JP3774957B2 - Winding method of continuous hot rolled metal strip - Google Patents

Description

（１）式中、Ｃ_e （力の伝播速度）は金属帯内の音速であり、下記の（２）式で表される。
【００１６】
【数２】

（２）式中、Ｅは金属帯のヤング率、ρは金属帯の密度である。
切断時の通板テーブル上の金属帯は、図１に示すような、一端固定（仕上圧延機２）、他端自由（シャー３）のモデルで表すことができ、この境界条件において前記（１）式を解くと、固定端を始点とする位置ｘでの変位ｕ_x は、下記の（３）式で表され、位置ｘでの応力σ_x は下記の（４）式で表される。
【００１７】
【数３】

【００１８】
【数４】

（３），（４）式中、ｌは固定端−自由端距離でここでは１６０ｍ、ｔは時間、Ａ_n は積分定数であり、ω（固有振動数）は下記の（５）式で表される。
【００１９】
【数５】

そして、初期条件〔ｔ＝０のときｕ₀ （ｘ＝０での単位長さ当たりの変位）＝２ｋｇ／ｍｍ² 〕を（３），（４）式に代入して積分定数Ａ_n を求めた。この積分定数Ａ_n を用い、（３），（４）式から、時間ｔ＝０，０．０２３，０．０４６，０．０５０，０．０６８〔秒〕での、各位置Ｘにおける変位ｕ_x および応力σ_x を求めた。その結果を図２に示す。
【００２０】
この結果から分かるように、初期張力は自由端から失われて、固定端から圧縮応力が生じている。そして、この圧縮応力が座屈限界を超える大きさとなった時に、通板テーブル上の金属帯にウエービングが生じると推定される。また、この圧縮応力は固定端から自由端へと伝搬する。すなわち、ウエービングは、固定端である仕上圧延機２側の部分に先ず発生して、自由端であるシャー３側の部分に伝搬していく。
【００２１】
そして、請求項２および３の方法では、切断時には、通板テーブルによる金属帯の送り速度が、圧延機の出側直後での金属帯の移動速度より遅くなっているため、通板テーブル上の金属帯に圧延機側の向きの力がかかる。これにより、仕上圧延機側の部分に生じたウエービングがシャー側へ伝搬する速度を遅らせることができる。
【００２２】
したがって、切断された後行材の先端部分をウエービングが生じていない状態でコイラーに巻き取ることができる。そして、先端部分が巻き取られた後には、巻取りコイラー直前のピンチロールと仕上圧延機との間に張力が発生するため、仕上圧延機側に生じていたウエービングも解消される。
【００２３】
なお、一般に、通板テーブルによる金属帯の送り速度は、仕上圧延機の出側直後での金属帯の移動速度と同じに設定され、仕上圧延機から出てきた金属帯がスムーズに（圧延機の出側直後での金属帯の移動速度で）搬送されるようにしてあり、この方法においても通常時（切断直前まで）はそのようにしておく。
【００２４】
【発明の実施の形態】
以下、本発明の実施形態について説明する。
図３は、本発明の方法が適用される連続熱間圧延ラインの巻取り側設備列を示す概略構成図である。
【００２５】
この設備列は、粗圧延されたシートバーＳ₀ が導入されて、先行材の尾端と後行材の先端を接合する接合装置１と、接合されたシートバーを仕上圧延する圧延機（仕上圧延機）２と、仕上圧延後の鋼帯（金属帯）Ｓを所定長さで切断するシャー３と、シャー３の入側直前に配置されたピンチロール４と、ラインに沿って直列に配置されたNo.1コイラーＫ₁ およびNo.2コイラーＫ₂ と、No.1コイラーＫ₁ の入側直前に配置されたピンチロール５と、No.2コイラーＫ₂ の入側直前に配置されたピンチロール６とで構成されている。この設備列により、連続的に仕上圧延された鋼帯Ｓは、シャー３で所定長さに切断されながら、No.1コイラーＫ₁ およびNo.2コイラーＫ₂ で交互に複数のコイルに巻き取られる。
【００２６】
また、下流側の圧延機２の出側には、通板テーブル７が配置されている。この通板テーブル７は、多数のローラ７ａをラインに沿って配置したローラテーブルであり、全てのローラ７ａを同じ回転速度で回転させて、通常は、この通板テーブル７による鋼帯Ｓの送り速度を、圧延機２の出側直後での鋼帯Ｓの移動速度と同じに設定することにより、圧延機２から出てきた鋼帯Ｓがスムーズに搬送されるようにしてある。
【００２７】
このような連続熱間圧延においては、巻取り対象となっているコイラー（ここではNo.1コイラーＫ₁ ）と圧延機２との間の鋼帯Ｓに所定の張力が付与されて、安定的な通板および巻取りを行っている。この張力はコイラーの巻取りトルクを所定値に設定することにより維持されており、ピンチロール４の圧下力は、通常時には、圧延機２側から搬送されてくる鋼帯Ｓをシャー３にスムーズに導入させるために適切な値に設定されている。また、ピンチロール４にはトルクが付与されず、圧延機２側から搬送されてくる鋼帯Ｓに駆動されて、鋼帯Ｓをコイラー側へ送り出す方向に回転している。
【００２８】
そして、鋼帯Ｓをシャー３により切断する直前に、ピンチロール４の圧下力を所定値Ｐまで増大する。また、ピンチロール４の各ロールに駆動トルクを付与し、上側ロール４１のトルクを所定値Ｑ_u とし、下側ロール４２のトルクを所定値Ｑ_b とする。さらに、通板テーブル７による鋼帯Ｓの送り速度が、圧延機２の出側直後での鋼帯Ｓの移動速度より遅くなるように、ローラ７ａの回転速度を設定する。
【００２９】
前記所定値Ｐは、切断直前に巻取りコイラーＫ₁ と圧延機２との間の鋼帯Ｓにかかっている張力をＴとし、鋼帯Ｓとピンチロール４との間の動摩擦係数をμ₀ として、Ｐ＝Ｔ／μ₀ となる値とする。
【００３０】
ここで、ピンチロール４と切断された鋼帯の後行材Ｓ₁ との間に生じる運動摩擦力ｆはｆ＝μ₀ ・Ｐで表されるが、Ｐ＝Ｔ／μ₀ と設定することで、理論的には、切断直前の張力Ｔと同じ大きさの摩擦力が、切断した瞬間に、後行材とピンチロールとの間に生じる。これにより、後行材Ｓ₁ はピンチロール４にスリップすることなく押さえ付けられながら、切断により生じる力Ｆに対抗してコイラー側へ送り出される。
【００３１】
前記所定値Ｑ_u は、前記張力Ｔと上側ロール４１のロール半径ｒ_u とにより、Ｑ_u ＝ｒ_u ・Ｔ／２で表される値、前記所定値Ｑ_b は、前記張力Ｔと下側ロール４２のロール半径ｒ_b とにより、Ｑ_b ＝ｒ_b ・Ｔ／２で表される値とする。これにより、切断直後に、ピンチロール４で挟持された後行材Ｓ₁ は、切断直前の張力Ｔと同じ力で引っ張られるため、ピンチロール４より上流側の部分にウエービングが発生しないようにすることができる。なお、上下各面に同じ張力Ｔ／２が作用するため変形などの問題は生じない。
【００３２】
また、通板テーブル７による鋼帯Ｓの送り速度が、圧延機２の出側直後での鋼帯Ｓの移動速度より遅いため、通板テーブル７上の鋼帯Ｓに圧延機２側の向きの力がかかる。これにより、ピンチロール４より上流側の鋼帯Ｓにウエービングが発生した場合でも、圧延機２側に留めて、ピンチロール４側へ伝搬する速度を遅らせることができる。
【００３３】
したがって、ピンチロール４の入側直前で鋼帯Ｓに２枚折れが生じることなく、コイラーＫ₁ ，Ｋ₂ による巻取りが安定的に行われる。
なお、前記実施形態では、鋼帯Ｓをシャー３により切断する直前に、(1) ピンチロール４の圧下力を所定値Ｐまで増大すること、(2) ピンチロール４の各ロールに駆動トルクを付与すること、(3) 通板テーブル７による鋼帯Ｓの送り速度を圧延機２の出側直後での鋼帯Ｓの移動速度より遅くすることを全て行っているが、少なくとも二つ、例えば (1) と (2) 、あるいは (1) と (3) を行ってもよい。
【００３４】
この場合には、ピンチロール４と圧延機２との間に十分な張力は作用しないため、▲１▼〜▲３▼を同時に行った場合と比べてウエービングが生じる可能性が高くなるが、その場合でも、鋼種や板厚によっては、後行材Ｓ₁ の先端部分をウエービングが生じていない状態でコイラーに巻き取ることができる。そして、先端部分が巻き取られた後には、ピンチロール４と圧延機２との間に張力が発生するため、圧延機２側に生じていたウエービングも解消される。
【００３５】
また、通板テーブル７による鋼帯Ｓの送り速度Ｖ₁ を、圧延機２の出側直後での鋼帯Ｓの移動速度Ｖ₂ よりどの程度遅くすることが好ましいかは、鋼種や板厚などによって異なるが、例えば、Ｖ₁ ＝（０．９５〜０．９７）Ｖ₂ とすることが好ましい。
【００３６】
【実施例】
図３の設備列により、連続熱間圧延および圧延された鋼帯の巻取り・切断を実際に行った。鋼帯の切断時の２枚折れ発生防止対策としては、下記の表１に示す設定を行った。また、圧延後の板厚が１〜２．０ｍｍの場合と、２．１〜５ｍｍの場合に分けて、２枚折れ発生（平均値）率を計算した。その結果を、表１に併せて示す。
【００３７】
ここでいう「２枚折れ発生率」とは、各方法毎に、総巻取りコイル数に対して、２枚折れが生じた回数の比率を百分率で示した値である。
＜２枚折れ発生防止対策＞
▲１▼鋼帯の切断時に、ピンチロール４の圧下力をＴ／μ₀ まで増大する。
【００３８】
▲２▼鋼帯の切断時に、ピンチロール４の上側ロール４１のトルクを（ｒ_u ・Ｔ／２）に、下側ロール４２のトルクを（ｒ_b ・Ｔ／２）にする。
▲３▼鋼帯の切断時に、通板テーブル７による鋼帯Ｓの送り速度を、圧延機２の出側直後での鋼帯Ｓの移動速度の９６％とする。
【００３９】
【表１】

これらの結果から分かるように、▲１▼〜▲３▼の全ての対策を施したNo.6では、２枚折れ発生率が“０”となった。また、▲１▼と▲２▼または▲３▼との組合せ（No.4，No.5）によっても、２枚折れ発生率は２０％以下となり、効果は高いことが分かった。また、板厚が厚い場合には、▲３▼の対策のみでも２枚折れ発生率を２０％と小さくできることが分かった。
【００４０】
【発明の効果】
以上説明したように、請求項１の方法によれば、シャーによる切断時に、後行材は、シャー入側直前のピンチロールにスリップすることなく押さえ付けられながら、切断により生じる力（仕上圧延機側向きの力）に対抗してコイラー側へ送り出される。
【００４１】
また、切断直後に、シャー入側直前のピンチロールで挟持された後行材が、切断直前の張力と同じまたはほぼ同じ力で引っ張られるため、ウエービングが発生しないようにすることができる。これにより、前記ピンチロールの入側直前で鋼帯に２枚折れが発生する確率を著しく低くすることができるため、コイラーによる巻取りが安定的に行われる。
【００４２】
請求項２および３の方法によれば、シャーによる切断時に、後行材にウエービングが生じても、このウエービングが先端部分まで伝搬されないうちに、先端部分をコイラーに巻き付けることができ、その後は後行材に張力が作用する。これにより、前記ピンチロールの入側直前で鋼帯に２枚折れが発生する確率を低くすることができるため、コイラーによる巻取りの安定性が向上する。
【００４３】
特に請求項３の方法では、請求項１の方法によっても発生が避けられなかったウエービングを、シャー入側直前のピンチロールに到達させないようにすることができる。これにより、前記ピンチロールの入側直前で鋼帯に２枚折れが発生する確率を著しく低くすることができるため、コイラーによる巻取りが安定的に行われる。
【図面の簡単な説明】
【図１】切断時の金属帯の挙動解析のモデルを示す概要図である。
【図２】図１のモデルによる金属帯の変位と応力分布の時系列計算結果を示すグラフである。
【図３】本発明の方法が適用される連続熱間圧延ラインの巻取り側設備列を示す概略構成図である。
【図４】従来の連続熱間圧延ラインにおける、鋼帯の切断時の状態を示す概要図である。
【符号の説明】
２ 圧延機（仕上圧延機）
３ シャー
４ ピンチロール（シャー入側直前のピンチロール）
５ ピンチロール（巻取りコイラー直前のピンチロール）
６ ピンチロール（巻取りコイラー直前のピンチロール）
７ 通板テーブル
Ｋ₁ No.1コイラー
Ｋ₂ No.2コイラー
Ｓ 鋼帯（金属帯）
Ｓ₁ 後行材[0001]
BACKGROUND OF THE INVENTION
In the present invention, a metal strip that has been continuously hot-rolled and exited from a finishing mill is cut by a shear with a predetermined length, and the cut preceding material and succeeding material are arranged in series along the line. The present invention also relates to a method for winding a continuous hot-rolled metal strip that is alternately wound by a plurality of coilers.
[0002]
[Prior art]
Conventionally, hot rolling of steel strip has been performed batchwise for each slab and wound around one coil. Recently, however, a sheet bar obtained by roughly rolling a slab is joined and continuously rolled. Continuous hot rolling is being performed. In this continuous hot rolling, the steel strip after finish rolling is cut with a shear at the joining position, and the cut preceding material and succeeding material are alternately coiled by a plurality of coilers arranged along the line. Winding up is performed.
[0003]
In such continuous hot rolling, stable feeding and winding are performed by applying tension to the steel strip between the winding coiler and the finish rolling mill. Then, as shown in FIG. 4, the steel strip S from the finish rolling mill 2 is sandwiched between the pinch roll 5 just before the winding coiler and the pinch roll 4 just before the shear entry side, and is cut by the shear 3. Yes.
[0004]
Therefore, until immediately before cutting by the shear 3, the steel strip S between the finishing mill 2 and the winding coiler is stretched within the elastic limit by tension. Lost and a force is generated on the succeeding material S ₁ to return to the finishing mill 2 side. As a result, the trailing material S ₁ on the passing plate table 7 may be waved. In severe cases, the trailing material S ₁ is folded in two (folded along the passing plate direction) and remains as it is. There is a case where the pinch roll 4 is bitten, and if it is wound as it is, the steel strip may be broken during winding, and there is a possibility that a plate passing accident may occur.
[0005]
[Problems to be solved by the invention]
The present invention has been made paying attention to such problems of the prior art, and at the time of cutting with a shear, it does not cause waving to the subsequent material cut by the shear, It is an object of the present invention to provide a method capable of preventing two steel sheets from being folded immediately before the pinch roll is placed on the steel sheet by making it not to exist immediately before the pinch roll placed on the steel sheet. And
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 is directed to a metal strip that has been continuously hot-rolled and exited from a finishing mill, and has a predetermined length and a pinch roll and a shear inlet side immediately before the winding coiler. A continuous hot rolled metal strip that is sandwiched between a previous pinch roll and cut by a shear, and the cut preceding material and subsequent material are alternately wound by a plurality of coilers arranged in series along the line. in the winding method provides a winding method of continuous hot rolling metal strip characterized by comprising the following configuration (1) and (2).
(1) At the time of cutting, the rolling force of the pinch roll immediately before the shear entry side is set to a value equal to or greater than a predetermined value P expressed by the following equation (A).
(2) the during cutting is substantially equal or equal to the predetermined value Q _u represented torque of the upper roll of the pinch roll just before Shah entry side in (B ₁₎ the following equation, the following torque of the lower roll of (B ₂₎ substantially equal or equal to the predetermined value Q _b of the formula, set respectively.
[0007]
P = T / μ ₀ (A)
Q _u = _ru · T / 2 (B ₁ )
Q _b = r _b · T / 2 (B ₂ )
(However, T is the tension applied to the metal strip between the winding coiler and the finishing mill immediately before cutting, and μ ₀ is between the pinch roll and the metal strip immediately before the shear entry side. dynamic friction coefficient der Ri, r _u is a roll radius of said upper roll, r _b is Ru roll radius der of the lower roll.)
Before cutting, the pinch roll immediately before entering the shear is driven by the metal strip conveyed from the finishing mill side and rotated in the direction of feeding the metal strip to the coiler side. Produces a force F returning to the finishing mill. In order to counter the force F and send the trailing material to the coiler side, it is necessary to press the trailing material with the pinch roll.
[0008]
Here, the kinetic frictional force f generated between the pinch roll and the succeeding material of the cut steel strip is expressed by f = μ ₀ · P, but by setting P = T / μ ₀ Specifically, a frictional force having the same magnitude as the tension T immediately before cutting is generated between the succeeding material and the pinch roll at the moment of cutting. As a result, the succeeding material is fed to the coiler side against the force F generated by cutting while being pressed against the pinch roll without slipping, so that the degree of occurrence of waving can be reduced.
[0009]
In addition, although the said effect becomes so large that the said rolling force at the time of a cutting | disconnection is large, if a rolling force is too large, it will become easy to meander the following material, and it will cause a winding defect when winding with a coiler. A value that does not cause a bad winding failure is taken as the upper limit.
[0011]
Further, according to the configuration (2) , immediately after cutting, the trailing material sandwiched by the pinch roll immediately before the shear entry side is pulled with the same or almost the same tension as that immediately before the cutting, so that waving does not occur. can do.
In the invention according to claim 2, the metal strip that has been continuously hot-rolled and exited from the finishing mill is sandwiched between the pinch roll immediately before the winding coiler and the pinch roll immediately before the shear entrance at a predetermined length. Te was cut with shears, the cut preceding material and the following material, the winding method of continuous hot rolling metal strip wound alternately a plurality of coiler arranged in series along the line, the configuration ( Provided is a continuous hot rolled metal strip winding method characterized by comprising 1) and the following configuration (3) .
(3) At the time of cutting, the feeding speed of the metal strip by the sheet passing table arranged on the exit side of the finishing mill is set slower than the moving speed of the metal strip immediately after the exit side of the finishing mill.
[0012]
In the invention according to claim 3, the metal strip that is continuously hot-rolled and comes out of the finishing mill is sandwiched between the pinch roll immediately before the winding coiler and the pinch roll immediately before the shearing side at a predetermined length. Te was cut with shears, the cut preceding material and the following material, the winding method of continuous hot rolling metal strip wound alternately a plurality of coiler arranged in series along the line, the configuration ( 1) to (3) are provided, and a method for winding a continuous hot rolled metal strip is provided.
[0014]
Here, the behavior of the metal band on the sheet passing table at the time of cutting is analyzed as a longitudinal vibration phenomenon of the elastic band.
The vibration equation of the longitudinal wave of the plate is expressed by the following equation (1):
[0015]
[Expression 1]

In the formula (1), C _e (force propagation speed) is the speed of sound in the metal band, and is represented by the following formula (2).
[0016]
[Expression 2]

In the formula (2), E is the Young's modulus of the metal band, and ρ is the density of the metal band.
The metal strip on the sheet passing table at the time of cutting can be represented by a model of one end fixed (finishing mill 2) and the other end free (shear 3) as shown in FIG. ) solving equation displacement u _x in the position x of the fixed end and the starting point is represented by the following expression (3), the stress sigma _x at position x is expressed by the following equation (4).
[0017]
[Equation 3]

[0018]
[Expression 4]

In equations (3) and (4), l is a fixed end-free end distance, here 160 m, t is time, _An is an integral constant, and ω (natural frequency) is expressed by the following equation (5). Is done.
[0019]
[Equation 5]

Then, by substituting the initial condition [u ₀ (displacement per unit length when x = 0) = 2 kg / mm ² ] when t = 0 into the equations (3) and (4), the integral constant _An is obtained. It was. Using this integration constant _{A n, (3), (} 4) from the equation, at time t = 0,0.023,0.046,0.050,0.068 (seconds), the displacement u at each position X _x and stress σ _x were determined. The result is shown in FIG.
[0020]
As can be seen from this result, the initial tension is lost from the free end, and compressive stress is generated from the fixed end. And when this compressive stress becomes the magnitude | size exceeding a buckling limit, it will be estimated that a webbing arises in the metal strip on a sheet passing table. Further, this compressive stress propagates from the fixed end to the free end. That is, waving first occurs in the portion on the finishing mill 2 side, which is a fixed end, and propagates to the portion on the shear 3 side, which is a free end.
[0021]
And in the method of Claim 2 and 3 , at the time of a cutting | disconnection, since the feeding speed of the metal strip by a sheet passing table is slower than the moving speed of the metal band immediately after the exit side of a rolling mill, on the sheet passing table A force in the direction of the rolling mill is applied to the metal strip. Thereby, the speed which the waving produced in the part by the side of a finishing mill propagates to the shear side can be delayed.
[0022]
Therefore, the leading end portion of the cut following material can be wound around the coiler in a state where no webbing occurs. Then, after the tip portion is wound, tension is generated between the pinch roll immediately before the winding coiler and the finishing mill, so that the waving that has occurred on the finishing mill side is also eliminated.
[0023]
In general, the feeding speed of the metal strip by the sheet passing table is set to be the same as the moving speed of the metal strip immediately after the exit side of the finish rolling mill, and the metal strip coming out of the finish rolling mill is smooth (rolling mill). The metal band is transported at a moving speed immediately after the exit side, and this method is also used in this method at normal times (until just before cutting).
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described.
FIG. 3 is a schematic configuration diagram showing a winding side equipment row of a continuous hot rolling line to which the method of the present invention is applied.
[0025]
In this equipment row, a roughly rolled sheet bar S ₀ is introduced, a joining device 1 for joining the tail end of the preceding material and the tip of the succeeding material, and a rolling mill (finishing) for finishing and rolling the joined sheet bar. (Rolling mill) 2, a shear 3 that cuts a steel strip (metal strip) S after finish rolling at a predetermined length, a pinch roll 4 that is disposed immediately before entering the shear 3, and is arranged in series along the line No. 1 coiler K ₁ and No. 2 coiler K ₂ , pinch roll 5 placed just before the entrance side of No. 1 coiler K ₁ , and just before the entrance side of No. 2 coiler K ₂ It consists of a pinch roll 6. The steel strip S, which is continuously finished and rolled by this equipment row, is wound around a plurality of coils alternately by No. 1 coiler K ₁ and No. 2 coiler K ₂ while being cut to a predetermined length by the shear 3. It is done.
[0026]
Further, a sheet passing table 7 is disposed on the exit side of the rolling mill 2 on the downstream side. This threading plate table 7 is a roller table in which a large number of rollers 7a are arranged along a line, and all the rollers 7a are rotated at the same rotational speed. By setting the speed to be the same as the moving speed of the steel strip S immediately after the exit side of the rolling mill 2, the steel strip S coming out of the rolling mill 2 is smoothly conveyed.
[0027]
In such continuous hot rolling, a predetermined tension is applied to the steel strip S between the coiler (here, No. 1 coiler K ₁ ) to be wound and the rolling mill 2 for stable Threading and winding. This tension is maintained by setting the coiler's winding torque to a predetermined value, and the rolling force of the pinch roll 4 normally causes the steel strip S conveyed from the rolling mill 2 side to smoothly move to the shear 3. It is set to an appropriate value for introduction. Further, no torque is applied to the pinch roll 4, and the pinch roll 4 is driven by the steel strip S conveyed from the rolling mill 2 side to rotate in the direction of feeding the steel strip S to the coiler side.
[0028]
Then, immediately before the steel strip S is cut by the shear 3, the rolling force of the pinch roll 4 is increased to a predetermined value P. Further, the driving torque applied to each roll of the pinch roll 4, the torque of the upper roll 41 to a predetermined value Q _u, the torque of the lower roll 42 with a predetermined value Q _b. Furthermore, the rotational speed of the roller 7a is set so that the feeding speed of the steel strip S by the sheet passing table 7 is slower than the moving speed of the steel strip S immediately after the exit side of the rolling mill 2.
[0029]
The predetermined value P is T, which is the tension applied to the steel strip S between the winding coiler K ₁ and the rolling mill 2 immediately before cutting, and the dynamic friction coefficient between the steel strip S and the pinch roll 4 is μ _0. Assuming that P = T / μ ₀ .
[0030]
Here, the kinetic frictional force f generated between the pinch roll 4 and the succeeding material S ₁ of the cut steel strip is expressed by f = μ ₀ · P, but is set to P = T / μ ₀ Theoretically, a frictional force having the same magnitude as the tension T immediately before cutting is generated between the succeeding material and the pinch roll at the moment of cutting. As a result, the succeeding material S ₁ is fed to the coiler side against the force F generated by the cutting while being pressed against the pinch roll 4 without slipping.
[0031]
Wherein the predetermined value Q _u, due the roll radius r _u of the tension T and the upper roll 41, the value represented by _{Q u = r u · T /} 2, the predetermined value Q _b, the tension T and the lower by a roll radius r _b of the roll 42, the value represented by _{Q b = r b · T /} 2. Thus, immediately after the cutting, the succeeding material S ₁ sandwiched between the pinch rolls 4 is pulled with the same force as the tension T immediately before the cutting, so that waving does not occur in a portion upstream of the pinch rolls 4. be able to. In addition, since the same tension T / 2 acts on the upper and lower surfaces, problems such as deformation do not occur.
[0032]
Further, since the feeding speed of the steel strip S by the sheet passing table 7 is slower than the moving speed of the steel strip S immediately after the exit side of the rolling mill 2, the steel strip S on the passing sheet table 7 is directed to the rolling mill 2 side. The power of. As a result, even when the webbing occurs in the steel strip S on the upstream side from the pinch roll 4, the speed of propagation to the pinch roll 4 side can be delayed by being held on the rolling mill 2 side.
[0033]
Accordingly, the steel strip S is not folded twice just before the pinch roll 4 enters, and the winding by the coilers K ₁ and K ₂ is stably performed.
In the embodiment, immediately before the steel strip S is cut by the shear 3, (1) the rolling force of the pinch roll 4 is increased to a predetermined value P, and (2) the driving torque is applied to each roll of the pinch roll 4. (3) The feeding speed of the steel strip S by the sheet passing table 7 is all made slower than the moving speed of the steel strip S immediately after the exit side of the rolling mill 2, but at least two, for example, (1) and (2) or (1) and (3) may be performed.
[0034]
In this case, since sufficient tension does not act between the pinch roll 4 and the rolling mill 2, there is a higher possibility that waving will occur as compared with the case where (1) to (3) are performed simultaneously. even if, depending on the steel type and plate thickness, it is possible to wind the leading end portion of the following material S ₁ to coiler in a state in which Uebingu has not occurred. And since the tension | tensile_strength generate | occur | produces between the pinch roll 4 and the rolling mill 2 after the front-end | tip part is wound, the waving which had arisen on the rolling mill 2 side is also eliminated.
[0035]
Moreover, it is preferable to make the feed speed V ₁ of the steel strip S by the sheet passing table 7 slower than the moving speed V ₂ of the steel strip S immediately after the exit side of the rolling mill 2, such as the steel type and the plate thickness. For example, V ₁ = (0.95 to 0.97) V ₂ is preferable.
[0036]
【Example】
With the equipment row in FIG. 3, continuous hot rolling and rolling / cutting of the rolled steel strip were actually performed. As a measure for preventing the occurrence of double sheet breakage when cutting the steel strip, the settings shown in Table 1 below were performed. Moreover, it divided into the case where the plate | board thickness after rolling was 1-2.0 mm, and the case of 2.1-5 mm, and calculated 2 sheet | seat folding generation | occurrence | production (average value) rate. The results are also shown in Table 1.
[0037]
The “two-sheet folding occurrence rate” here is a value indicating the ratio of the number of times of two-fold folding to the total number of winding coils for each method as a percentage.
<Two-sheet breakage prevention measures>
(1) When the steel strip is cut, the rolling force of the pinch roll 4 is increased to T / μ ₀ .
[0038]
▲ 2 ▼ at the time of cutting of the steel strip, the torque of the upper roll 41 of the pinch roll 4 to _{(r u · T / 2)} , the torque of the lower roll 42 _{(r b · T / 2)} .
(3) At the time of cutting the steel strip, the feeding speed of the steel strip S by the sheet passing table 7 is set to 96% of the moving speed of the steel strip S immediately after the exit side of the rolling mill 2.
[0039]
[Table 1]

As can be seen from these results, in No. 6 where all the measures (1) to (3) were taken, the rate of occurrence of two-sheet folding was “0”. In addition, the combination of (1) and (2) or (3) (No. 4, No. 5) also showed that the rate of occurrence of two-sheet folding was 20% or less, and the effect was high. Further, it was found that when the plate thickness is thick, the occurrence rate of folding of two sheets can be reduced to 20% only by the measure (3).
[0040]
【The invention's effect】
As described above, according to the method of claim 1, when cutting by the shear, the trailing material is pressed without being slipped to the pinch roll immediately before the shear entrance side, and the force generated by the cutting (finishing mill) It is sent to the coiler against the side force .
[0041]
Further , immediately after the cutting, the succeeding material sandwiched by the pinch roll immediately before the shear entry side is pulled with the same or substantially the same force as that immediately before the cutting, so that waving can be prevented from occurring. Thereby, since the probability that two sheets are broken in the steel strip immediately before the entrance side of the pinch roll can be significantly reduced, winding by the coiler is stably performed.
[0042]
According to the methods of claims 2 and 3 , even when waving occurs in the following material when cutting with a shear, the tip portion can be wound around the coiler before the waving is propagated to the tip portion. Tension acts on the row material. Thereby, since the probability that two sheets will bend | folded in a steel strip just before the entrance side of the said pinch roll can be made low, the stability of winding by a coiler will improve.
[0043]
In particular, in the method of claim 3 , it is possible to prevent the waving, which cannot be avoided even by the method of claim 1 , from reaching the pinch roll immediately before the shear entry side. Thereby, since the probability that two sheets are broken in the steel strip immediately before the entrance side of the pinch roll can be significantly reduced, winding by the coiler is stably performed.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a model of behavior analysis of a metal strip during cutting.
2 is a graph showing time-series calculation results of displacement and stress distribution of a metal strip according to the model of FIG.
FIG. 3 is a schematic configuration diagram showing a winding side equipment row of a continuous hot rolling line to which the method of the present invention is applied.
FIG. 4 is a schematic diagram showing a state at the time of cutting a steel strip in a conventional continuous hot rolling line.
[Explanation of symbols]
2 Rolling mill (finish rolling mill)
3 Shear 4 Pinch roll (Pinch roll just before entering the shear)
5 Pinch roll (Pinch roll just before winding coiler)
6 Pinch roll (Pinch roll just before winding coiler)
7 Plate plate table K ₁ No.1 coiler K ₂ No.2 coiler S Steel strip (metal strip)
S ₁ following material

Claims (3)

The metal strip that has been continuously hot rolled and exited from the finish rolling mill is sandwiched between a pinch roll immediately before the winding coiler and a pinch roll immediately before the shear entrance, and is cut by the shear. In the method of winding a continuous hot-rolled metal strip, the preceding material and the following material are alternately wound by a plurality of coilers arranged in series along the line.
At the time of cutting, the rolling force of the pinch roll immediately before the shear entry side is set to a value equal to or greater than the predetermined value P represented by the following formula (A), and the upper side of the pinch roll immediately before the shear entry side The torque of the roll is equal to or approximately equal to the predetermined value Q _u represented by the following equation (B ₁ ) , and the torque of the lower roll is equal to the predetermined value Q _b represented by the following equation (B ₂ ): A method for winding a continuous hot-rolled metal strip, characterized in that each is set to a substantially equal value .
P = T / μ ₀ (A)
Q _u = _ru · T / 2 (B ₁ )
Q _b = r _b · T / 2 (B ₂ )
(However, T is the tension applied to the metal strip between the winding coiler and the finishing mill immediately before cutting, and μ ₀ is between the pinch roll and the metal strip immediately before the shear entry side. dynamic friction coefficient der Ri, r _u is a roll radius of said upper roll, r _b is Ru roll radius der of the lower roll.) The metal strip that has been continuously hot rolled and exited from the finish rolling mill is sandwiched between a pinch roll immediately before the winding coiler and a pinch roll immediately before the shear entrance, and is cut by the shear. In the method of winding a continuous hot-rolled metal strip, the preceding material and the following material are alternately wound by a plurality of coilers arranged in series along the line.
At the time of cutting, the rolling force of the pinch roll immediately before entering the shear is set to a value equal to or greater than the predetermined value P represented by the following formula (A), and is arranged on the exit side of the finishing mill. and the feed rate of the metal strip by strip passing table, finishing mill of the delivery side immediately set slower than the moving speed of the metal strip in the winding method of continuous hot rolling metal strip you characterized by.
P = T / μ ₀ (A)
(However, T is, just before cutting, Ri tension der that had been given to the metal strip between the take-up coiler and finishing mill, μ ₀ is, between the pinch roll and the metal strip just before Shah entry side dynamic friction coefficient der of Ru.) The metal strip that has been continuously hot rolled and exited from the finish rolling mill is sandwiched between a pinch roll immediately before the winding coiler and a pinch roll immediately before the shear entrance, and is cut by the shear. In the method of winding a continuous hot-rolled metal strip, the preceding material and the following material are alternately wound by a plurality of coilers arranged in series along the line.
At the time of cutting, the rolling force of the pinch roll immediately before the shear entry side is set to a value equal to or greater than the predetermined value P represented by the following formula (A), and the upper side of the pinch roll immediately before the shear entry side The torque of the roll is equal to or approximately equal to the predetermined value Q _u represented by the following equation (B ₁ ) , and the torque of the lower roll is equal to the predetermined value Q _b represented by the following equation (B ₂ ): Set the values to approximately the same value, and set the feeding speed of the metal band by the sheet plate arranged on the exit side of the finishing mill slower than the moving speed of the metal band immediately after the exit side of the finishing mill. A method for winding a continuous hot-rolled metal strip.
P = T / μ ₀ (A)
Q _u = _ru · T / 2 (B ₁ )
Q _b = r _b · T / 2 (B ₂ )
(However, T is the tension applied to the metal strip between the winding coiler and the finishing mill immediately before cutting, and μ ₀ is between the pinch roll and the metal strip immediately before the shear entry side. a dynamic friction coefficient, r _u is a roll radius of said upper roll, r _b is the roll radius of the lower roll.)

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