip end of the rolling stock.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、複数個の圧延スタンド
とスタンド間張力制御装置を有する熱間タンデム圧延機
における板厚制御方法に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strip thickness control method in a hot tandem rolling mill having a plurality of rolling stands and a tension control device between stands.

【0002】[0002]

【従来の技術】熱間タンデム圧延機における板厚制御方
法は、圧延材料が各スタンドに噛み込む前に、圧下位置
を初期設定する板厚セットアップ制御と、各スタンドに
噛み込んだ後に圧下位置を変える板厚ダイナミック制御
とに大別される(日本鉄鋼協会「板圧延の理論と実際」
p289,p295)。
2. Description of the Related Art A plate thickness control method for a hot tandem rolling mill is a plate thickness setup control for initially setting a rolling position before the rolled material is bitten into each stand, and a rolling position after biting into each stand. It is roughly divided into changing plate thickness dynamic control (The Iron and Steel Institute of Japan "Theory and practice of plate rolling"
p289, p295).

【0003】板厚ダイナミック制御はセットアップ制御
と比べ、セットアップ制御誤差を圧延機の途中から修正
できる点において優れている。
The plate thickness dynamic control is superior to the setup control in that the setup control error can be corrected from the middle of the rolling mill.

【0004】ところが、板厚ダイナミック制御の場合、
制御の開始タイミングを早めすぎるとスタンド間の張力
及びルーパ角度が整定しない時に圧下位置変更によるス
タンド間速度外乱が加わり、スタンド間張力・ルーパ角
度が不安定になりミスロールを誘発し易い。そのため
に、通常は圧延材料の先端部が当該スタンドを通過して
板厚ダイナミック制御を開始する間を数秒に設定してい
る。
However, in the case of plate thickness dynamic control,
If the control start timing is too early, when the tension between the stands and the looper angle are not settled, speed disturbance between the stands due to the change of the rolling position is added, and the tension / looper angle between the stands becomes unstable and it is easy to induce a misroll. Therefore, the interval between the leading end of the rolled material passing through the stand and starting the thickness dynamic control is usually set to several seconds.

【0005】図3は熱間タンデム圧延機のプロセスイメ
ージを示すものである。図中、1は圧延スタンド、2は
出側板厚計、3は張力制御装置(ルーパ)、4は圧延材
料、5は通板方向、6は板厚制御装置(圧下装置)を示
している。
FIG. 3 shows a process image of the hot tandem rolling mill. In the figure, 1 is a rolling stand, 2 is a delivery side plate thickness gauge, 3 is a tension control device (looper), 4 is a rolling material, 5 is a sheet passing direction, and 6 is a plate thickness control device (rolling down device).

【0006】図4は従来における制御フロー説明図であ
る。ステップ11において、iスタンドのメタルインを
検出すると、ステップ12,13で、メタルインT1
経過後にi−1〜iスタンド間の張力制御を開始する。
そして、ステップ14,15で、メタルインT2 (>T
1 )経過後に、i−1スタンド、板厚ダイナミック制御
を開始する。
FIG. 4 is an explanatory diagram of a conventional control flow. When the metal-in of the i-stand is detected in step 11, the tension control between i-1 to i-stand is started in steps 12 and 13 after the metal-in T 1 second has elapsed.
Then, in steps 14 and 15, metal-in T 2 (> T
1 ) After the elapse, the i-1 stand and the plate thickness dynamic control are started.

【0007】この圧延材料先端部の板厚ダイナミック制
御未使用区間において、スタンド間張力制御が開始する
時点で実績張力値と目標張力値に差が生じている時(通
常、先端部通板性確保のために実績張力値は目標張力値
より高目である。特に、通板性の困難な後段2〜3スタ
ンド間張力についてあてはまる。)に張力制御を開始す
ることによって、実績張力値が目標張力値へと急峻に変
化し、(1)式の関係から先端部板厚精度が変動しオフ
ゲージに到る場合があるという問題があった。
In the unused section of the thickness dynamic control of the front end of the rolled material, when a difference between the actual tension value and the target tension value occurs at the time when the inter-stand tension control starts (usually, the front end threadability is ensured). Therefore, the actual tension value is higher than the target tension value. In particular, the actual tension value is applied to the tension between the second and third stands, which is difficult to pass through. However, there is a problem in that the tip thickness accuracy may change due to the relationship of the equation (1) and may reach an off gauge.

【0008】[0008]

【数1】 ここで、h:スタンド出側板厚 S:ワークロール間隙 tb :後方張力応力 tf :前方張力応力 H:スタンド入側板厚 μ:ワークロールと圧延材料の間の摩擦係数 k:圧延材料の降伏応力を表す定数[Equation 1] Here, h: stand delivery side thickness S: work roll gap t b: backward tension stress t f: forward tension stresses H: stand entry side thickness mu: coefficient of friction between the work rolls and the rolling material k: yield of the rolled material Constant that expresses stress

【0009】図5はその動作を説明するための図であ
り、図5(a)に示すように、たとえば6〜7スタンド
間張力が、7スタンドメタルイン後T1 経過後に目標張
力値に対して実績値が大きければ、同図(b)に示すよ
うに6〜7スタンド間張力制御がオンになる。さらに同
図(d)に示すように7スタンドメタルイン後T2 経過
後に6号スタンドの板厚制御モードがオンになり、
(c)に示すようにワークロールギャップが修正され
る。これにより、同図(e)に示すように出側板厚は、
張力制御モード、板厚制御モード切替時に目標値に対し
て変動し、オフゲージに至っている。
FIG. 5 is a diagram for explaining the operation. As shown in FIG. 5 (a), for example, the tension between 6 and 7 stands is relative to the target tension value after T 1 has elapsed after 7 stand metal-in. If the actual value is large, the tension control between 6 and 7 stands is turned on as shown in FIG. Further, as shown in FIG. 6 (d), the plate thickness control mode of the No. 6 stand is turned on after a lapse of T 2 after 7 stand metal in
The work roll gap is corrected as shown in (c). As a result, as shown in (e) of FIG.
When the tension control mode and the plate thickness control mode are switched, it fluctuates with respect to the target value and reaches the off gauge.

【0010】かかる問題に対して、先行技術として、タ
ンデム圧延機出側の板厚計に材料先端部が到達した際
に、板厚偏差が小さい場合にスタンド間張力を保持し張
力の変動による板厚変動を抑制し、オフゲージを防ぐ手
法が提案されている。
In order to solve such a problem, as a prior art, when the tip of the material reaches the strip thickness gauge on the delivery side of the tandem rolling mill, when the strip thickness deviation is small, the tension between the stands is held and the strip is caused by the variation of the tension. Techniques have been proposed for suppressing thickness variation and preventing off gauge.

【0011】[0011]

【発明が解決しようとする課題】しかしながら、上記手
法では板厚計に材料が到達した後にスタンド間張力、特
に、材料先端部の張力変動が特に顕著であるタンデム圧
延機後段2〜3スタンド間張力を保持させるために、材
料先端部から約30m程度は、板厚変動を防止できない
という欠点があった。
However, in the above method, the tension between the stands after the material reaches the plate thickness gauge, particularly the tension between the two or three stands after the tandem rolling mill, in which the fluctuation of the tension at the tip of the material is particularly remarkable. In order to retain the above, there is a drawback in that it is not possible to prevent the plate thickness variation about 30 m from the tip of the material.

【0012】本発明が解決すべき課題は、熱間タンデム
圧延機における圧延材の板厚制御において、メタル先端
部の急峻な張力変動を抑制して、板厚精度を向上させる
ことにある。
[0012] The problem to be solved by the present invention is to suppress the steep tension fluctuation of the metal tip in the plate thickness control of the rolled material in the hot tandem rolling mill to improve the plate thickness accuracy.

【0013】[0013]

【課題を解決するための手段】前記課題を解決するた
め、本発明は、複数個の圧延スタンド及び複数個のスタ
ンド間張力制御装置を有する熱間タンデム圧延機におけ
る板厚制御方法において、任意のスタンド間を圧延材料
が通過した後、該当するスタンド間張力制御装置が制御
開始する時点の張力実績値を目標張力値として張力制御
を行い、所定の時間後、当該スタンド間の目標張力値を
前記目標値とは別の値に次第に変化するように変更し圧
延材料先端部張力変動による圧延材料先端部変動を抑制
するものである。
In order to solve the above problems, the present invention provides an optional plate thickness control method in a hot tandem rolling mill having a plurality of rolling stands and a plurality of inter-stand tension control devices. After the rolled material passes between the stands, the tension control is performed with the actual tension value at the time when the corresponding inter-stand tension control device starts the control as the target tension value, and after a predetermined time, the target tension value between the stands is The value is changed so that it gradually changes to a value different from the target value, and fluctuations in the rolling material tip portion due to fluctuations in the rolling material tip portion tension are suppressed.

【0014】[0014]

【作用】上記(1)式により、上述の板厚ダイナミック
制御未制御区間における板厚変動を除去するためには、
張力の変化を無くす必要がある。本発明では、メタルイ
ン後の張力実績値を制御開始する時点の目標値とし、所
定の時間後に目標値を別の目標値に漸近させることで、
板厚変動の少ない板が得られる。
In order to eliminate the plate thickness fluctuation in the above-mentioned plate thickness dynamic control uncontrolled section by the above formula (1),
It is necessary to eliminate the change in tension. In the present invention, the actual tension value after metal-in is set as the target value at the time of starting control, and the target value is gradually approached to another target value after a predetermined time,
A plate with less variation in plate thickness can be obtained.

【0015】張力実績値を張力目標値とすることで、そ
れ以後の張力変動((1)式におけるΔtb ,Δtf
が0となり、図2(c)に示す、材料先端からT2 秒後
(例えば1.5秒)までは、板厚制御が開始せずΔS=
0、また、スキッド等による温度変動についても最先端
部であるために発生しないため、ΔH,Δμ,Δkもほ
ぼ0である。そこで(1)式よりΔh≒0となり、図2
のT1 秒(例えば1秒)後からT2 秒後に到るまでは、
図2(e)に示すように出側板厚は変動しない。但し、
目標板厚との僅かな差Δh1 (図2(e)参照)は存在
するが、その差はほとんどオフゲージ範囲内である。
By using the actual tension value as the target tension value, the subsequent tension fluctuations (Δt b , Δt f in the equation (1)).
Becomes 0, and the sheet thickness control does not start until T 2 seconds (for example, 1.5 seconds) from the material front end, as shown in FIG. 2C, and ΔS =
Also, since temperature fluctuations due to skids and the like do not occur at the leading edge, ΔH, Δμ, and Δk are almost 0. Therefore, from equation (1), Δh ≈ 0, and
From T 1 seconds (for example, 1 second) to T 2 seconds later,
As shown in FIG. 2 (e), the outlet plate thickness does not change. However,
Although there is a slight difference Δh 1 (see FIG. 2E) from the target plate thickness, the difference is almost within the off gauge range.

【0016】[0016]

【実施例】以下、本発明を図面により詳細に説明する。
図1は本発明の板厚制御方法の制御フロー、図2はその
制御動作を示すタイムチャートである。
The present invention will be described in detail below with reference to the drawings.
FIG. 1 is a control flow of the plate thickness control method of the present invention, and FIG. 2 is a time chart showing the control operation.

【0017】図1において、ステップ21でiスタンド
のメタルインを検出すると、ステップ22,23,24
で、当該スタンド間を材料が通過してT1 秒(例えば1
秒)経過後にi−1〜iスタンド間の張力制御を開始す
る(図2(b)参照)。そのときの張力実績値を記憶
し、この記憶値を張力目標値とする。ついで、ステップ
27,28で、メタルインT2 (>T1 )(例えば1.
5秒)経過後に、i−1スタンドの板厚ダイナミック制
御を開始する(図2(d)参照)。これにより、i−1
スタンドのワークロールギャップが修正される(図2
(c)参照)。さらに、ステップ25,26で、メタル
インT3 (>T2 )(例えば4秒)経過後に張力目標値
を別の目標値に変更する(図2(a)参照)。この変更
は、ステップ的ではなく、ランプ関数、指数関数などを
用いて漸近させ、材料中間部の通板に最適な張力値に復
帰させる(図2(a)参照)。この動作により、先端部
の急峻な張力変動を防止することができ、板厚変動の抑
制を図ることができる(図2(e)参照)。T3 後の張
力目標値は、材料尾端部が通板する際にハネたりしてワ
ークロール疵を発生しないための張力(通常、材料先端
部通板張力より小さい)とする。
In FIG. 1, when the metal-in of the i stand is detected in step 21, steps 22, 23, 24 are performed.
Then, when the material passes between the stands, T 1 seconds (for example, 1
After the elapse of (seconds), tension control between the i-1 to i stands is started (see FIG. 2B). The actual tension value at that time is stored, and this stored value is used as the target tension value. Then, in steps 27 and 28, metal-in T 2 (> T 1 ) (for example, 1.
After 5 seconds), the plate thickness dynamic control of the i-1 stand is started (see FIG. 2D). This gives i-1
The work roll gap of the stand is corrected (Fig. 2
(C)). Further, in steps 25 and 26, the target tension value is changed to another target value after the metal-in T 3 (> T 2 ) (for example, 4 seconds) has elapsed (see FIG. 2A). This change is not stepwise but made asymptotic by using a ramp function, an exponential function, etc., and is returned to the optimum tension value for the threading of the intermediate portion of the material (see FIG. 2A). By this operation, it is possible to prevent a sharp tension change at the tip portion, and suppress a plate thickness change (see FIG. 2 (e)). The tension target value after T 3 is set to a tension (usually smaller than the tension at the material front end threading) so as not to cause work roll flaws due to the material tail edge when it is threaded.

【0018】本発明の適用により、制御前(図5
(e))に比べ制御後(図2(e))の方が、張力の急
峻な変動がなく、材料先端部での板厚偏差を増加させる
ことなく、オフゲージ量の0化を達成した。
By applying the present invention, before control (see FIG.
Compared to (e), after the control (FIG. 2 (e)), the off-gauge amount was reduced to zero without a sharp change in tension and without increasing the plate thickness deviation at the material tip.

【0019】[0019]

【発明の効果】上述したように、本発明によれば、メタ
ル先端部の急峻な張力変動を抑制して、板厚精度を向上
させることができる。
As described above, according to the present invention, it is possible to suppress sharp tension fluctuations at the metal tip and improve the plate thickness accuracy.

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

【図1】 本発明の板厚制御方法の制御フロー図であ
る。
FIG. 1 is a control flow chart of a plate thickness control method of the present invention.

【図2】 本発明の制御動作を示すタイムチャートであ
る。
FIG. 2 is a time chart showing a control operation of the present invention.

【図3】 圧延スタンドのプロセス概略図である。FIG. 3 is a process schematic diagram of a rolling stand.

【図4】 従来の制御フロー図である。FIG. 4 is a conventional control flow chart.

【図5】 従来の制御動作を示すタイムチャートであ
る。
FIG. 5 is a time chart showing a conventional control operation.

【符号の説明】[Explanation of symbols]

1 圧延スタンド、2 出側板厚計、3 張力制御装置
(ルーパ)、4 圧延材料、5 通板方向、6 板厚制
御装置(圧下装置)
1 rolling stand, 2 delivery side plate thickness gauge, 3 tension control device (looper), 4 rolling material, 5 threading direction, 6 plate thickness control device (roll down device)

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 複数個の圧延スタンド及び複数個のスタ
ンド間張力制御装置を有する熱間タンデム圧延機におけ
る板厚制御方法において、任意のスタンド間を圧延材料
が通過した後、該当するスタンド間張力制御装置が制御
開始する時点の張力実績値を目標張力値として張力制御
を行い、所定の時間後、当該スタンド間の目標張力値を
前記目標値とは別の値に次第に変化するように変更し圧
延材料先端部張力変動による圧延材料先端部変動を抑制
することを特徴とする板厚制御方法。
1. A plate thickness control method for a hot tandem rolling mill having a plurality of rolling stands and a plurality of inter-stand tension control devices, wherein the tension between the stands after the rolling material has passed between arbitrary stands. Tension control is performed using the actual tension value at the time when the control device starts control as the target tension value, and after a predetermined time, the target tension value between the stands is changed so as to gradually change to a value different from the target value. A plate thickness control method, characterized in that fluctuations in the rolling material tip portion due to fluctuations in the rolling material tip portion are suppressed.
JP6219194A 1994-09-13 1994-09-13 Method for controlling thickness in hot tandem rolling mill Withdrawn JPH0890034A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6219194A JPH0890034A (en) 1994-09-13 1994-09-13 Method for controlling thickness in hot tandem rolling mill

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6219194A JPH0890034A (en) 1994-09-13 1994-09-13 Method for controlling thickness in hot tandem rolling mill

Publications (1)

Publication Number Publication Date
JPH0890034A true JPH0890034A (en) 1996-04-09

Family

ID=16731689

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6219194A Withdrawn JPH0890034A (en) 1994-09-13 1994-09-13 Method for controlling thickness in hot tandem rolling mill

Country Status (1)

Country Link
JP (1) JPH0890034A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102941232A (en) * 2012-11-12 2013-02-27 东北大学 Method for controlling hot continuous rolling finish rolling process

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102941232A (en) * 2012-11-12 2013-02-27 东北大学 Method for controlling hot continuous rolling finish rolling process

Similar Documents

Publication Publication Date Title
JPH03238113A (en) Rolling of material at front and rear end of workpiece to predetermined size
JPH0890034A (en) Method for controlling thickness in hot tandem rolling mill
JP6663872B2 (en) Rolling mill control device, rolling mill control method, and rolling mill control program
JP3506120B2 (en) Method of changing rolling load distribution of tandem rolling mill
JP2003136108A (en) Hot rolling system and method for threading run out table and method for manufacturing rolled plate
JPH08267114A (en) Rolling method for controlling edge drop in cold rolling
JPH09295020A (en) Flying thickness changing method of metal plate in continuous type tandem rolling mill
JP4019035B2 (en) Thick plate rolling method
JP2670164B2 (en) Method of reducing L warpage in cold rolling
JP3506098B2 (en) Shape control method and apparatus in sheet rolling
JP2004001031A (en) Method for cold-rolling metal plate
JP2920896B2 (en) Edge drop control method
JPH0679325A (en) Method for rolling welded part of continuous cold mill
KR100328930B1 (en) The hot rolling method for controlling the thickness and in the top end of strip
JPH0679326A (en) Method for rolling welded part of continuous cold mill
JPH105807A (en) Cold rolling method of metal sheet at shifting work roll during rolling
JP2867907B2 (en) Thickness control method in cold rolling
JP2763490B2 (en) Method of controlling tension between stands of rolling mill
JPH08150406A (en) Thickness controller for cold tandem mill
JPS6339321B2 (en)
JPH08141614A (en) Method for controlling thickness in hot rolling
JPH11123427A (en) Method for controlling shape of rolled stock and device therefor
JP2001162303A (en) Method and device for manufacturing hot-rolled steel strip
JPH05337531A (en) Automatic plate thickness controlling method for rolling machine whose speed is accelerated/decelerated
JPH09206815A (en) Method for controlling edge drop in cold rolling

Legal Events

Date Code Title Description
A300 Withdrawal of application because of no request for examination

Free format text: JAPANESE INTERMEDIATE CODE: A300

Effective date: 20011120