JPH0671313A - Method for cooling work roll in control rolling of thick steel plate - Google Patents

Method for cooling work roll in control rolling of thick steel plate

Info

Publication number
JPH0671313A
JPH0671313A JP22609692A JP22609692A JPH0671313A JP H0671313 A JPH0671313 A JP H0671313A JP 22609692 A JP22609692 A JP 22609692A JP 22609692 A JP22609692 A JP 22609692A JP H0671313 A JPH0671313 A JP H0671313A
Authority
JP
Japan
Prior art keywords
rolling
work roll
cooling water
amount
rolled
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Withdrawn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
JP22609692A
Other languages
Japanese (ja)
Inventor
Sadao Morimoto
禎夫 森本
Kenichi Oe
憲一 大江
Tokuo Mizuta
篤男 水田
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.)
Kobe Steel Ltd
Original Assignee
Kobe Steel Ltd
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 Kobe Steel Ltd filed Critical Kobe Steel Ltd
Priority to JP22609692A priority Critical patent/JPH0671313A/en
Publication of JPH0671313A publication Critical patent/JPH0671313A/en
Withdrawn legal-status Critical Current

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  • Control Of Metal Rolling (AREA)
  • Metal Rolling (AREA)

Abstract

PURPOSE:To manufacture a rolled stock excellent in the dimensional accuracy of thickness by reducing the distortion of the roundness in the cross section accompanying to the non-uniformity of the interior temp. of the work rolls in stoppage of rotation from the completion of rolling till the start of the next rolling at the time of continuously executing the control rolling of a material to be rolled. CONSTITUTION:The non-uniformity of the interior temp. of the work rolls is reduced by decreasing the amount of cooling water which is jetted to the work rolls in stoppage of rotation from the completion of rolling till the start of the next rolling from about 80 to 30m<3>/h and rolling is started after returning the amount of cooling water to the prescribed amount of 80m<3>/h just before the next rolling. In this way, since temp. expansion difference that is generated based on ununiform cooling is eliminated and the cross section of the work roll is not distorted, periodic change of thickness in the longitudinal direction of the rolled stock is eliminated.

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、被圧延材の制御圧延に
おけるワークロール冷却方法に係り、より詳しくは、圧
延終了後の次の圧延に際して圧延材の長さ方向の板厚変
化の原因となる不均一な内部温度によるワークロールの
断面真円度の悪化を防止するようにした被圧延材の制御
圧延におけるワークロール冷却方法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work roll cooling method in controlled rolling of a material to be rolled, and more particularly, to a cause of a change in plate thickness in the longitudinal direction of the rolled material at the time of the next rolling after completion of rolling. The present invention relates to a work roll cooling method in controlled rolling of a material to be rolled, which prevents deterioration of the roundness of the cross section of the work roll due to the uneven internal temperature.

【0002】[0002]

【従来の技術】周知のように、被圧延材である厚鋼板の
圧延では、厚鋼板の圧延が完了してから次の圧延が開始
されるまでの圧延待ち時間中は、ワークロールの回転駆
動が停止される。そして、この圧延待ち時間中において
は、従来、ワークロールの回転を停止したままで圧延中
における場合と同量の冷却水を水噴射ノズルから噴射し
続けてワークロールを冷却している。制御圧延の場合の
待ち時間は、普通圧延に比較して長くなり、ワークロー
ルの冷却時間も長くなっている。
2. Description of the Related Art As is well known, in the rolling of a thick steel sheet as a material to be rolled, the work roll is driven to rotate during a rolling waiting time from the completion of rolling of the thick steel sheet to the start of the next rolling. Is stopped. Then, during this rolling waiting time, conventionally, the work roll is cooled by continuously injecting the same amount of cooling water from the water injection nozzle as in the case of rolling while the rotation of the work roll is stopped. The waiting time in the case of controlled rolling is longer than that in ordinary rolling, and the work roll cooling time is also longer.

【0003】[0003]

【発明が解決しようとする課題】ところで、回転を停止
したままの状態で冷却水を噴射してワークロールを冷却
し続けると、ワークロールに冷却水が直接当たっている
領域とそれ以外の領域とでは、表面からの奪熱量が相違
し、いわゆる偏冷却されるため、ワークロールの内部温
度が不均一となって熱膨張量に相違が生じるので、この
ワークロールの断面真円度が悪化していびつになってし
まう。
By the way, when cooling water is jetted while the rotation is stopped to continue cooling the work roll, there are a region where the cooling water directly hits the work roll and a region other than that. In this case, the amount of heat taken from the surface is different and so-called partial cooling is performed, so that the internal temperature of the work roll becomes non-uniform and the amount of thermal expansion is different. It becomes distorted.

【0004】例えば、回転中のワークロールの内部温度
分布説明図の図3aに示すように、ワークロールRが回
転しているときには、その回転中心を中心として外側ほ
ど高温度になる同心円状の等高温度分布を示すが、ワー
クロールRの回転が停止されると、回転停止5分経過後
のワークロールの内部温度分布説明図の図3bに示すよ
うに、冷却水が直接当たっている領域とそうでない領域
とでは、可成りの温度差が生じる。
For example, as shown in FIG. 3a of the drawing for explaining the internal temperature distribution of a rotating work roll, when the work roll R is rotating, concentric circles, etc., in which the temperature rises outward from the center of rotation of the work roll R, etc. Although a high temperature distribution is shown, when the rotation of the work roll R is stopped, as shown in FIG. 3b of the work roll internal temperature distribution explanatory diagram after 5 minutes of rotation stop, there is a region directly contacted with cooling water. A considerable temperature difference occurs between the other regions.

【0005】因みに、この温度差を熱膨張量に換算する
と、このワークロールRにはロール径で150μm程度
の寸法差が生じ、ワークロールRの断面真円度がいびつ
になってしまう。このような状態にあるワークロールR
によって被圧延材を圧延すると、ワークロールの内部温
度分布が図3aに示すようになるまでは、圧延材の長手
方向の板厚が周期的に変化し、板厚精度の優れた圧延材
を製造することができないという解決すべき課題が生じ
る。
Incidentally, when this temperature difference is converted into the amount of thermal expansion, the work roll R has a dimensional difference of about 150 μm in roll diameter, and the roundness of the cross section of the work roll R becomes distorted. Work roll R in this state
When the material to be rolled is rolled by, until the internal temperature distribution of the work roll becomes as shown in FIG. 3a, the plate thickness in the longitudinal direction of the rolled material cyclically changes to produce a rolled material with excellent plate thickness accuracy. There is a problem to be solved that cannot be done.

【0006】従って、本発明の目的とするところは、制
御圧延を連続して行うに際して、圧延待ち時間の間はロ
ール冷却水量を調整することによって、ワークロールの
断面真円度のいびつを防止することを可能ならしめる厚
鋼板の制御圧延におけるワークロール冷却方法を提供す
るにある。
Therefore, the object of the present invention is to prevent the work roll from having a roundness in cross section by adjusting the amount of roll cooling water during the rolling waiting time in the case of continuously performing controlled rolling. Another object of the present invention is to provide a work roll cooling method in the controlled rolling of thick steel plates that makes it possible.

【0007】[0007]

【課題を解決するための手段】本発明は、上記実情に鑑
み、ワークロールの回転停止中にその偏冷却の程度を少
なくするには、温度差を生じる原因となる冷却水の噴射
状況を変えれば良いことを知見してなしたものであっ
て、従って本発明に係る厚鋼板の制御圧延におけるワー
クロール冷却方法の特徴とするところは、被圧延材の制
御圧延を連続して行うに際して、圧延終了から次の圧延
開始までのワークロールの回転停止中は、該ワークロー
ルに噴射する冷却水量を少なくするか、あるいは冷却水
をかけないようにして、次の被圧延材の圧延開始直前か
ら、ワークロールに所定量の冷却水を噴射するところに
ある。
SUMMARY OF THE INVENTION In view of the above situation, the present invention can change the injection condition of cooling water that causes a temperature difference in order to reduce the degree of uneven cooling of the work roll while the rotation of the work roll is stopped. What has been found to be good, therefore, the feature of the work roll cooling method in the controlled rolling of the thick steel sheet according to the present invention is that when performing the controlled rolling of the material to be rolled continuously, During the rotation stop of the work roll from the end to the start of the next rolling, reduce the amount of cooling water sprayed to the work roll, or by not applying cooling water, immediately before the start of rolling the next material to be rolled, It is about to spray a predetermined amount of cooling water onto the work roll.

【0008】[0008]

【作用】本発明に係る厚鋼板の制御圧延におけるワーク
ロール冷却方法によれば、圧延終了から次の圧延開始ま
でのワークロールの回転停止中は、ワークロールに噴射
される冷却水量が少なくされるか、あるいは冷却水が噴
射されないので、待ち時間中にワークロールの偏冷却の
程度が少なくなるか、あるいは偏冷却されなくなる。そ
して、次の圧延開始の直前に冷却水が噴射されるとワー
クロールが回転されて圧延が開始されるので、内部温度
分布の不均一さが改善される。
According to the work roll cooling method in the controlled rolling of the thick steel plate according to the present invention, the amount of cooling water sprayed to the work roll is reduced during the rotation stop of the work roll from the end of rolling to the start of the next rolling. Or, since the cooling water is not sprayed, the degree of uneven cooling of the work roll is reduced or the uneven cooling is not performed during the waiting time. Then, when the cooling water is jetted immediately before the start of the next rolling, the work roll is rotated and the rolling is started, so that the non-uniformity of the internal temperature distribution is improved.

【0009】[0009]

【実施例】以下、本発明に係る被圧延材の制御圧延にお
けるワークロール冷却方法の実施例を、本発明の方法を
採用した圧延ラインの模式的構成説明図の図1と、被圧
延材である厚鋼板の長手方向の板厚変化説明グラフ図の
図2(図2aは本発明による場合を、図2bは従来法の
場合を示す)とを参照しながら説明する。
EXAMPLE An example of a work roll cooling method in the controlled rolling of a material to be rolled according to the present invention will be described below with reference to FIG. 1 which is a schematic configuration explanatory view of a rolling line adopting the method of the present invention and the material to be rolled. A description will be given with reference to FIG. 2 (FIG. 2a shows the case according to the present invention, and FIG. 2b shows the case of the conventional method) of a graph for explaining the change in the plate thickness in the longitudinal direction of a certain thick steel plate.

【0010】図に示す符号1は、上下にそれぞれワーク
ロールR1 ,R1 を有する粗圧延機であって、この粗圧
延機1の後工程側には、同じく上下にそれぞれワークロ
ールR2 ,R2 を有する仕上圧延機2が配設されてい
る。また、これら両圧延機1,2の間には、加熱炉Hで
加熱されて粗圧延機1から仕上圧延機2の方向に送られ
て圧延される厚鋼板Wの表裏面から冷却水を噴射して圧
延材の温度を調整する温調シャワー冷却設備3が配設さ
れている。
[0010] Reference numeral 1 shown in the figure, above and below a rough rolling mill having a work roll R 1, R 1, the process side after the rough rolling mill 1, also above and below the work rolls R 2, A finish rolling mill 2 having R 2 is arranged. In addition, cooling water is sprayed between the two rolling mills 1 and 2 from the front and back surfaces of a thick steel plate W that is heated in a heating furnace H and sent from the rough rolling mill 1 to the finish rolling mill 2 to be rolled. A temperature control shower cooling facility 3 for adjusting the temperature of the rolled material is provided.

【0011】さらに、これらワークロールR1 ,R1
2 ,R2 のそれぞれの外周面に向かって2方向からそ
れぞれ冷却水を噴射する水噴射ノズル4,4,4,4が
設けられている。なお、図示省略しているが、これら水
噴射ノズルはワークロールの長手方向に沿って所定の間
隔で複数配設されている。
Further, these work rolls R 1 , R 1 ,
Water jet nozzles 4, 4, 4, 4 for jetting cooling water from two directions toward the outer peripheral surfaces of R 2 and R 2 are provided. Although not shown, a plurality of these water jet nozzles are arranged at a predetermined interval along the longitudinal direction of the work roll.

【0012】このような圧延ラインで、例えば表1に示
すような温度・寸法条件で、厚鋼板を制御圧延で連続圧
延する場合には、上記温調シャワー冷却設備3による圧
延材の冷却に長時間を要するため、仕上圧延が完了して
から次の圧延開始までの圧延待ち時間は、例えば最長で
5分にもなる場合がある。
In such a rolling line, when the thick steel sheet is continuously rolled by controlled rolling under the temperature and dimension conditions shown in Table 1, for example, cooling of the rolled material by the temperature controlled shower cooling facility 3 is long. Since it takes time, the rolling waiting time from the completion of finish rolling to the start of the next rolling may be, for example, 5 minutes at the longest.

【0013】[0013]

【表1】 [Table 1]

【0014】圧延待ち時間中は、ワークロールR1 ,R
1 ,R2 ,R2 の回転駆動が停止され、回転駆動停止中
のワークロールR1 ,R1 ,R2 ,R2 に対して水噴射
ノズル4,4,4,4から冷却水が噴射され続けるが、
従来、噴射され続ける冷却水量が80m3 /hであった
のに対して、本実施例では冷却水量を30m3 /hに減
量して、それらの偏冷却の程度を少なくするようにし
た。
During the rolling waiting time, the work rolls R 1 , R
The rotation drive of 1 , R 2 and R 2 is stopped, and the cooling water is jetted from the water jet nozzles 4, 4, 4 and 4 to the work rolls R 1 , R 1 , R 2 and R 2 whose rotation is stopped. Continue to be
Conventionally, the amount of cooling water that is continuously jetted was 80 m 3 / h, whereas in the present embodiment, the amount of cooling water is reduced to 30 m 3 / h to reduce the degree of partial cooling.

【0015】そして、冷却水量を30m3 /hにしてワ
ークロールR1 ,R1 ,R2 ,R2を冷却し続け、次の
厚鋼板の圧延開始直前に冷却水量を80m3 /hにして
厚鋼板を圧延した場合と、ワークロールR1 ,R1 ,R
2 ,R2 の停止中も冷却水量を80m3 /hに保持して
冷却し続ける従来の方法で厚鋼板を圧延した場合とにつ
いて、圧延材の長手方向の板厚寸法の変化(幅方向の中
央部と、幅方向の両側の3か所)を調べた。その結果
は、図2(幅方向の一方をWS側として、また他法をD
S側として示している)に示す通りである。なお、圧延
材の板厚の測定には熱間γ線板厚計を用いた。
Then, the work rolls R 1 , R 1 , R 2 and R 2 are continuously cooled with the cooling water amount of 30 m 3 / h, and the cooling water amount is set to 80 m 3 / h immediately before starting rolling of the next thick steel plate. When rolling thick steel plate, and work rolls R 1 , R 1 , R
2 When the thick steel plate was rolled by the conventional method in which the cooling water amount was kept at 80 m 3 / h even when R 2 was stopped, and the conventional method was used, the change in the plate thickness dimension in the longitudinal direction of the rolled material (in the width direction The central portion and three locations on both sides in the width direction were examined. The results are shown in Fig. 2 (one in the width direction is on the WS side and the other method is D
(Shown as the S side). A hot γ-ray plate thickness meter was used to measure the plate thickness of the rolled material.

【0016】図2bに示す従来法によれば、圧延材の長
手方向の板厚変化に周期があり、この周期はワークロー
ルR1 ,R1 ,R2 ,R2 の外周長に一致しているのに
対して、図2aに示す本発明では板厚変化が少なく、し
かも周期性が認められない。
According to the conventional method shown in FIG. 2b, there is a cycle in the change in the plate thickness in the longitudinal direction of the rolled material, and this cycle corresponds to the outer peripheral length of the work rolls R 1 , R 1 , R 2 , R 2. On the other hand, in the present invention shown in FIG. 2a, there is little change in plate thickness and no periodicity is observed.

【0017】このように、従来法の場合に、圧延材の長
手方向の板厚変化に周期性があるのは、回転停止中のワ
ークロールR1 ,R1 ,R2 ,R2 に所定量の冷却水を
噴射し続けることにより、ワークロールR1 ,R1 ,R
2 ,R2 の内部温度に不均一な温度分布が生じ、これに
よってワークロールR1 ,R1 ,R2 ,R2 の断面真円
度が悪くなったことに起因することを確認した。
As described above, in the case of the conventional method, the change in the plate thickness in the longitudinal direction of the rolled material has a periodicity because the work rolls R 1 , R 1 , R 2 and R 2 which are not rotating have a predetermined amount. By continuously injecting the cooling water of the work rolls R 1 , R 1 , R
2, non-uniform temperature distribution in the interior temperature of the R 2 occurs, thereby it was confirmed that due to the cross-sectional roundness of the work roll R 1, R 1, R 2, R 2 is deteriorated.

【0018】ところで、以上では、冷却水量を少なくす
る例を説明したが、ワークロールの回転停止中は、冷却
水の噴射を停止するか、あるいは冷却水噴射ノズル(図
示省略)の向きを変えてワークロールR1 ,R1
2 ,R2 に冷却水がかからないようにすることも有効
であった。
By the way, although the example of reducing the amount of cooling water has been described above, while the rotation of the work roll is stopped, the injection of cooling water is stopped or the direction of the cooling water injection nozzle (not shown) is changed. Work rolls R 1 , R 1 ,
It was also effective to prevent cooling water from splashing on R 2 and R 2 .

【0019】しかしながら、冷却水の噴射を停止する
と、周囲の熱で冷却水噴射ノズルの内部の冷却水が蒸発
する。そして、冷却水中に含まれている不純物が堆積し
てこの水噴射ノズルが目詰まりを起こしたりする恐れが
あるので、実用的には水噴射ノズル4の向きを変える
か、あるいは上記実施例のように冷却水量を減量するこ
とが好ましい。なお、冷却水量の減量程度は、水噴射ノ
ズルが目詰まりを起こさない程度にすれば良く、その減
量程度については特に限定されるものではない。
However, when the injection of the cooling water is stopped, the cooling water inside the cooling water injection nozzle evaporates due to the surrounding heat. Then, there is a possibility that impurities contained in the cooling water may be accumulated and the water injection nozzle may be clogged. Therefore, in practice, the direction of the water injection nozzle 4 is changed, or the water injection nozzle 4 is changed as in the above embodiment. It is preferable to reduce the amount of cooling water. The amount of cooling water to be reduced may be such that the water injection nozzle does not become clogged, and the amount of reduction is not particularly limited.

【0020】[0020]

【発明の効果】以上詳述したように、本発明に係る厚鋼
板の制御圧延におけるワークロール冷却方法によれば、
ワークロールに噴射される冷却水量が少なくされるか、
あるいは噴射される冷却水量が少なくされる。そのた
め、待ち時間中にワークロールに生じる内部温度分布の
不均一の程度が少なくなり、ワークロールの断面真円度
が確保されるので、板厚変化の少ない圧延材を製造する
ことができる。
As described in detail above, according to the work roll cooling method in the controlled rolling of the thick steel plate according to the present invention,
Is the amount of cooling water sprayed to the work roll reduced?
Alternatively, the amount of cooling water injected is reduced. Therefore, the degree of non-uniformity of the internal temperature distribution generated in the work roll during the waiting time is reduced, and the roundness of the cross section of the work roll is secured, so that a rolled material with a small plate thickness change can be manufactured.

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

【図1】圧延ラインの模式的構成説明図である。FIG. 1 is a schematic configuration explanatory diagram of a rolling line.

【図2】図2aは本発明による厚鋼板の長手方向の板厚
変化説明グラフ図であり、また図2bは従来法による厚
鋼板の長手方向の板厚変化説明グラフ図である。
FIG. 2a is a graph for explaining a change in plate thickness in a longitudinal direction of a thick steel plate according to the present invention, and FIG. 2b is a graph for explaining a change in plate thickness in a longitudinal direction of a thick steel plate according to a conventional method.

【図3】図3aは回転中のワークロールの内部温度分布
説明図であり、また図3bは回転停止5分経過後のワー
クロールの内部温度分布説明図である。
FIG. 3a is an explanatory diagram of the internal temperature distribution of a rotating work roll, and FIG. 3b is an explanatory diagram of the internal temperature distribution of a work roll after 5 minutes of rotation stop.

【符号の説明】[Explanation of symbols]

1…粗圧延機、R1 …ワークロール 2…仕上圧延機、R2 …ワークロール 3…温調シャワー冷却設備 4…水噴射ノズル H…加熱炉 W…厚鋼板1 ... Coarse rolling mill, R 1 ... Work roll 2 ... Finishing mill, R 2 ... Work roll 3 ... Temperature controlled shower cooling equipment 4 ... Water injection nozzle H ... Heating furnace W ... Thick steel plate

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 被圧延材の制御圧延を連続して行うに際
して、圧延終了から次の圧延開始までのワークロールの
回転停止中は、該ワークロールに噴射する冷却水量を少
なくするか、あるいは冷却水をかけないようにして、次
の被圧延材の圧延開始直前から、ワークロールに所定量
の冷却水を噴射することを特徴とする厚鋼板の制御圧延
におけるワークロール冷却方法。
1. When continuously rolling controlled rolling of a material to be rolled, while the rotation of a work roll is stopped from the end of rolling to the start of the next rolling, the amount of cooling water sprayed to the work roll is reduced or cooled. A work roll cooling method in control rolling of a thick steel sheet, which comprises injecting a predetermined amount of cooling water onto a work roll immediately before starting rolling of the next material to be rolled without sprinkling water.
JP22609692A 1992-08-25 1992-08-25 Method for cooling work roll in control rolling of thick steel plate Withdrawn JPH0671313A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP22609692A JPH0671313A (en) 1992-08-25 1992-08-25 Method for cooling work roll in control rolling of thick steel plate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP22609692A JPH0671313A (en) 1992-08-25 1992-08-25 Method for cooling work roll in control rolling of thick steel plate

Publications (1)

Publication Number Publication Date
JPH0671313A true JPH0671313A (en) 1994-03-15

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Family Applications (1)

Application Number Title Priority Date Filing Date
JP22609692A Withdrawn JPH0671313A (en) 1992-08-25 1992-08-25 Method for cooling work roll in control rolling of thick steel plate

Country Status (1)

Country Link
JP (1) JPH0671313A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101308785B1 (en) * 2011-09-09 2013-09-17 중앙대학교 산학협력단 On-and-off cooling method for work roll in rolling mill and apparatus thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101308785B1 (en) * 2011-09-09 2013-09-17 중앙대학교 산학협력단 On-and-off cooling method for work roll in rolling mill and apparatus thereof

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