JP2003062647A - Direct rolling method for continuous cast steel piece - Google Patents
Direct rolling method for continuous cast steel pieceInfo
- Publication number
- JP2003062647A JP2003062647A JP2002059813A JP2002059813A JP2003062647A JP 2003062647 A JP2003062647 A JP 2003062647A JP 2002059813 A JP2002059813 A JP 2002059813A JP 2002059813 A JP2002059813 A JP 2002059813A JP 2003062647 A JP2003062647 A JP 2003062647A
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- Japan
- Prior art keywords
- slab
- zone
- cooling device
- surface temperature
- point
- 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.)
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- Continuous Casting (AREA)
- Metal Rolling (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、連続鋳造機により
鋳造された高温鋳片を、直接熱間圧延するか或いは表面
温度を中心温度と同じにする程度の保温・加熱を行った
後に熱間圧延するか、又は、連続鋳造機により鋳造され
た高温鋳片を加熱炉に装入して加熱した後に熱間圧延す
るか、何れかの方法（本発明ではこれらをまとめて「直
送圧延」と定義する）で鋼板を製造する直送圧延方法に
関し、詳しくは、表面性状に優れた鋼板を製造すること
ができる直送圧延方法に関するものである。TECHNICAL FIELD The present invention relates to a hot cast slab cast by a continuous casting machine, which is hot-rolled directly, or is heat-heated to such an extent that the surface temperature is the same as the center temperature. Rolling, or hot rolling after charging a high-temperature slab cast by a continuous casting machine into a heating furnace and then hot rolling, or either method (in the present invention, these are collectively referred to as "direct rolling"). The present invention relates to a direct feed rolling method for producing a steel sheet according to (Definition), and more specifically, to a direct feed rolling method capable of producing a steel sheet having excellent surface properties.
【０００２】[0002]
【従来の技術】連続鋳造機で鋳造された鋳片を、直接熱
間圧延するか或いは表面温度を中心温度と同じにする程
度の保温・加熱を行った後に熱間圧延する、所謂直接圧
延（Hot Direct Rolling：ＨＤＲプロセスとも云う）
や、連続鋳造機で鋳造された高温の鋳片を加熱炉に装入
して加熱後に熱間圧延する、所謂ホットチャージ圧延
（Hot Charged Rolling ：ＨＣＲプロセスとも云う）
は、工程の大幅な合理化や省エネルギ−及び歩留りの向
上が期待でき、今後更に開発が進められ発展が予想され
る。前述したように、本発明ではＨＤＲプロセス及びＨ
ＣＲプロセスをまとめて直送圧延と定義する。2. Description of the Related Art A slab cast by a continuous casting machine is directly hot-rolled, or hot-rolled after heat-retaining and heating such that the surface temperature is the same as the center temperature. Hot Direct Rolling: Also called HDR process)
Or so-called hot charged rolling (also called HCR process), in which a high temperature slab cast by a continuous casting machine is charged into a heating furnace and heated and then hot rolled.
Can be expected to greatly streamline the process, save energy and improve yield, and further development is expected in the future. As described above, according to the present invention, the HDR process and H
The CR process is collectively defined as direct rolling.
【０００３】しかしながら、ＨＤＲプロセスやＨＣＲプ
ロセスにより製造された鋼板には表面疵の発生が多く、
表面品質は従来の方法で製造された鋼板に比べて劣ると
云う問題がある。ここで従来の方法とは、連続鋳造後に
常温まで冷却した鋳片を無手入れのまま加熱炉に装入し
て圧延温度まで加熱し、次いで、熱間圧延して製造した
鋼板である。However, the steel plate produced by the HDR process or the HCR process often has surface defects,
There is a problem that the surface quality is inferior to that of the steel sheet manufactured by the conventional method. Here, the conventional method is a steel sheet manufactured by continuously charging a slab cooled to room temperature after continuous casting into a heating furnace without heating, heating it to a rolling temperature, and then hot rolling it.
【０００４】この表面疵の発生機構は、次のように考え
られる。即ち、ＨＤＲプロセス等の直送圧延では、鋳片
はその温度がＡr1点以上に保たれたまま、即ち、鋳片は
変態することなく凝固直後のオーステナイト結晶構造の
まま熱間圧延される。この場合のオーステナイト結晶粒
は粗大化しており、且つ、この結晶粒界には硫化物や窒
化物等の析出物が析出している。そのため、このオース
テナイト結晶粒界は結晶粒内に比較して極めて脆弱であ
り、熱間圧延時の加工歪みにより結晶粒界で割れが発生
し、この割れが鋼板の表面疵になる。ここで、Ａr1点と
は、オーステナイトがフェライトとパーライトとの混合
組織（以下「フェライト＋パーライト」と記す）に変態
する温度で、鋼組成にもよるが概ね７００℃以下の温度
である。The mechanism of occurrence of this surface flaw is considered as follows. That is, in the direct rolling such as the HDR process, the slab is hot-rolled while its temperature is maintained at the Ar1 point or higher, that is, the slab does not transform and has the austenite crystal structure immediately after solidification. In this case, the austenite crystal grains are coarsened, and precipitates such as sulfides and nitrides are precipitated at the crystal grain boundaries. Therefore, the austenite crystal grain boundaries are extremely fragile as compared with the inside of the crystal grains, and cracks occur at the crystal grain boundaries due to processing strain during hot rolling, and these cracks cause surface defects on the steel sheet. Here, the Ar1 point is a temperature at which austenite transforms into a mixed structure of ferrite and pearlite (hereinafter referred to as “ferrite + pearlite”), and is a temperature of about 700 ° C. or less depending on the steel composition.
【０００５】一方、従来の方法により鋼板を製造する場
合には、鋳片は一旦変態温度以下まで冷却されており、
鋳片はフェライト＋パーライト結晶構造に変態する。鋳
片は熱間圧延の際に圧延温度まで加熱されて、再度オー
ステナイト結晶構造に変態するが、この場合のオーステ
ナイト結晶粒は凝固直後のオーステナイト結晶粒に比較
して極めて微細であり、且つ、合計２回に亘る変態によ
り硫化物や窒化物等の析出物の存在位置とオーステナイ
ト結晶粒界の位置とは合致しなくなる。そのため、オー
ステナイト結晶粒界は特に脆化せず、熱間圧延において
も結晶粒界での割れが発生せず、表面性状の良好な鋼板
が得られる。On the other hand, when a steel sheet is manufactured by the conventional method, the slab is once cooled to below the transformation temperature,
The cast piece transforms into a ferrite + pearlite crystal structure. The slab is heated to the rolling temperature during hot rolling and is transformed into an austenite crystal structure again, but the austenite crystal grains in this case are extremely fine compared to the austenite crystal grains immediately after solidification, and the total. Due to the transformation performed twice, the positions of the precipitates such as sulfides and nitrides and the positions of the austenite grain boundaries do not match. Therefore, the austenite crystal grain boundaries are not particularly embrittled, cracks do not occur at the crystal grain boundaries even during hot rolling, and a steel sheet having good surface properties can be obtained.
【０００６】この観点に基づき、特開平４−２５３５０
５号公報には、連続鋳造中の鋳片をその表面温度がＡr1
点以下の温度になるまで冷却し、次いで、鋳片内部に存
在する未凝固相の顕熱及び潜熱を利用して１０００℃以
上に復熱させ、その後、熱間圧延するＨＤＲプロセスが
提案されている。この方法によれば、鋳片は一旦フェラ
イト＋パーライト結晶構造に変態するので、熱間圧延時
には微細なオーステナイト結晶粒となり、前述したＨＤ
Ｒプロセス特有の表面疵を防止することができる。Based on this point of view, JP-A-4-25350
No. 5 gazette discloses that a slab during continuous casting has a surface temperature of Ar1.
An HDR process has been proposed in which the temperature is cooled to a temperature below a point, then reheated to 1000 ° C. or higher by utilizing the sensible heat and latent heat of the unsolidified phase existing inside the slab, and then hot rolling. There is. According to this method, the slab temporarily transforms into a ferrite + pearlite crystal structure, so that it becomes fine austenite crystal grains during hot rolling, and the above-mentioned HD
Surface defects peculiar to the R process can be prevented.
【０００７】[0007]
【発明が解決しようとする課題】しかしながら、特開平
４−２５３５０５号公報では、鋳片表面をＡr1点以下の
温度まで冷却する際に、特別な冷却装置を用いず、通常
の二次冷却装置をそのまま活用し、冷却水量の増加によ
り鋳片を強冷却している。内部に多量の未凝固相を有す
る鋳片は本来冷却され難いことに加えて、冷却水量を増
加したと云えども通常の二次冷却装置の冷却能はそれほ
ど強くはならず、鋳片を短時間でＡr1点以下までに冷却
することは難しく、そのため、鋳片表層の極薄い部分の
みが目的温度まで冷却されるのみで、相変態が十分に行
われず、表面疵の改善効果が不十分であったり、又、目
的温度まで冷却しようとすると冷却時間が長くなり過ぎ
て未凝固相が減少し、その後の復熱が不足して所定の温
度まで昇温できず、鋳片の矯正時には鋳片表面に割れが
発生したり、又、省エネルギー効果の低下のみならず、
ＨＤＲプロセス自体が不可能になる等の問題点が発生す
る。ＨＤＲプロセスやＨＣＲプロセスでは、凝固・冷却
後の鋳片をできるだけ高温のまま熱間圧延機に搬送する
若しくは加熱炉に装入することにより、鋳片を加熱する
ための燃料を節約するのが狙いであり、鋳片温度の低下
は重大な問題である。However, in Japanese Unexamined Patent Publication No. 4-253505, when cooling the surface of the cast slab to a temperature not higher than the Ar1 point, no special cooling device is used and a normal secondary cooling device is used. It is used as it is, and the slab is strongly cooled by increasing the amount of cooling water. In addition to the fact that a slab with a large amount of unsolidified phase inside is difficult to cool, the cooling capacity of an ordinary secondary cooling device is not so strong even though the amount of cooling water is increased. Therefore, it is difficult to cool it to less than Ar1 point. Therefore, only the extremely thin part of the surface layer of the slab is cooled to the target temperature, the phase transformation is not sufficiently performed, and the effect of improving the surface flaw is insufficient. Or, when trying to cool to the target temperature, the cooling time becomes too long, the unsolidified phase decreases, and the subsequent heat recovery is insufficient to raise the temperature to the prescribed temperature. Not only will cracks occur and the energy saving effect will decrease,
Problems such as the HDR process itself becoming impossible occur. In the HDR process and the HCR process, it is aimed to save the fuel for heating the slab by transporting the slab after solidification / cooling to the hot rolling mill as high as possible or by charging it into the heating furnace. Therefore, the decrease of the slab temperature is a serious problem.
【０００８】本発明は上記事情に鑑みなされたもので、
その目的とするところは、鋳片表面を一旦Ａr1点以下の
温度まで冷却し、次いで、復熱等により鋳片温度を昇温
させてＨＤＲプロセスやＨＣＲプロセスにより鋼板を製
造する際に、急速に且つ確実に鋳片表面温度をＡr1点以
下まで冷却し、これらプロセスにより発生する特有の鋼
板表面疵を防止して表面性状に優れた鋼板の製造を可能
にすると同時に、省エネルギー効果が大きい高温鋳片を
得ることができる連続鋳造鋳片の直送圧延方法を提供す
ることである。The present invention has been made in view of the above circumstances.
The purpose is to cool the surface of the slab once to a temperature below the Ar1 point and then raise the slab temperature by recuperating heat to rapidly produce a steel sheet by the HDR process or HCR process. Moreover, the slab surface temperature is surely cooled to the Ar1 point or lower to prevent the peculiar steel plate surface defects generated by these processes to enable the production of a steel plate with excellent surface properties, and at the same time, a high-temperature slab with a large energy saving effect. The object of the present invention is to provide a method for directly feeding and rolling a continuously cast slab capable of obtaining the above.
【０００９】[0009]
【課題を解決するための手段】本発明者等は、上記課題
を解決するために鋭意検討を実施した、以下に検討結果
を説明する。Means for Solving the Problems The inventors of the present invention have made earnest studies to solve the above problems, and the results of the studies will be described below.
【００１０】鋳片の有する顕熱及び潜熱を無駄にロスさ
せないためには、必要最小量の冷却水を用いて鋳片を短
時間でＡr1点以下までに冷却し、次いで、鋳片の有する
顕熱及び潜熱で復熱させることが必要である。即ち、所
定時間以内で鋳片表面をＡr1点以下まで冷却するために
は、従来の二次冷却装置に比べて非常に大きな抜熱を行
う必要がある。In order to prevent wasteful loss of sensible heat and latent heat of the slab, the slab is cooled to the Ar1 point or less in a short time by using the necessary minimum amount of cooling water, and then the slab has the sensible heat. It is necessary to reheat with heat and latent heat. That is, in order to cool the surface of the cast slab to the Ar1 point or less within a predetermined time, it is necessary to remove heat much larger than that of the conventional secondary cooling device.
【００１１】そこで、本発明では急速冷却を実現するた
めに、強冷却を実施する範囲の鋳片の支持装置として、
通常の連続鋳造機の二次冷却帯で一般的に採用されてい
るロールに替わって、一部の連続鋳造機の鋳型直下で採
用されているグリッドを採用することとした。グリッド
形式にすることにより、スプレーノズルを密集して配置
することが可能になり、又、鋳片のバルジングを抑制す
ることができる。グリッドとは鋳鉄製等の板形状の金物
で、鋳造中の鋳片を面で支持するタイプの支持金物であ
る。そのため、線で支持するロールに比較して鋳片支持
面積が広くなると云う利点を有している。Therefore, in the present invention, in order to realize rapid cooling, as a supporting device for a cast piece in a range where strong cooling is carried out,
Instead of the rolls that are generally used in the secondary cooling zone of a normal continuous casting machine, we decided to use the grid that is used directly under the mold of some continuous casting machines. By adopting the grid type, it becomes possible to arrange the spray nozzles densely, and it is possible to suppress the bulging of the slab. The grid is a plate-shaped metal object made of cast iron or the like, and is a supporting metal object of a type that supports a slab being cast on a surface. Therefore, it has an advantage that the slab support area becomes larger than that of a roll supported by a wire.
【００１２】又、エアーミストスプレー方式の場合に
は、冷却水量に応じた大量のエアーが必要になるため、
本発明では冷却水のみを噴霧するスプレーノズルを用い
ることとした。スプレーノズルはフルコーン型とした。Further, in the case of the air mist spray system, a large amount of air corresponding to the amount of cooling water is required,
In the present invention, a spray nozzle that sprays only cooling water is used. The spray nozzle was a full cone type.
【００１３】図１に、本発明で用いた急速冷却装置の概
略図を示す。図１において、符号８はガイドロール、１
４は急速冷却装置、１５はプレゾーン、１６は第１ゾー
ン、１７は第２ゾーン、１８及び１８ａはグリッド、１
９はフルコーン型のスプレーノズルである。FIG. 1 shows a schematic view of the rapid cooling device used in the present invention. In FIG. 1, reference numeral 8 is a guide roll, 1
4 is a rapid cooling device, 15 is a pre-zone, 16 is a first zone, 17 is a second zone, 18 and 18a are grids, 1
Reference numeral 9 is a full cone type spray nozzle.
【００１４】図１に示すように、急速冷却装置１４は、
グリッドを設置せずにスプレーノズル１９のみを集中さ
せた第１ゾーン１６と、スプレーノズル１９とグリッド
１８，１８ａとを組み合わせた第２ゾーン１７とを備え
ている。第１ゾーン１６にスプレーノズル１９を集中配
置した理由は、短時間で鋳片表面を冷却し、第２ゾーン
１７での冷却能を確保するためである。即ち、第１ゾー
ン１６で鋳片表面を瞬時に或る温度以下まで冷却し、第
２ゾーン１７で冷却を継続することにより、鋳片表面に
おける伝熱形態を膜沸騰領域から核沸騰領域との遷移領
域に移行させることができ、高い冷却能を得ることがで
きる。尚、プレゾーン１５はグリッド１８とスプレーノ
ズル１９とが配置された構造であり、プレゾーン１５
は、本発明において必ずしも必要ではないが、ガイドロ
ール８から第１ゾーン１６に移行する領域での鋳片のバ
ルジングを防止する観点から設置することが好ましい。As shown in FIG. 1, the rapid cooling device 14 includes
A first zone 16 in which only the spray nozzles 19 are concentrated without installing a grid and a second zone 17 in which the spray nozzles 19 and the grids 18 and 18a are combined are provided. The reason why the spray nozzles 19 are centrally arranged in the first zone 16 is to cool the surface of the slab in a short time and to secure the cooling ability in the second zone 17. That is, the slab surface is instantly cooled to a certain temperature or less in the first zone 16 and the cooling is continued in the second zone 17, so that the heat transfer form on the slab surface is changed from the film boiling region to the nucleate boiling region. It is possible to shift to the transition region and obtain a high cooling capacity. The prezone 15 has a structure in which a grid 18 and a spray nozzle 19 are arranged.
Is not necessarily required in the present invention, but is preferably installed from the viewpoint of preventing bulging of the slab in the region where the guide roll 8 transitions to the first zone 16.
【００１５】鋳片表面の伝熱形態が遷移領域となるため
の条件は、鋳片表面温度の他に鋳片表面性状、冷却水の
水温、水圧、被冷却物（ここでは鋳片）の熱伝導率等に
も左右されるが、本発明で対象とする高温鋳片の場合、
鋳片表面温度を７００℃以下にすれば遷移領域に移行
し、鋳片の冷却能が向上する。図２に、鋳片表面温度と
伝熱形態及び熱伝達係数との関係を示す。第１ゾーン１
６で大量の冷却水を噴霧して鋳片表面温度を７００℃以
下にすることにより、同じ冷却水量を第１ゾーン１６及
び第２ゾーン１７で平均的に噴霧するよりも効率的に鋳
片を冷却することができる。平均的に噴霧した場合に
は、遷移領域に到達しないことがあるからである。The conditions under which the heat transfer form on the surface of the slab becomes the transition region are, in addition to the surface temperature of the slab, the surface properties of the slab, the water temperature of the cooling water, the water pressure, the heat of the object to be cooled (the slab here). Although it depends on the conductivity and the like, in the case of the high-temperature cast piece targeted by the present invention,
If the surface temperature of the slab is set to 700 ° C. or lower, it shifts to the transition region, and the cooling ability of the slab improves. FIG. 2 shows the relationship between the slab surface temperature, the heat transfer form and the heat transfer coefficient. First zone 1
By spraying a large amount of cooling water at 6 to control the surface temperature of the slab to 700 ° C. or less, the slab can be produced more efficiently than evenly spraying the same amount of cooling water in the first zone 16 and the second zone 17. Can be cooled. This is because the transition region may not be reached when spraying on average.
【００１６】第１ゾーン１６にはグリッドが配置されて
おらず鋳片を支持することができないため、第１ゾーン
１６の鋳造方向長さを３５０ｍｍ以下とした。第１ゾー
ン１６をこれ以上長くすると、溶鋼静圧によるバルジン
グの発生が懸念され、望ましくない。又、急速冷却後に
おける鋳片内部の未凝固相による復熱の期間を長くさせ
て鋳片を十分に復熱させるために、第２ゾーン１７の鋳
造方向長さは最大１５００ｍｍとした。一方、第２ゾー
ン１７の鋳造方向長さが５００ｍｍ未満では、鋳片を十
分に冷却することができないため５００ｍｍ以上とし
た。Since the grid is not arranged in the first zone 16 and the slab cannot be supported, the length of the first zone 16 in the casting direction is set to 350 mm or less. If the first zone 16 is made longer than this, bulging may occur due to the static pressure of molten steel, which is not desirable. Further, in order to lengthen the period of recuperation due to the unsolidified phase inside the slab after the rapid cooling to sufficiently recuperate the slab, the maximum length of the second zone 17 in the casting direction was 1500 mm. On the other hand, if the length of the second zone 17 in the casting direction is less than 500 mm, the slab cannot be cooled sufficiently, so the length is set to 500 mm or more.
【００１７】このような構成の急速冷却装置１４であっ
ても、鋳片表面をＡr1点以下まで冷却するに必要な冷却
水量は鋳片を冷却する時期により異なってくる。即ち、
鋳造初期には鋳片内部には多くの未凝固相があり、凝固
厚みも薄いことから大量の冷却水を必要とし、逆に、鋳
造末期には未凝固相が少なくなり、凝固厚みも厚いこと
から比較的少ない冷却水で冷却することができる。但
し、鋳造初期には鋳片内部に多くの未凝固相があり、急
速冷却後、未凝固相の有する顕熱及び潜熱により外部加
熱をしなくても鋳片を高温域まで復熱させることができ
ると云う利点があり、この利点は未凝固相が少なくなる
鋳造末期になるほど享受できなくなる。Even in the rapid cooling device 14 having such a structure, the amount of cooling water required to cool the surface of the cast slab to the Ar1 point or less differs depending on the timing of cooling the cast slab. That is,
At the beginning of casting, there are many unsolidified phases inside the slab, and the solidified thickness is thin, so a large amount of cooling water is required. Conversely, at the end of casting, the unsolidified phase is small and the solidified thickness is thick. Can be cooled with relatively little cooling water. However, there are many unsolidified phases inside the slab at the beginning of casting, and after rapid cooling, the slab can be reheated to a high temperature range without external heating due to sensible heat and latent heat of the unsolidified phase. There is an advantage that it can be done, and this advantage cannot be enjoyed until the final stage of casting when the amount of unsolidified phase decreases.
【００１８】そこで、急速冷却装置の設置位置を連続鋳
造機の鋳造方向で変化させると共に急速冷却装置におけ
る冷却水量を種々変化させ、鋳片の伝熱計算を実施し
た。この場合、連続鋳造機の矯正帯では急速冷却の実施
を適用しないようにした。鋳片表面に矯正応力が発生す
る矯正帯で鋳片表面温度を大きく変化させると、鋳片表
面に歪みが生じ、鋳片表面に割れを発生させる虞がある
ためである。湾曲型連続鋳造機では湾曲部から水平部に
かけて１回の矯正があり、垂直曲げ型の連続鋳造機で
は、垂直部から湾曲部（上部矯正）へ、又、湾曲部から
水平部（下部矯正）へと２回の矯正がある。Therefore, the installation position of the rapid cooling device was changed in the casting direction of the continuous casting machine and the amount of cooling water in the rapid cooling device was variously changed, and the heat transfer calculation of the slab was carried out. In this case, rapid cooling was not applied in the straightening zone of the continuous casting machine. This is because if the slab surface temperature is greatly changed in a straightening band where straightening stress is generated on the slab surface, distortion may occur on the slab surface and cracks may occur on the slab surface. In a curved type continuous casting machine, there is one correction from the curved portion to the horizontal portion. In a vertical bending type continuous casting machine, from the vertical portion to the curved portion (upper straightening) and from the curved portion to the horizontal portion (lower straightening). There are two corrections.
【００１９】伝熱計算の結果、鋳片表面をＡr1点以下ま
で冷却するに必要な冷却水量は、急速冷却装置の設置位
置即ち鋳片の凝固状態により、３つの条件に大別できる
ことが判明した。即ち、湾曲型連続鋳造機の場合には、
：鋳型直下を開始点として鋳型内溶鋼湯面から鋳造方
向８ｍの位置までの範囲に急速冷却装置を設置した場
合、：鋳型内溶鋼湯面から鋳造方向８ｍの位置を開始
点として矯正帯開始位置までの範囲に急速冷却装置を設
置した場合、：矯正帯終了位置を開始点として鋳片切
断位置までの範囲に急速冷却装置を設置した場合の３つ
の条件であり、垂直曲げ型の連続鋳造機の場合には、
：上部矯正帯終了点を開始点として上部矯正帯から鋳
造方向４ｍの位置までの範囲に急速冷却装置を設置した
場合、：上部矯正帯から鋳造方向４ｍの位置を開始点
として下部矯正帯開始位置までの範囲に急速冷却装置を
設置した場合、：下部矯正帯終了位置を開始点として
鋳片切断位置までの範囲に急速冷却装置を設置した場合
の３つの条件である。As a result of heat transfer calculation, it has been found that the amount of cooling water required for cooling the surface of the slab to the Ar1 point or less can be roughly classified into three conditions depending on the installation position of the rapid cooling device, that is, the solidification state of the slab. . That is, in the case of a curved continuous casting machine,
: When the rapid cooling device is installed in the range from the molten steel surface in the mold to the position of 8 m in the casting direction with the position immediately below the mold as the starting point :: The straightening band start position with the position of 8 m in the casting direction from the molten steel surface in the mold as the starting point If the rapid cooling device is installed in the range up to :, there are three conditions when the rapid cooling device is installed in the range from the end position of the straightening zone to the cutting position of the ingot, and the vertical bending type continuous casting machine. In Case of,
: If the rapid cooling device is installed in the range from the upper straightening strip to the position of 4 m in the casting direction with the end point of the upper straightening strip as the starting point :: Start position of the lower straightening strip with the position of 4 m from the upper straightening strip as the starting point When the rapid cooling device is installed in the range up to: The three conditions are: when the rapid cooling device is installed in the range from the end position of the lower straightening zone to the cutting position of the slab.
【００２０】第１の条件である、湾曲型連続鋳造機では
鋳型直下を開始点として鋳型内溶鋼湯面から鋳造方向８
ｍ位置までの範囲、及び、垂直曲げ型連続鋳造機では上
部矯正帯終了点を開始点として上部矯正帯から鋳造方向
４ｍ位置までの範囲で鋳片表面をＡr1点以下まで冷却す
る場合、この条件に基づいた伝熱計算の結果から、厚み
が２００ｍｍ〜３００ｍｍの鋳片を最大３．０ｍ／ｍｉ
ｎの鋳片引き抜き速度で鋳造する場合において、第１ゾ
ーンで鋳片表面温度を７００℃以下まで低下させるに
は、第１ゾーンの水量密度は３０００ｌ／ｍｉｎ・ｍ2
以上必要であり、又、第２ゾーンで鋳片表面温度をＡr1
点以下に保つためには、第２ゾーンの水量密度は１００
０ｌ／ｍｉｎ・ｍ2 以上必要であることが分かった。In the curved continuous casting machine, which is the first condition, the casting direction 8 is set from the molten steel level in the casting mold starting from just below the casting mold.
When cooling the surface of the slab to the Ar1 point or less in the range up to m position, and in the vertical bending type continuous casting machine, from the end point of the upper straightening band to the starting point in the range from the upper straightening band to the 4m position in the casting direction, this condition From the result of the heat transfer calculation based on, the maximum thickness of the cast slab having a thickness of 200 mm to 300 mm is 3.0 m / mi.
When casting at a slab drawing speed of n, in order to lower the slab surface temperature to 700 ° C. or lower in the first zone, the water volume density in the first zone is 3000 l / min · m 2
The above is required, and the surface temperature of the slab in the second zone is Ar1.
In order to keep below the point, the water volume density in the second zone is 100
It was found that 0 l / min · m 2 or more is required.
【００２１】第２の条件である、湾曲型連続鋳造機では
鋳型内溶鋼湯面から鋳造方向８ｍの位置を開始点として
矯正帯開始位置までの範囲、及び、垂直曲げ型連続鋳造
機では上部矯正帯終了位置から鋳造方向４ｍの位置を開
始点として下部矯正帯開始位置までの範囲で鋳片表面を
Ａr1点以下まで冷却する場合、この条件に基づいた伝熱
計算の結果から、厚みが２００ｍｍ〜３００ｍｍの鋳片
を最大３．０ｍ／ｍｉｎの鋳片引き抜き速度で鋳造する
場合において、第１ゾーンで鋳片表面温度を７００℃以
下まで低下させるには、第１ゾーンの水量密度は２００
０ｌ／ｍｉｎ・ｍ2 以上必要であり、又、第２ゾーンで
鋳片表面温度をＡr1点以下に保つためには、第２ゾーン
の水量密度は８００ｌ／ｍｉｎ・ｍ2 以上必要であるこ
とが分かった。The second condition is that in the curved continuous casting machine, the range from the molten steel surface in the mold to the straightening zone start position starting from the position of 8 m in the casting direction, and in the vertical bending continuous casting machine the upper straightening When the surface of the slab is cooled to the Ar1 point or less within the range from the end position of the strip to the start position of the lower straightening strip with the position of 4 m in the casting direction as the start point, the thickness of 200 mm to When casting a 300 mm slab at a slab drawing speed of 3.0 m / min at the maximum, in order to lower the slab surface temperature to 700 ° C. or less in the first zone, the water amount density in the first zone is 200
0 l / min · m 2 or more is required, and in order to keep the slab surface temperature at the Ar 1 point or lower in the second zone, the water amount density in the second zone must be 800 l / min · m 2 or more. Do you get it.
【００２２】第３の条件である、湾曲型連続鋳造機では
矯正帯終了位置を開始点として鋳片切断位置までの範
囲、及び、垂直曲げ型連続鋳造機では下部矯正帯終了位
置を開始点として鋳片切断位置までの範囲で鋳片表面を
Ａr1点以下まで冷却する場合、この条件に基づいた伝熱
計算の結果から、厚みが２００ｍｍ〜３００ｍｍの鋳片
を最大３．０ｍ／ｍｉｎの鋳片引き抜き速度で鋳造する
場合において、第１ゾーンで鋳片表面温度を７００℃以
下まで低下させるには、第１ゾーンの水量密度は１５０
０ｌ／ｍｉｎ・ｍ2 以上必要であり、又、第２ゾーンで
鋳片表面温度をＡr1点以下に保つためには、第２ゾーン
の水量密度は５００ｌ／ｍｉｎ・ｍ2 以上必要であるこ
とが分かった。In the third condition, in the curved continuous casting machine, the range from the straightening band end position to the slab cutting position is the starting point, and in the vertical bending continuous casting machine, the lower straightening band end position is the starting point. When cooling the surface of the slab to the Ar1 point or less within the range up to the cutting position of the slab, from the results of heat transfer calculation based on this condition, a slab with a thickness of 200 mm to 300 mm can be cast with a maximum of 3.0 m / min. In the case of casting at the drawing speed, in order to lower the slab surface temperature to 700 ° C. or lower in the first zone, the water amount density in the first zone is 150.
0l / min · m requires 2 or more, also be to keep the billet surface temperature below Ar1 point in the second zone, water density of the second zone is required 500 l / min · m 2 or more Do you get it.
【００２３】尚、垂直曲げ型連続鋳造機において、上部
矯正帯開始までに急速冷却を実施しない理由は、鋳型直
下と上部矯正帯開始位置までの距離が短く、上記の急速
冷却装置を用いてもＡr1点以下まで冷却できない場合
や、鋳片の復熱が間に合わずにＡr1点以下の状態で矯正
される場合の表面疵の発生が懸念されるためである。
又、湾曲型連続鋳造機の鋳型内溶鋼湯面から鋳造方向８
ｍ位置までの範囲、及び、垂直曲げ型連続鋳造機の上部
矯正帯から鋳造方向４ｍ位置までの範囲は、通常の連続
鋳造機の場合には下部矯正帯を十分外れる範囲である。In the vertical bending type continuous casting machine, the reason why the rapid cooling is not performed before the start of the upper straightening band is that the distance between the position immediately below the mold and the start position of the upper straightening band is short, and the above rapid cooling device is used. This is because there is a concern that surface defects may occur when it cannot be cooled down to the Ar1 point or lower, or when the slab is straightened in a state where the reheat of the cast piece is under the Ar1 point or lower.
In addition, the casting direction 8 from the molten steel surface in the mold of the curved continuous casting machine
The range up to the m position and the range from the upper straightening band of the vertical bending type continuous casting machine to the position of 4 m in the casting direction are ranges that are sufficiently out of the lower straightening band in the case of a normal continuous casting machine.
【００２４】本発明は上記検討結果に基づきなされたも
ので、第１の発明による連続鋳造鋳片の直送圧延方法
は、鋳片表面の伝熱形態が核沸騰と膜沸騰との遷移領域
になるように調整した冷却装置を用いて鋳片をその表面
温度がＡr1点以下になるまで冷却し、その後、冷却強度
の調整若しくは断熱や加熱を施して鋳片表面温度をＡc3
点以上に昇温し、鋳片表面温度をＡc3点以上に保持した
まま熱間圧延機まで搬送して、熱間圧延することを特徴
とするものである。The present invention has been made based on the above-mentioned examination results. In the method for directly feeding and rolling a continuously cast slab according to the first invention, the heat transfer form on the surface of the slab becomes a transition region between nucleate boiling and film boiling. Cool the slab using a cooling device adjusted as described above until the surface temperature falls below the Ar1 point, and then adjust the cooling strength or perform heat insulation or heating to adjust the slab surface temperature to Ac3.
It is characterized in that the temperature of the slab is raised to a point or higher, the slab surface temperature is maintained at an Ac3 point or higher, and the slab is conveyed to a hot rolling mill for hot rolling.
【００２５】第２の発明による連続鋳造鋳片の直送圧延
方法は、鋳片表面の伝熱形態が核沸騰と膜沸騰との遷移
領域になるように調整した冷却装置を用いて鋳片をその
表面温度がＡr1点以下になるまで冷却し、その後、冷却
強度の調整若しくは断熱や加熱を施して鋳片表面温度を
Ａc3点以上に昇温し、鋳片表面温度をＡc3点以上に保持
したまま加熱炉まで搬送し、加熱炉で加熱した後に熱間
圧延することを特徴とするものである。In the method for directly feeding and rolling continuously cast slabs according to the second aspect of the present invention, the slabs are cast by using a cooling device adjusted so that the heat transfer form on the surface of the slab is in the transition region between nucleate boiling and film boiling. Cool until the surface temperature falls to or below the Ar1 point, then adjust the cooling strength or perform heat insulation or heating to raise the slab surface temperature to the Ac3 point or higher, and keep the slab surface temperature at the Ac3 point or higher. It is characterized in that it is conveyed to a heating furnace, heated in the heating furnace, and then hot-rolled.
【００２６】第３の発明による連続鋳造鋳片の直送圧延
方法は、第１の発明又は第２の発明において、湾曲型連
続鋳造機の鋳型直下を開始点として鋳型内溶鋼湯面から
鋳造方向８ｍの位置までの範囲に、鋳造方向の長さが３
５０ｍｍ以下であり、冷却水量密度が３０００ｌ／ｍｉ
ｎ・ｍ2 以上であるスプレーノズルが配置された第１ゾ
ーンと、鋳造方向の長さが５００ｍｍ〜１５００ｍｍで
あり、冷却水量密度が１０００ｌ／ｍｉｎ・ｍ2 以上で
あるスプレーノズルと鋳片を支持するグリッドとが配置
された第２ゾーンとを具備する急速冷却装置を設置し、
第１ゾーンで鋳片表面温度を７００℃以下に冷却して急
速冷却装置における鋳片表面の伝熱形態を核沸騰と膜沸
騰との遷移領域に調整し、この急速冷却装置により鋳片
をその表面温度がＡr1点以下になるまで冷却することを
特徴とするものである。A method for directly feeding and rolling continuously cast slabs according to a third aspect of the invention is that in the first or second aspect of the invention, the casting direction is 8 m from the surface of the molten steel in the casting mold starting from immediately below the casting mold of the curved continuous casting machine. The length in the casting direction is 3 up to the position
50 mm or less, cooling water density is 3000 l / mi
Supports the first zone in which the spray nozzle of n · m 2 or more is arranged, the length in the casting direction of 500 mm to 1500 mm, and the spray nozzle and the slab of cooling water density of 1000 l / min · m 2 or more. And a second zone in which a grid for
In the first zone, the slab surface temperature is cooled to 700 ° C. or lower to adjust the heat transfer form of the slab surface in the rapid cooling device to a transition region between nucleate boiling and film boiling, and the slab is cooled by the rapid cooling device. It is characterized in that it is cooled until the surface temperature falls below the Ar1 point.
【００２７】第４の発明による連続鋳造鋳片の直送圧延
方法は、第１の発明又は第２の発明において、垂直曲げ
型連続鋳造機の上部矯正帯終了位置を開始点として上部
矯正帯終了位置から鋳造方向４ｍの位置までの範囲に、
鋳造方向の長さが３５０ｍｍ以下であり、冷却水量密度
が３０００ｌ／ｍｉｎ・ｍ2 以上であるスプレーノズル
が配置された第１ゾーンと、鋳造方向の長さが５００ｍ
ｍ〜１５００ｍｍであり、冷却水量密度が１０００ｌ／
ｍｉｎ・ｍ2 以上であるスプレーノズルと鋳片を支持す
るグリッドとが配置された第２ゾーンとを具備する急速
冷却装置を設置し、第１ゾーンで鋳片表面温度を７００
℃以下に冷却して急速冷却装置における鋳片表面の伝熱
形態を核沸騰と膜沸騰との遷移領域に調整し、この急速
冷却装置により鋳片をその表面温度がＡr1点以下になる
まで冷却することを特徴とするものである。The method for directly feeding and rolling continuously cast slabs according to a fourth aspect of the present invention is the method for directly feeding and rolling continuously cast slabs according to the first or second aspect, wherein the upper straightening strip end position of the vertical bending type continuous casting machine is set as a starting point. To the position of 4 m in the casting direction,
A first zone in which a spray nozzle having a length in the casting direction of 350 mm or less and a cooling water amount density of 3000 l / min · m 2 or more is arranged, and a length in the casting direction of 500 m
m-1500 mm, cooling water density is 1000 l /
A rapid cooling device having a second zone in which a spray nozzle having a diameter of min · m 2 or more and a grid supporting the slab is arranged is installed, and the slab surface temperature is 700 in the first zone.
After cooling to below ℃, adjust the heat transfer form on the surface of the cast in the rapid cooling device to the transition region between nucleate boiling and film boiling, and cool the cast by the rapid cooling device until the surface temperature becomes below Ar1 point. It is characterized by doing.
【００２８】第５の発明による連続鋳造鋳片の直送圧延
方法は、第１の発明又は第２の発明において、湾曲型連
続鋳造機の鋳型内溶鋼湯面から鋳造方向８ｍの位置を開
始点として矯正帯開始位置までの範囲に、鋳造方向の長
さが３５０ｍｍ以下であり、冷却水量密度が２０００ｌ
／ｍｉｎ・ｍ2 以上であるスプレーノズルが配置された
第１ゾーンと、鋳造方向の長さが５００ｍｍ〜１５００
ｍｍであり、冷却水量密度が８００ｌ／ｍｉｎ・ｍ2 以
上であるスプレーノズルと鋳片を支持するグリッドとが
配置された第２ゾーンとを具備する急速冷却装置を設置
し、第１ゾーンで鋳片表面温度を７００℃以下に冷却し
て急速冷却装置における鋳片表面の伝熱形態を核沸騰と
膜沸騰との遷移領域に調整し、この急速冷却装置により
鋳片をその表面温度がＡr1点以下になるまで冷却するこ
とを特徴とするものである。The method for directly feeding and rolling continuously cast slabs according to the fifth aspect of the present invention is the method of the first or second aspect of the invention, wherein the starting point is a position 8 m from the molten steel surface in the mold of the curved continuous casting machine. Within the range up to the straightening zone start position, the length in the casting direction is 350 mm or less, and the cooling water volume density is 2000 l.
/ Min · m 2 or more, the first zone where the spray nozzle is arranged, and the length in the casting direction is 500 mm to 1500
mm, and a rapid cooling device equipped with a second zone in which a spray nozzle having a cooling water volume density of 800 l / min · m 2 or more and a grid supporting a cast piece is arranged, and casting is performed in the first zone. The surface temperature of the cast piece in the rapid cooling device is adjusted to a transition region between nucleate boiling and film boiling by cooling the surface temperature of the casting piece to 700 ° C or less, and the surface temperature of the cast piece is Ar1 point by this rapid cooling device. It is characterized by cooling to the following.
【００２９】第６の発明による連続鋳造鋳片の直送圧延
方法は、第１の発明又は第２の発明において、垂直曲げ
型連続鋳造機の上部矯正帯終了位置から鋳造方向４ｍの
位置を開始点として下部矯正帯開始位置までの範囲に、
鋳造方向の長さが３５０ｍｍ以下であり、冷却水量密度
が２０００ｌ／ｍｉｎ・ｍ2 以上であるスプレーノズル
が配置された第１ゾーンと、鋳造方向の長さが５００ｍ
ｍ〜１５００ｍｍであり、冷却水量密度が８００ｌ／ｍ
ｉｎ・ｍ2 以上であるスプレーノズルと鋳片を支持する
グリッドとが配置された第２ゾーンとを具備する急速冷
却装置を設置し、第１ゾーンで鋳片表面温度を７００℃
以下に冷却して急速冷却装置における鋳片表面の伝熱形
態を核沸騰と膜沸騰との遷移領域に調整し、この急速冷
却装置により鋳片をその表面温度がＡr1点以下になるま
で冷却することを特徴とするものである。In the method for directly feeding and rolling continuously cast slabs according to the sixth aspect of the invention, in the first or second aspect of the invention, the starting point is a position 4 m from the upper straightening strip end position of the vertical bending type continuous casting machine in the casting direction. As a range up to the lower correction band start position,
A first zone in which a spray nozzle having a length in the casting direction of 350 mm or less and a cooling water amount density of 2000 l / min · m 2 or more is arranged, and a length in the casting direction of 500 m
m-1500 mm, cooling water volume density is 800 l / m
A quick cooling device having a second zone in which a spray nozzle having a diameter of at least m 2 and a grid supporting the slab is arranged is installed, and the slab surface temperature is 700 ° C. in the first zone.
By cooling to the following, the heat transfer form on the surface of the slab in the rapid cooling device is adjusted to the transition region between nucleate boiling and film boiling, and the slab is cooled by this rapid cooling device until the surface temperature becomes below the Ar1 point. It is characterized by that.
【００３０】第７の発明による連続鋳造鋳片の直送圧延
方法は、第１の発明又は第２の発明において、湾曲型連
続鋳造機の矯正帯終了位置を開始点として鋳片切断位置
までの範囲に、鋳造方向の長さが３５０ｍｍ以下であ
り、冷却水量密度が１５００ｌ／ｍｉｎ・ｍ2 以上であ
るスプレーノズルが配置された第１ゾーンと、鋳造方向
の長さが５００ｍｍ〜１５００ｍｍであり、冷却水量密
度が５００ｌ／ｍｉｎ・ｍ2 以上であるスプレーノズル
と鋳片を支持するグリッドとが配置された第２ゾーンと
を具備する急速冷却装置を設置し、第１ゾーンで鋳片表
面温度を７００℃以下に冷却して急速冷却装置における
鋳片表面の伝熱形態を核沸騰と膜沸騰との遷移領域に調
整し、この急速冷却装置により鋳片をその表面温度がＡ
r1点以下になるまで冷却することを特徴とするものであ
る。A method for directly feeding and rolling continuously cast slabs according to a seventh aspect is the range from the first or second aspect of the invention to the slab cutting position with the straightening zone end position of the curved continuous casting machine as a starting point. A first zone in which a spray nozzle having a length in the casting direction of 350 mm or less and a cooling water amount density of 1500 l / min · m 2 or more is disposed, and a length in the casting direction of 500 mm to 1500 mm, and cooling A rapid cooling device comprising a second zone in which a spray nozzle having a water amount density of 500 l / min · m 2 or more and a grid supporting the slab is arranged is installed, and the slab surface temperature is 700 in the first zone. The surface of the slab is cooled to a temperature below A by adjusting the heat transfer form on the surface of the slab in the rapid cooling device to a transition region between nucleate boiling and film boiling.
It is characterized by cooling until it reaches the r1 point or less.
【００３１】第８の発明による連続鋳造鋳片の直送圧延
方法は、第１の発明又は第２の発明において、垂直曲げ
型連続鋳造機の下部矯正帯終了位置を開始点として鋳片
切断位置までの範囲に、鋳造方向の長さが３５０ｍｍ以
下であり、冷却水量密度が１５００ｌ／ｍｉｎ・ｍ2 以
上であるスプレーノズルが配置された第１ゾーンと、鋳
造方向の長さが５００ｍｍ〜１５００ｍｍであり、冷却
水量密度が５００ｌ／ｍｉｎ・ｍ2 以上であるスプレー
ノズルと鋳片を支持するグリッドとが配置された第２ゾ
ーンとを具備する急速冷却装置を設置し、第１ゾーンで
鋳片表面温度を７００℃以下に冷却して急速冷却装置に
おける鋳片表面の伝熱形態を核沸騰と膜沸騰との遷移領
域に調整し、この急速冷却装置により鋳片をその表面温
度がＡr1点以下になるまで冷却することを特徴とするも
のである。According to an eighth aspect of the present invention, there is provided a method for directly feeding and rolling continuously cast slabs according to the first or second aspect of the invention, wherein the end position of the lower straightening band of the vertical bending type continuous casting machine is used as a starting point to the slab cutting position. In the range of 1, the length in the casting direction is 350 mm or less, the first zone in which the spray nozzle having the cooling water amount density of 1500 l / min · m 2 or more is arranged, and the length in the casting direction is 500 mm to 1500 mm. , A rapid cooling device equipped with a second zone in which a spray nozzle having a cooling water amount density of 500 l / min · m 2 or more and a grid supporting the slab is arranged, and the slab surface temperature in the first zone Is cooled to 700 ° C. or less to adjust the heat transfer form on the surface of the cast piece in the rapid cooling device to a transition region between nucleate boiling and film boiling, and the rapid cooling device lowers the surface temperature of the cast piece to the Ar1 point or less. It is characterized in that cooling to.
【００３２】[0032]
【発明の実施の形態】以下、添付図面を参照して本発明
の実施の形態を説明する。図３は、本発明の実施の形態
を示す図であって、急速冷却装置を備えた垂直曲げ型ス
ラブ連続鋳造機の側面概略図である。BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 3 is a view showing an embodiment of the present invention and is a schematic side view of a vertical bending slab continuous casting machine equipped with a rapid cooling device.
【００３３】図３に示すように、垂直曲げ型スラブ連続
鋳造機１は、溶鋼を注入して凝固させるための鋳型６
と、対向する一対のロールを１組としてそれぞれ複数組
のサポートロール７、ガイドロール８、ピンチロール９
からなる、鋳片２を支持するための鋳片支持ロールと、
鋳造された鋳片２を搬送するための複数本の搬送ロール
１１と、搬送ロール１１の上方に位置して鋳片２の引き
抜き速度と同調するガス切断機１０とを備えている。こ
れらの鋳片支持ロールには鋳片２を冷却するための二次
冷却装置（図示せず）が配置されている。ピンチロール
９は鋳片２の引き抜きを駆動するためのロールである。As shown in FIG. 3, the vertical bending type slab continuous casting machine 1 includes a mold 6 for injecting and solidifying molten steel.
And a plurality of sets of support rolls 7, guide rolls 8 and pinch rolls 9 each having a pair of opposing rolls as one set
And a slab support roll for supporting the slab 2,
A plurality of transport rolls 11 for transporting the cast slab 2 and a gas cutting machine 10 located above the transport roll 11 and synchronized with the drawing speed of the slab 2 are provided. A secondary cooling device (not shown) for cooling the slab 2 is arranged on these slab support rolls. The pinch roll 9 is a roll for driving pulling out of the slab 2.
【００３４】鋳片支持ロールの配列は、鋳型６直下の垂
直部と、垂直部につながる湾曲部と、湾曲部につながる
水平部の３つに分別され、垂直部から湾曲部への間に上
部矯正帯１２が設置され、湾曲部から水平部への間に下
部矯正帯１３が設置されている。図では上部矯正帯１２
及び下部矯正帯１３ともに複数対の鋳片支持ロールに渡
って矯正帯が設置されているが、一対の鋳片支持ロール
で行っても良い。鋳型６から引き抜かれた鋳片２は上部
矯正帯１２で曲げられ、更に下部矯正帯１３で曲げ戻さ
れて鋳造される。The arrangement of the slab supporting rolls is divided into three parts, namely, a vertical part immediately below the mold 6, a curved part connected to the vertical part, and a horizontal part connected to the curved part, and an upper part is arranged between the vertical part and the curved part. A straightening band 12 is installed, and a lower straightening band 13 is installed between the curved portion and the horizontal portion. In the figure, the upper straightening belt 12
Although the straightening strips are installed over a plurality of pairs of slab support rolls in both the lower straightening strip 13 and the lower straightening strip 13, they may be formed by a pair of slab support rolls. The slab 2 pulled out from the mold 6 is bent by the upper straightening strip 12 and further bent back by the lower straightening strip 13 to be cast.
【００３５】尚、湾曲型スラブ連続鋳造機の場合には、
鋳型の内面自体が湾曲しており、鋳型を含む湾曲部と、
この湾曲部につながる水平部の２つに分別され、図３に
示す下部矯正帯１３の位置が湾曲した鋳片を水平に矯正
する矯正帯となる。即ち、湾曲型スラブ連続鋳造機で
は、図３に示す上部矯正帯１２が設置されておらず、鋳
型から湾曲部が開始されるが、その他の部分は図３に示
す垂直曲げ型スラブ連続鋳造機１と同一であるため、こ
こではその説明は省略する。便宜上、図３に示す下部矯
正帯１３は湾曲型スラブ連続鋳造機の矯正帯をも意味す
ることとする。In the case of a curved type slab continuous casting machine,
The inner surface of the mold itself is curved, and a curved portion including the mold,
The lower straightening band 13 shown in FIG. 3, which is divided into two horizontal parts connected to the curved part, is a straightening band for straightening a curved slab. That is, in the curved slab continuous casting machine, the upper straightening band 12 shown in FIG. 3 is not installed, and the curved portion starts from the mold, but the other portions are the vertical bending slab continuous casting machine shown in FIG. Since it is the same as 1, the description thereof will be omitted here. For the sake of convenience, the lower straightening band 13 shown in FIG. 3 also means a straightening band of a curved slab continuous casting machine.
【００３６】鋳片表面をＡr1点以下まで冷却するための
急速冷却装置１４がガイドロール８，８の間に設置され
ている。図３では、急速冷却装置１４が上部矯正帯１２
の鋳造方向直下に設置されているが、急速冷却装置１４
の設置位置は図３に示す位置に限るわけではなく、垂直
曲げ型のスラブ連続鋳造機１の場合には、下部矯正帯１
３の範囲を除いた、上部矯正帯１２を越えた以降から鋳
片切断位置までの範囲の任意の位置に設置することがで
き、又、湾曲型スラブ連続鋳造機の場合には、矯正帯１
３を除いた、鋳型直下以降から鋳片切断位置までの範囲
の任意の位置に設置することができる。但し、前述した
ように、未凝固相４の有する顕熱及び潜熱により鋳片２
を迅速に且つ高温度に復熱させるには、急速冷却装置１
４を鋳型６に近い範囲に設置することが好ましい。A rapid cooling device 14 for cooling the surface of the slab to the Ar1 point or less is installed between the guide rolls 8, 8. In FIG. 3, the rapid cooling device 14 shows the upper straightening band 12
It is installed just below the casting direction of the
The installation position is not limited to the position shown in FIG. 3, but in the case of the vertical bending type slab continuous casting machine 1, the lower straightening strip 1
It can be installed at any position within the range from the point beyond the upper straightening strip 12 to the slab cutting position except the range of No. 3, and in the case of a curved slab continuous casting machine, the straightening strip 1
It can be installed at any position within the range from immediately below the mold to the cutting position of the cast, except for 3. However, as described above, due to the sensible heat and latent heat of the unsolidified phase 4, the cast piece 2
In order to quickly and reheat the air to a high temperature, the rapid cooling device 1
It is preferable to install 4 in a range close to the mold 6.
【００３７】この急速冷却装置１４は、前述した図１に
示すように、鋳造方向の上部側からプレゾーン１５、第
１ゾーン１６、及び第２ゾーン１７の３つのゾーンから
構成されている。プレゾーン１５には、グリッド１８
と、このグリッド１８の間隙に設置されたフルコーン型
スプレーノズル１９とが配置され、第１ゾーン１６に
は、グリッドは配置されずにフルコーン型スプレーノズ
ル１９のみが配置されている。第２ゾーン１７には、グ
リッド１８及びグリッド１８ａの２種類のグリッドが、
鋳片２が鋳片幅方向で必ず支持されるように鋳造方向で
交互に配置され、これらグッリド１８，１８ａの間隙に
はフルコーン型スプレーノズル１９が配置されている。
図１では、急速冷却装置１４をガイドロール８，８の間
に設置しているが、ピンチロール９とガイドロール８と
の間に設置しても良い。As shown in FIG. 1, the rapid cooling device 14 is composed of three zones, namely a pre-zone 15, a first zone 16 and a second zone 17 from the upper side in the casting direction. Grid 18 in the pre-zone 15
And a full-cone type spray nozzle 19 installed in the gap between the grids 18, and no grid is arranged in the first zone 16 and only the full-cone spray nozzle 19 is arranged. In the second zone 17, two types of grids, grid 18 and grid 18a,
The slabs 2 are alternately arranged in the casting direction so that the slabs 2 are always supported in the slab width direction, and a full-cone type spray nozzle 19 is arranged in the gap between the glide 18, 18a.
Although the rapid cooling device 14 is installed between the guide rolls 8 and 8 in FIG. 1, it may be installed between the pinch roll 9 and the guide roll 8.
【００３８】前述したように、第１ゾーン１６はその鋳
造方向長さを３５０ｍｍ以下とし、又、第２ゾーン１７
はその鋳造方向長さを５００ｍｍ〜１５００ｍｍとす
る。各ゾーンの冷却水量密度は、急速冷却装置１４が設
置される位置により以下のように規定する。As described above, the first zone 16 has a length in the casting direction of 350 mm or less, and the second zone 17
Has a casting direction length of 500 mm to 1500 mm. The cooling water amount density of each zone is defined as follows depending on the position where the quick cooling device 14 is installed.
【００３９】即ち、垂直曲げ型スラブ連続鋳造機１の場
合、急速冷却装置１４が上部矯正帯１２の終了点を開
始点として上部矯正帯１２から鋳造方向４ｍの位置まで
の範囲に設置される場合には、第１ゾーンの冷却水量密
度を３０００ｌ／ｍｉｎ・ｍ 2 以上、第２ゾーンの水量
密度を１０００ｌ／ｍｉｎ・ｍ2 以上とし、急速冷却
装置１４が上部矯正帯１２の終了位置から鋳造方向４ｍ
の位置を開始点として下部矯正帯１３の開始位置までの
範囲に設置される場合には、第１ゾーンの冷却水量密度
を２０００ｌ／ｍｉｎ・ｍ2 以上、第２ゾーンの水量密
度を８００ｌ／ｍｉｎ・ｍ2 以上とし、急速冷却装置
１４が下部矯正帯１３の終了点を開始点として鋳片切断
位置までの範囲に設置される場合には、第１ゾーンの冷
却水量密度を１５００ｌ／ｍｉｎ・ｍ2 以上、第２ゾー
ンの水量密度を５００ｌ／ｍｉｎ・ｍ2 以上とする。That is, in the case of the vertical bending type slab continuous casting machine 1,
If so, the rapid cooling device 14 opens the end point of the upper straightening band 12.
As a starting point from the upper straightening belt 12 to the position 4 m in the casting direction
When installed in the range of
Degree of 3000 l / min ・ m 2 Above, the amount of water in the second zone
Density 1000 l / min · m2 More than that, rapid cooling
The device 14 moves from the end position of the upper straightening belt 12 to the casting direction 4 m.
Starting from the position of
When installed in the range, the cooling water volume density of the first zone
2000 l / min · m2 Above, water density of the second zone
800 l / min ・ m2 Above, quick cooling device
14 cuts the slab starting from the end point of the lower straightening strip 13
If it is installed in the area up to the
Rejected water density of 1500 l / min · m2 Above, the second zo
Water density of 500 l / min ・ m2 That is all.
【００４０】又、湾曲型スラブ連続鋳造機の場合、急
速冷却装置１４が鋳型直下を開始点として鋳型内の溶鋼
湯面５から鋳造方向８ｍ位置までの範囲に設置される場
合には、第１ゾーンの冷却水量密度を３０００ｌ／ｍｉ
ｎ・ｍ2 以上、第２ゾーンの水量密度を１０００ｌ／ｍ
ｉｎ・ｍ2 以上とし、急速冷却装置１４が鋳型内溶鋼
湯面５から鋳造方向８ｍの位置を開始点として矯正帯１
３の開始位置までの範囲に設置される場合には、第１ゾ
ーンの冷却水量密度を２０００ｌ／ｍｉｎ・ｍ 2 以上、
第２ゾーンの水量密度を８００ｌ／ｍｉｎ・ｍ2 以上と
し、急速冷却装置１４が矯正帯１３の終了点を開始点
として鋳片切断位置までの範囲に設置される場合には、
第１ゾーンの冷却水量密度を１５００ｌ／ｍｉｎ・ｍ2
以上、第２ゾーンの水量密度を５００ｌ／ｍｉｎ・ｍ2
以上とする。In the case of a curved type slab continuous casting machine, the
The rapid cooling device 14 starts the molten steel in the mold immediately below the mold.
When installed in the range from the molten metal 5 to the casting direction 8m
In this case, set the cooling water volume density in the first zone to 3000 l / mi.
nm2 As described above, the water volume density in the second zone is 1000 l / m
in ・ m2 As described above, the rapid cooling device 14 is the molten steel in the mold.
Straightening band 1 starting from a position 8 m from the molten metal surface 5 in the casting direction
When installed in the range up to the start position of 3,
The cooling water volume density of the furnace is 2000 l / min.m 2 that's all,
The water density in the second zone is 800 l / min.m2 And above
Then, the rapid cooling device 14 starts the end point of the straightening band 13 at the start point.
When installed in the range up to the slab cutting position as
The cooling water volume density in the first zone is 1500 l / min · m2
As described above, the water volume density in the second zone is 500 l / min · m2
That is all.
【００４１】プレゾーン１５は、本発明において必ずし
も必要ではないが、ガイドロール８から直ちに第１ゾー
ン１６に移行する場合には、鋳片２が支持されない間隔
が長くなり、バルジング発生の懸念があるが、プレゾー
ン１５を設置することによりり、鋳片２の支持を確保す
ることができる。プレゾーン１５の鋳造方向長さは５０
ｍｍ〜２５０ｍｍで十分である。The pre-zone 15 is not always necessary in the present invention, but when the guide roll 8 is immediately moved to the first zone 16, the interval at which the slab 2 is not supported becomes long and there is a concern that bulging may occur. By installing the pre-zone 15, it is possible to secure the support of the slab 2. The length of the prezone 15 in the casting direction is 50
mm-250 mm is sufficient.
【００４２】急速冷却装置１４をこのような構成にする
ことにより、急速冷却装置１４における鋳片２のバルジ
ングを防止することが可能となる。尚、図１では２種類
のグリッド１８，１８ａを採用しているが、１種類であ
っても又３種類以上であっても、鋳片２に割れや疵等を
発生させないものであれば、どのような形状であっても
構わない。By configuring the rapid cooling device 14 in this way, it is possible to prevent bulging of the slab 2 in the rapid cooling device 14. Although two types of grids 18 and 18a are used in FIG. 1, as long as one type or three or more types are used as long as they do not cause cracks or flaws in the slab 2, It may have any shape.
【００４３】このような構成の垂直曲げ型スラブ連続鋳
造機１を用いた本発明による直送圧延方法を以下に説明
する。この場合、急速冷却装置１４が上部矯正帯１２か
ら鋳造方向４ｍの位置までの範囲に設置されている前提
で説明する。The direct feed rolling method according to the present invention using the vertical bending type slab continuous casting machine 1 having such a structure will be described below. In this case, description will be made on the assumption that the rapid cooling device 14 is installed in a range from the upper straightening belt 12 to a position 4 m in the casting direction.
【００４４】浸漬ノズル（図示せず）を介して鋳型６内
に溶鋼を鋳造する。溶鋼は鋳型６内で冷却されて凝固殻
３を形成し、内部に未凝固相４を有する鋳片２になる。
この鋳片２をピンチロール９の駆動力により、サポート
ロール７、ガイドロール８及びピンチロール９により支
持しつつ、鋳型６の下方に連続的に引き抜く。引き抜か
れた鋳片２は、上部矯正帯１２において平板状から円弧
状に曲げられ、一方、下部矯正帯１３において円弧状か
ら平板状に曲げ戻される。又、鋳片２はこれら鋳片支持
ロールを通過する間に二次冷却帯で冷却され、鋳片２の
凝固殻３の厚みが増大する。Molten steel is cast into the mold 6 through an immersion nozzle (not shown). The molten steel is cooled in a mold 6 to form a solidified shell 3 and becomes a slab 2 having an unsolidified phase 4 inside.
The slab 2 is continuously pulled out below the mold 6 while being supported by the support roll 7, the guide roll 8 and the pinch roll 9 by the driving force of the pinch roll 9. The drawn slab 2 is bent from the flat plate shape to the circular arc shape in the upper straightening strip 12, and is bent back from the circular arc shape to the flat plate shape in the lower straightening strip 13. Further, the slab 2 is cooled in the secondary cooling zone while passing through these slab supporting rolls, and the thickness of the solidified shell 3 of the slab 2 increases.
【００４５】上部矯正帯１２により矯正された鋳片２
を、冷却水量密度を３０００ｌ／ｍｉｎ・ｍ2 以上とし
た第１ゾーン１６において７００℃以下に冷却し、次い
で、冷却水量密度を１０００ｌ／ｍｉｎ・ｍ2 以上とし
た第２ゾーン１７においてＡr1点以下に冷却する。第１
ゾーン１６で鋳片表面温度を７００℃以下に冷却するこ
とにより、第２ゾーン１７における鋳片表面の伝熱形態
を核沸騰領域と膜沸騰領域との遷移領域に調整すること
ができ、急速冷却装置１４により鋳片２をＡr1点以下ま
で冷却することが可能となる。The slab 2 straightened by the upper straightening strip 12
The cooling water density was cooled to 700 ° C. or less in the first zone 16 and 3000 l / min · m 2 or more, then the following Ar1 point in the second zone 17 that was 1000 l / min · m 2 or more cooling water density Cool to. First
By cooling the slab surface temperature to 700 ° C. or less in the zone 16, the heat transfer form on the slab surface in the second zone 17 can be adjusted to the transition region between the nucleate boiling region and the film boiling region, and the rapid cooling is performed. The device 14 makes it possible to cool the slab 2 to the Ar1 point or less.
【００４６】Ａr1点以下となる保持時間は１０秒間以上
であれば上限値は特に限定されないが、冷却し過ぎると
鋳片２の温度が下がり、直送圧延の省エネルギー効果が
低下するので６０秒程度で十分である。１０秒間以上保
持する理由は、フェライト＋パーライトへの変態を十分
に起こさせるためである。短すぎるとこの変態が完全に
終了せずに復熱してしまい、オーステナイト粒界と硫化
物及び窒化物等の析出位置との分離が完全には実現しな
い可能性があるからである。The upper limit value is not particularly limited as long as the holding time at which the temperature is 1 point or less is 10 seconds or more, but if it is cooled too much, the temperature of the slab 2 decreases and the energy-saving effect of direct feed rolling decreases, so it is about 60 seconds. It is enough. The reason for holding for 10 seconds or more is to sufficiently cause the transformation into ferrite + pearlite. This is because if it is too short, this transformation does not completely end and reheats, and the separation between the austenite grain boundaries and the precipitation positions of sulfides, nitrides and the like may not be realized completely.
【００４７】このように鋳片２を急速に冷却する理由
は、未凝固相４が多量に残留している間に、鋳片表面温
度を一旦Ａr1点以下に下げ、少なくとも１０秒以上Ａr1
点以下に保持した後、復熱させて鋳片表面温度をＡc3点
（フェライト＋パーライトがオーステナイトに変態する
温度）以上に保持するためである。急速冷却しても鋼の
熱拡散が小さいために凝固殻３の内部は温度低下せず、
表面から深さ方向１５ｍｍ程度にしか熱拡散が及ばな
い。この結果、鋳片２の有する顕熱はほとんど失われる
ことがない。ゆっくり冷却すると、表層がＡr1点以下に
なるまでに凝固殻３の内部も冷却され、結果的に顕熱が
失われてしまうが、急速に冷却することで顕熱を失わ
ず、効果的に復熱させることが可能となる。The reason for rapidly cooling the slab 2 in this way is that the slab surface temperature is once lowered to the Ar1 point or lower while the unsolidified phase 4 remains in a large amount, and the Ar1 point is kept for at least 10 seconds or longer.
This is because the temperature of the slab is maintained at the Ac3 point (temperature at which ferrite + pearlite transforms to austenite) or higher after the temperature is maintained below the point and then reheated. Even if rapidly cooled, the temperature of the inside of the solidified shell 3 does not decrease because the heat diffusion of steel is small,
Thermal diffusion reaches only about 15 mm from the surface in the depth direction. As a result, the sensible heat of the slab 2 is hardly lost. If cooled slowly, the inside of the solidified shell 3 will also be cooled by the time the surface layer reaches the Ar1 point or lower, and as a result, sensible heat will be lost. It becomes possible to heat.
【００４８】鋳片２が急速冷却装置１４を通過したなら
ば、二次冷却強度を調整して鋳片表面を復熱させる。鋳
片２は多量の未凝固相４を内部に有しており、二次冷却
強度を調整することで、未凝固相４の凝固潜熱及び顕熱
により鋳片２を容易に復熱させることができる。それ
故、鋳片２が内部に未凝固相４を有しているうちに、鋳
片表面温度がＡc3点以上となるまで鋳片２を復熱させ
る。この場合、鋳片温度を高めるために、垂直曲げ型ス
ラブ連続鋳造機１の出口（機端）付近まで未凝固相４を
残し、連続鋳造機出口直前で鋳片２の凝固を完了させる
ことが好ましい。凝固殻３の潜熱による復熱を連続鋳造
機出口付近まで継続させることができるからである。鋳
片２の有する顕熱及び潜熱のみでは十分に復熱させるこ
とができない場合には、バーナーや誘導加熱等で強制的
に加熱する。After the slab 2 passes through the rapid cooling device 14, the secondary cooling strength is adjusted to reheat the slab surface. The slab 2 has a large amount of unsolidified phase 4 inside, and by adjusting the secondary cooling strength, the slab 2 can be easily reheated by the latent latent heat and sensible heat of the unsolidified phase 4. it can. Therefore, while the slab 2 has the unsolidified phase 4 inside, the slab 2 is reheated until the slab surface temperature reaches the Ac3 point or higher. In this case, in order to raise the temperature of the slab, it is possible to leave the unsolidified phase 4 near the exit (machine end) of the vertical bending slab continuous casting machine 1 and complete the solidification of the slab 2 immediately before the exit of the continuous casting machine. preferable. This is because it is possible to continue the heat recovery due to the latent heat of the solidified shell 3 up to the vicinity of the outlet of the continuous casting machine. If the slab 2 cannot be sufficiently reheated only by sensible heat and latent heat, the slab 2 is forcibly heated by a burner or induction heating.
【００４９】そして、鋳片表面温度をＡc3点以上に保持
したまま、鋳片中心部まで完全に凝固させ、凝固した鋳
片２を連続鋳造機出側に設置したガス切断機１０で所定
長さに切断し、切断した鋳片２をＡc3点以上の高温に保
持したまま搬送台車等により熱間圧延機に搬送して熱間
圧延するか若しくは加熱炉で加熱した後に熱間圧延す
る。Then, with the surface temperature of the slab kept at the Ac3 point or higher, the slab 2 was completely solidified up to the center of the slab, and the solidified slab 2 was set to a predetermined length by the gas cutting machine 10 installed on the outlet side of the continuous casting machine. Then, the cast slab 2 is cut into pieces and conveyed to a hot rolling mill by a carriage or the like while being kept at a high temperature of Ac3 or higher, and hot-rolled or heated in a heating furnace and then hot-rolled.
【００５０】この場合に、鋳片２の温度降下を防止する
ため、垂直曲げ型スラブ連続鋳造機１や搬送台車等に断
熱材を取り付けても良い。更に、ＨＤＲプロセスの場
合、鋳片２を熱間圧延機で圧延する前に、必要に応じて
加熱手段を用い、表面温度を中心温度と同じにする程度
の加熱を行っても良く、又、ＨＣＲプロセスの場合、鋳
片２を加熱炉に装入する前に熱間状態で表面手入れを施
しても良い。In this case, in order to prevent the temperature of the cast slab 2 from dropping, a heat insulating material may be attached to the vertical bending type slab continuous casting machine 1, the carrier, and the like. Furthermore, in the case of the HDR process, before rolling the slab 2 with a hot rolling mill, heating may be performed as necessary to heat the surface temperature to the same level as the center temperature. In the case of the HCR process, surface treatment may be performed in a hot state before charging the slab 2 into the heating furnace.
【００５１】図４は、第１ゾーン１６の鋳造方向長さが
３００ｍｍで冷却水量密度が４４００ｌ／ｍｉｎ・ｍ
2 、第２ゾーン１７の鋳造方向長さが７００ｍｍで冷却
水量密度が１６００ｌ／ｍｉｎ・ｍ2 である急速冷却装
置を上部矯正帯終了位置の直下に設置し、鋳片厚みが２
３０ｍｍである低炭素鋼の鋳片２を鋳片引き抜き速度
２．２ｍ／ｍｉｎで鋳造した場合の伝熱計算による鋳片
表面温度履歴を示す図である。In FIG. 4, the length of the first zone 16 in the casting direction is 300 mm and the cooling water density is 4400 l / min · m.
2 , the second zone 17 has a length in the casting direction of 700 mm and a cooling water amount density of 1600 l / min · m 2 and is installed immediately below the upper straightening zone end position, and the slab thickness is 2
It is a figure which shows the slab surface temperature history by heat transfer calculation at the time of casting the slab 2 of low carbon steel which is 30 mm at a slab drawing speed of 2.2 m / min.
【００５２】図５は、第１ゾーン１６の鋳造方向長さが
３００ｍｍで冷却水量密度が２５００ｌ／ｍｉｎ・ｍ
2 、第２ゾーン１７の鋳造方向長さが７００ｍｍで冷却
水量密度が１０００ｌ／ｍｉｎ・ｍ2 である急速冷却装
置を上部矯正帯終了位置から約６ｍ下流位置に設置し、
鋳片厚みが２３０ｍｍである低炭素鋼の鋳片２を鋳片引
き抜き速度２．２ｍ／ｍｉｎで鋳造した場合の伝熱計算
による鋳片表面温度履歴を示す図である。In FIG. 5, the length of the first zone 16 in the casting direction is 300 mm and the cooling water density is 2500 l / min.m.
2. A rapid cooling device having a length in the casting direction of the second zone 17 of 700 mm and a cooling water amount density of 1000 l / min.m 2 is installed at a position about 6 m downstream from the upper straightening zone end position,
It is a figure which shows the slab surface temperature history by heat transfer calculation at the time of casting the slab 2 of low carbon steel with a slab thickness of 230 mm at a slab drawing speed of 2.2 m / min.
【００５３】又、図６は、第１ゾーン１６の鋳造方向長
さが３００ｍｍで冷却水量密度が２０００ｌ／ｍｉｎ・
ｍ2 、第２ゾーン１７の鋳造方向長さが７００ｍｍで冷
却水量密度が６００ｌ／ｍｉｎ・ｍ2 である急速冷却装
置を下部矯正帯終了位置から約３ｍ下流位置に設置し、
鋳片厚みが２３０ｍｍである低炭素鋼の鋳片２を鋳片引
き抜き速度２．２ｍ／ｍｉｎで鋳造した場合の伝熱計算
による鋳片表面温度履歴を示す図である。Further, FIG. 6 shows that the length of the first zone 16 in the casting direction is 300 mm and the cooling water amount density is 2000 l / min.
m 2 , the second zone 17 has a length in the casting direction of 700 mm and a cooling water amount density of 600 l / min · m 2 , and is installed at a position about 3 m downstream from the lower straightening zone end position,
It is a figure which shows the slab surface temperature history by heat transfer calculation at the time of casting the slab 2 of low carbon steel with a slab thickness of 230 mm at a slab drawing speed of 2.2 m / min.
【００５４】これらの図から明らかなように、急速冷却
装置１４により鋳片表面温度はＡr1点以下まで冷却可能
であることが分かる。尚、図４〜図６は後述する実施例
で用いた垂直曲げ型スラブ連続鋳造機における伝熱計算
結果である。As is apparent from these figures, it is understood that the slab surface temperature can be cooled to the Ar1 point or less by the rapid cooling device 14. 4 to 6 are heat transfer calculation results in the vertical bending type slab continuous casting machine used in Examples described later.
【００５５】このようにして連続鋳造鋳片の直送圧延を
行うことで、鋳片２の表面温度は確実に且つ所定時間Ａ
r1点以下の温度まで一旦冷却されるので、熱間圧延時に
は鋳片２の表層部は微細な再結晶オーステナイト構造に
なり、熱間圧延による表面疵の発生が極めて少なく、表
面性状に優れた鋼板を直送圧延により製造することが可
能となる。又、鋳片表面を一旦Ａr1点以下まで低下させ
る際に急速に低下させるので、鋳片２の有する顕熱はほ
とんど失われることがなく、その後の未凝固相４の顕熱
及び潜熱を利用した復熱により鋳片２を容易にＡc3点以
上することができ、鋳造後の鋳片加熱を必要としない、
省エネルギー効果が大きい高温鋳片を得ることができ
る。By carrying out the direct rolling of the continuously cast slab in this way, the surface temperature of the slab 2 is reliably and for a predetermined time A.
Since it is once cooled to a temperature below the r1 point, the surface layer of the slab 2 has a fine recrystallized austenite structure during hot rolling, and the occurrence of surface defects due to hot rolling is extremely small, and the steel sheet has excellent surface properties. Can be manufactured by direct feed rolling. Also, since the surface of the slab is rapidly lowered when it is once lowered to below the Ar1 point, the sensible heat of the slab 2 is hardly lost, and the sensible heat and latent heat of the unsolidified phase 4 thereafter are utilized. By recuperating heat, the slab 2 can be easily made to have Ac3 points or more, and heating of the slab after casting is not required,
It is possible to obtain a high temperature cast slab having a large energy saving effect.
【００５６】尚、上記説明はスラブ連続鋳造機に関して
行ったが、スラブ連続鋳造機に限らず、ブルーム連続鋳
造機やビレット連続鋳造機でも上記説明に準じて本発明
を実施することができる。Although the above description has been made with respect to the slab continuous casting machine, the present invention can be carried out not only with the slab continuous casting machine but also with the bloom continuous casting machine or the billet continuous casting machine according to the above description.
【００５７】[0057]
【実施例】連続鋳造機の長さ（鋳型上端から機端までの
長さ）が４５ｍ、鋳型長さが０．９ｍ、鋳型上端から上
部矯正帯終了位置までの長さが３．５ｍ、湾曲部の半径
が１０ｍ、下部矯正帯が鋳型上端から１７．５ｍ〜１
９．５ｍの範囲である、急速冷却装置を備えた垂直曲げ
型スラブ連続鋳造機により鋳造した鋳片を用いてＨＤＲ
プロセスによる薄鋼板の製造試験（試験Ｎo.１〜１０）
を実施した。試験では、急速冷却装置により鋳片を冷却
しながら、厚みが２３０ｍｍ、幅が１２００ｍｍの低炭
素鋼鋳片を２．２〜２．４ｍ／ｍｉｎの鋳片引き抜き速
度で鋳造した。[Example] Length of continuous casting machine (length from upper end of mold to machine end) is 45 m, length of mold is 0.9 m, length from upper end of mold to end position of upper straightening strip is 3.5 m, curve The radius of the part is 10 m, and the lower straightening band is 17.5 m to 1 from the upper end of the mold.
HDR using slab cast by vertical bending type slab continuous casting machine equipped with rapid cooling device in the range of 9.5 m
Manufacturing test of thin steel sheet by process (Test No. 1 to 10)
Was carried out. In the test, a low carbon steel slab having a thickness of 230 mm and a width of 1200 mm was cast at a slab drawing speed of 2.2 to 2.4 m / min while cooling the slab with a rapid cooling device.
【００５８】試験Ｎo.１〜４では、図１に示す急速冷却
装置を鋳型上端から４．０ｍ〜６．０ｍ下流の範囲に設
置した。その際に、第１ゾーンの長さを３００ｍｍと３
６０ｍｍの２水準にすると共に、急速冷却装置における
冷却数量密度を種々変更して試験した。急速冷却装置の
鋳造方向長さは、１５０ｍｍ長さのプレゾーンを含めて
合計で２．０ｍである。In Test Nos. 1 to 4, the rapid cooling device shown in FIG. 1 was installed in a range of 4.0 m to 6.0 m downstream from the upper end of the mold. At that time, the length of the first zone is 300 mm and 3
The test was carried out with two levels of 60 mm and various changes in the cooling quantity density in the rapid cooling device. The length of the rapid cooling device in the casting direction is 2.0 m in total including the prezone having a length of 150 mm.
【００５９】試験Ｎo.５〜７では、図１に示す急速冷却
装置を鋳型上端から１２．０ｍ〜１３．１ｍ下流の範囲
に設置した。この場合、プレゾーンの長さを１００ｍ
ｍ、第１ゾーンの長さを３００ｍｍ、第２ゾーンの長さ
を７００ｍｍとし、急速冷却装置における冷却数量密度
を種々変更して試験した。In Test Nos. 5 to 7, the rapid cooling device shown in FIG. 1 was installed in the range of 12.0 m to 13.1 m downstream from the upper end of the mold. In this case, the length of the prezone is 100m
m, the length of the first zone was 300 mm, the length of the second zone was 700 mm, and the cooling quantity density in the rapid cooling device was variously changed and tested.
【００６０】試験Ｎo.８〜１０では、図１に示す急速冷
却装置を鋳型上端から２０．０ｍ〜２１．１ｍ下流の範
囲に設置した。この場合、プレゾーンの長さを１００ｍ
ｍ、第１ゾーンの長さを３００ｍｍ、第２ゾーンの長さ
を７００ｍｍとし、急速冷却装置における冷却数量密度
を種々変更して試験した。In Test Nos. 8 to 10, the rapid cooling device shown in FIG. 1 was installed in the range of 20.0 m to 21.1 m downstream from the upper end of the mold. In this case, the length of the prezone is 100m
m, the length of the first zone was 300 mm, the length of the second zone was 700 mm, and the cooling quantity density in the rapid cooling device was variously changed and tested.
【００６１】又、比較のために、急速冷却装置が設置さ
れず、通常のガイドロール及び二次冷却構造の垂直曲げ
型スラブ連続鋳造機により鋳造した鋳片のＨＤＲプロセ
スによる薄鋼板の製造試験（試験Ｎo.１１〜１３）も実
施した。この場合の鋳造条件は、鋳片冷却条件以外は上
記と同一とした。For comparison, a production test of a thin steel sheet by the HDR process of a slab cast by a vertical guide type slab continuous casting machine having a normal guide roll and a secondary cooling structure without a rapid cooling device installed ( Test Nos. 11 to 13) were also conducted. The casting conditions in this case were the same as above except for the slab cooling conditions.
【００６２】試験では、鋳造中及びガス切断機で切断し
た直後の鋳片表面温度を測定し、又、熱間圧延した薄鋼
板の表面を観察して疵発生率を調査した。そして、鋳片
表面温度及び鋼板の疵発生率に基づき、鋳片のオーステ
ナイトからフェライト＋パーライトへの変態の程度を判
定した。表１に、急速冷却装置を備えた垂直曲げ型スラ
ブ連続鋳造機による試験条件及び試験結果を示し、又、
表２に、急速冷却装置を備えていない垂直曲げ型スラブ
連続鋳造機による試験条件及び試験結果を示す。表１及
び表２における評価の欄の○印は「良好」、△印は「不
良」、×印は「不可」を表示している。In the test, the surface temperature of the slab during casting and immediately after cutting with a gas cutter was measured, and the surface of the hot-rolled thin steel sheet was observed to investigate the defect occurrence rate. Then, based on the surface temperature of the slab and the defect occurrence rate of the steel sheet, the degree of transformation of the austenite of the slab to ferrite + pearlite was determined. Table 1 shows the test conditions and test results by a vertical bending type slab continuous casting machine equipped with a rapid cooling device, and
Table 2 shows the test conditions and the test results by the vertical bending type slab continuous casting machine not equipped with the rapid cooling device. In the evaluation columns in Tables 1 and 2, “good” is indicated by “◯”, “bad” is indicated by “Δ”, and “impossible” is indicated by “x”.
【００６３】[0063]
【表１】 [Table 1]
【００６４】[0064]
【表２】 [Table 2]
【００６５】表１及び表２に示すように、試験Ｎo.１、
試験Ｎo.２、試験Ｎo.５、試験Ｎo.６、試験Ｎo.８、試
験Ｎo.９は急速冷却装置を用いたにも拘わらず、急速冷
却装置における冷却水量の密度が低いため、フェライト
＋パーライトへの変態が完了せず、熱間圧延後の薄鋼板
で疵発生が見られた。試験Ｎo.３は急速冷却装置の第１
ゾーンが３６０ｍｍと長いため、鋳片にバルジングが発
生し、鋳片形状が不均一となり、熱間圧延工程での通板
が不可能となり熱間圧延を中止した。試験Ｎo.１１及び
試験Ｎo.１３はフェライト＋パーライトへの変態が完了
せず、熱間圧延後の薄鋼板で疵発生が見られた。試験Ｎ
o.１２はフェライト＋パーライトへの変態が起こり、薄
鋼板の疵発生率は低かったが、鋳片表面温度が低くなり
すぎ、鋳片加熱原単位が高くなり、ＨＤＲプロセスを採
用するには不適当であった。これに対して、試験Ｎo.
４、試験Ｎo.７、試験Ｎo.１０はフェライト＋パーライ
トへの変態が完了して薄鋼板での疵発生率が低くなり、
且つ鋳片温度を高く保持させることができた。As shown in Tables 1 and 2, test No. 1,
In Test No. 2, Test No. 5, Test No. 6, Test No. 8 and Test No. 9, although the rapid cooling device was used, the density of the cooling water in the rapid cooling device was low, and therefore ferrite + The transformation to pearlite was not completed, and defects were observed in the thin steel sheet after hot rolling. Test No. 3 is the first rapid cooling system
Since the zone was as long as 360 mm, bulging occurred in the slab and the slab shape became non-uniform, making it impossible to pass the strip in the hot rolling process and stopping the hot rolling. In Test No. 11 and Test No. 13, the transformation into ferrite + pearlite was not completed, and defects were observed in the thin steel sheet after hot rolling. Test N
In the case of o.12, transformation to ferrite + pearlite occurred, and the defect occurrence rate of the thin steel sheet was low, but the surface temperature of the slab was too low and the heating unit for slab was too high, which is not suitable for the HDR process. It was suitable. On the other hand, the test No.
4, test No.7, test No.10, the transformation to ferrite + pearlite is completed and the defect occurrence rate in the thin steel sheet becomes low,
Moreover, the slab temperature could be kept high.
【００６６】[0066]
【発明の効果】本発明によれば、鋳片はその表面温度が
Ａr1点の温度まで確実に且つ急速に冷却されて相変態が
生じるので、ＨＤＲプロセスやＨＣＲプロセスにおける
熱間圧延時の表面疵を確実に防止することができ、表面
性状に優れた鋼板を直送圧延方法により製造することが
可能となる。又、鋳片表面を急速に冷却するので、鋳片
の有する顕熱を大幅に失うことなく、その後の未凝固相
の顕熱及び潜熱を利用して省エネルギー効果が大きい高
温鋳片を得ることが可能となる。EFFECTS OF THE INVENTION According to the present invention, since the surface temperature of the cast slab is surely and rapidly cooled to the temperature of the Ar1 point and the phase transformation occurs, the surface flaw at the time of hot rolling in the HDR process or the HCR process. Can be reliably prevented, and a steel sheet having excellent surface properties can be manufactured by the direct-feed rolling method. Further, since the surface of the slab is rapidly cooled, it is possible to obtain a high-temperature slab with a large energy saving effect by utilizing the sensible heat and latent heat of the unsolidified phase after that without significantly losing the sensible heat of the slab. It will be possible.
【図面の簡単な説明】[Brief description of drawings]
【図１】本発明で用いた急速冷却装置の概略図である。FIG. 1 is a schematic view of a rapid cooling device used in the present invention.
【図２】鋳片表面温度と伝熱形態及び熱伝達係数との関
係を示す図である。FIG. 2 is a diagram showing a relationship between a slab surface temperature, a heat transfer form and a heat transfer coefficient.
【図３】本発明の実施の形態を示す図であって、急速冷
却装置を備えた垂直曲げ型スラブ連続鋳造機の側面概略
図である。FIG. 3 is a view showing an embodiment of the present invention and is a schematic side view of a vertical bending slab continuous casting machine equipped with a rapid cooling device.
【図４】本発明を適用した場合の伝熱計算による鋳片表
面温度履歴を示す図である。FIG. 4 is a diagram showing a slab surface temperature history by heat transfer calculation when the present invention is applied.
【図５】本発明を適用した場合の伝熱計算による鋳片表
面温度履歴を示す図である。FIG. 5 is a diagram showing a slab surface temperature history by heat transfer calculation when the present invention is applied.
【図６】本発明を適用した場合の伝熱計算による鋳片表
面温度履歴を示す図である。FIG. 6 is a diagram showing a slab surface temperature history by heat transfer calculation when the present invention is applied.
１ 垂直曲げ型スラブ連続鋳造機 ２ 鋳片 ３ 凝固殻 ４ 未凝固相 ５ 溶鋼湯面 ６ 鋳型 １２ 上部矯正帯 １３ 下部矯正帯 １４ 急速冷却装置 １５ プレゾーン １６ 第１ゾーン １７ 第２ゾーン １８ グリッド １９ スプレーノズル 1 Vertical bending type slab continuous casting machine 2 slab 3 solidified shell 4 Unsolidified phase 5 Molten steel surface 6 molds 12 Upper correction band 13 Lower correction belt 14 Rapid cooling device 15 prezone 16 Zone 1 17 Second zone 18 grid 19 spray nozzles
───────────────────────────────────────────────────── フロントページの続き (72)発明者 上岡 悟史 東京都千代田区丸の内一丁目１番２号 日 本鋼管株式会社内 Ｆターム(参考） 4E004 KA07 KA12 KA14 MA01 MD05 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Satoshi Ueoka 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Main Steel Pipe Co., Ltd. F-term (reference) 4E004 KA07 KA12 KA14 MA01 MD05
Claims (8)
の遷移領域になるように調整した冷却装置を用いて鋳片
をその表面温度がＡr1点以下になるまで冷却し、その
後、冷却強度の調整若しくは断熱や加熱を施して鋳片表
面温度をＡc3点以上に昇温し、鋳片表面温度をＡc3点以
上に保持したまま熱間圧延機まで搬送して、熱間圧延す
ることを特徴とする連続鋳造鋳片の直送圧延方法。1. A slab is cooled using a cooling device adjusted so that the heat transfer form on the surface of the slab is in the transition region between nucleate boiling and film boiling, and then the surface temperature of the slab is cooled to below the Ar1 point. Adjusting the cooling strength or performing heat insulation or heating to raise the surface temperature of the slab to Ac3 point or higher, and carry it to the hot rolling mill while keeping the slab surface temperature at the Ac3 point or higher, and perform hot rolling. A method for directly feeding and rolling continuously cast slabs, which is characterized in that
の遷移領域になるように調整した冷却装置を用いて鋳片
をその表面温度がＡr1点以下になるまで冷却し、その
後、冷却強度の調整若しくは断熱や加熱を施して鋳片表
面温度をＡc3点以上に昇温し、鋳片表面温度をＡc3点以
上に保持したまま加熱炉まで搬送し、加熱炉で加熱した
後に熱間圧延することを特徴とする連続鋳造鋳片の直送
圧延方法。2. A slab is cooled to a surface temperature of Ar 1 point or less by using a cooling device adjusted so that the heat transfer form on the surface of the slab is in the transition region between nucleate boiling and film boiling. Adjusting the cooling strength or performing heat insulation or heating to raise the surface temperature of the slab to Ac3 point or higher, transfer it to the heating furnace while keeping the slab surface temperature at the Ac3 point or higher, and heat it in the heating furnace. A method for directly feeding a continuously cast slab, which comprises performing hot rolling.
して鋳型内溶鋼湯面から鋳造方向８ｍの位置までの範囲
に、鋳造方向の長さが３５０ｍｍ以下であり、冷却水量
密度が３０００ｌ／ｍｉｎ・ｍ2 以上であるスプレーノ
ズルが配置された第１ゾーンと、鋳造方向の長さが５０
０ｍｍ〜１５００ｍｍであり、冷却水量密度が１０００
ｌ／ｍｉｎ・ｍ2 以上であるスプレーノズルと鋳片を支
持するグリッドとが配置された第２ゾーンとを具備する
急速冷却装置を設置し、第１ゾーンで鋳片表面温度を７
００℃以下に冷却して急速冷却装置における鋳片表面の
伝熱形態を核沸騰と膜沸騰との遷移領域に調整し、この
急速冷却装置により鋳片をその表面温度がＡr1点以下に
なるまで冷却することを特徴とする請求項１又は請求項
２に記載の連続鋳造鋳片の直送圧延方法。3. The length in the casting direction is 350 mm or less and the cooling water volume density is 3000 l / in the range from the molten steel level in the mold to the position of 8 m in the casting direction, starting from just below the mold of the curved continuous casting machine. The first zone where the spray nozzle is min.m 2 or more and the length in the casting direction is 50
0 mm to 1500 mm, the cooling water amount density is 1000
A rapid cooling device provided with a second zone in which a spray nozzle having a flow rate of 1 / min · m 2 or more and a grid supporting the slab is arranged is installed, and the slab surface temperature is set to 7 in the first zone.
By cooling to below 00 ° C, the heat transfer form on the surface of the cast piece in the rapid cooling device is adjusted to the transition region between nucleate boiling and film boiling, and until the surface temperature of the cast piece falls below the Ar1 point by this rapid cooling device. It cools, The direct-rolling rolling method of the continuous casting slab of Claim 1 or Claim 2 characterized by the above-mentioned.
位置を開始点として上部矯正帯終了位置から鋳造方向４
ｍの位置までの範囲に、鋳造方向の長さが３５０ｍｍ以
下であり、冷却水量密度が３０００ｌ／ｍｉｎ・ｍ2 以
上であるスプレーノズルが配置された第１ゾーンと、鋳
造方向の長さが５００ｍｍ〜１５００ｍｍであり、冷却
水量密度が１０００ｌ／ｍｉｎ・ｍ2 以上であるスプレ
ーノズルと鋳片を支持するグリッドとが配置された第２
ゾーンとを具備する急速冷却装置を設置し、第１ゾーン
で鋳片表面温度を７００℃以下に冷却して急速冷却装置
における鋳片表面の伝熱形態を核沸騰と膜沸騰との遷移
領域に調整し、この急速冷却装置により鋳片をその表面
温度がＡr1点以下になるまで冷却することを特徴とする
請求項１又は請求項２に記載の連続鋳造鋳片の直送圧延
方法。4. The casting direction 4 from the end position of the upper straightening strip with the end position of the upper straightening strip of the vertical bending type continuous casting machine as the starting point.
In the range up to the position of m, the length in the casting direction is 350 mm or less, the first zone in which the spray nozzle having the cooling water amount density of 3000 l / min · m 2 or more is arranged, and the length in the casting direction is 500 mm. Second with a spray nozzle having a cooling water amount density of 1000 l / min · m 2 or more and a grid supporting the slab is arranged.
A rapid cooling device equipped with a zone is installed, and the surface temperature of the ingot in the rapid cooling device is cooled to 700 ° C. or less in the first zone so that the heat transfer form on the surface of the ingot in the rapid cooling device is in the transition region between nucleate boiling and film boiling. The method for direct feeding and rolling of a continuously cast slab according to claim 1 or 2, wherein the slab is adjusted and the slab is cooled by this rapid cooling device until the surface temperature thereof falls below the Ar1 point.
鋳造方向８ｍの位置を開始点として矯正帯開始位置まで
の範囲に、鋳造方向の長さが３５０ｍｍ以下であり、冷
却水量密度が２０００ｌ／ｍｉｎ・ｍ2 以上であるスプ
レーノズルが配置された第１ゾーンと、鋳造方向の長さ
が５００ｍｍ〜１５００ｍｍであり、冷却水量密度が８
００ｌ／ｍｉｎ・ｍ2 以上であるスプレーノズルと鋳片
を支持するグリッドとが配置された第２ゾーンとを具備
する急速冷却装置を設置し、第１ゾーンで鋳片表面温度
を７００℃以下に冷却して急速冷却装置における鋳片表
面の伝熱形態を核沸騰と膜沸騰との遷移領域に調整し、
この急速冷却装置により鋳片をその表面温度がＡr1点以
下になるまで冷却することを特徴とする請求項１又は請
求項２に記載の連続鋳造鋳片の直送圧延方法。5. The length in the casting direction is 350 mm or less and the cooling water amount density is within the range from the molten steel surface in the mold of the curved continuous casting machine to the straightening zone start position starting from the position of 8 m in the casting direction. A first zone in which a spray nozzle of 2000 l / min · m 2 or more is arranged, a length in the casting direction of 500 mm to 1500 mm, and a cooling water amount density of 8
A rapid cooling device having a second zone in which a spray nozzle having a flow rate of 001 / min · m 2 or more and a grid supporting the slab is arranged is installed, and the surface temperature of the slab is 700 ° C or less in the first zone. Cooling and adjusting the heat transfer morphology of the slab surface in the rapid cooling device to the transition region between nucleate boiling and film boiling,
3. The method for directly feeding and rolling a continuously cast slab according to claim 1 or 2, wherein the slab is cooled by the rapid cooling device until the surface temperature thereof falls below the Ar1 point.
位置から鋳造方向４ｍの位置を開始点として下部矯正帯
開始位置までの範囲に、鋳造方向の長さが３５０ｍｍ以
下であり、冷却水量密度が２０００ｌ／ｍｉｎ・ｍ2 以
上であるスプレーノズルが配置された第１ゾーンと、鋳
造方向の長さが５００ｍｍ〜１５００ｍｍであり、冷却
水量密度が８００ｌ／ｍｉｎ・ｍ2 以上であるスプレー
ノズルと鋳片を支持するグリッドとが配置された第２ゾ
ーンとを具備する急速冷却装置を設置し、第１ゾーンで
鋳片表面温度を７００℃以下に冷却して急速冷却装置に
おける鋳片表面の伝熱形態を核沸騰と膜沸騰との遷移領
域に調整し、この急速冷却装置により鋳片をその表面温
度がＡr1点以下になるまで冷却することを特徴とする請
求項１又は請求項２に記載の連続鋳造鋳片の直送圧延方
法。6. The length in the casting direction is 350 mm or less in the range from the end position of the upper straightening band of the vertical bending type continuous casting machine to the start position of the lower straightening band starting from the position of 4 m in the casting direction, and the amount of cooling water. A first zone in which a spray nozzle having a density of 2000 l / min · m 2 or more is arranged, and a spray nozzle having a length in the casting direction of 500 mm to 1500 mm and a cooling water density of 800 l / min · m 2 or more A rapid cooling device having a second zone in which a grid for supporting the slab is arranged is installed, and the slab surface temperature is cooled to 700 ° C or less in the first zone to transfer the slab surface in the rapid cooling device. The heat form is adjusted to a transition region between nucleate boiling and film boiling, and the slab is cooled by this rapid cooling device until the surface temperature thereof falls below the Ar1 point. A method for directly feeding a continuously cast slab as described.
始点として鋳片切断位置までの範囲に、鋳造方向の長さ
が３５０ｍｍ以下であり、冷却水量密度が１５００ｌ／
ｍｉｎ・ｍ2 以上であるスプレーノズルが配置された第
１ゾーンと、鋳造方向の長さが５００ｍｍ〜１５００ｍ
ｍであり、冷却水量密度が５００ｌ／ｍｉｎ・ｍ2 以上
であるスプレーノズルと鋳片を支持するグリッドとが配
置された第２ゾーンとを具備する急速冷却装置を設置
し、第１ゾーンで鋳片表面温度を７００℃以下に冷却し
て急速冷却装置における鋳片表面の伝熱形態を核沸騰と
膜沸騰との遷移領域に調整し、この急速冷却装置により
鋳片をその表面温度がＡr1点以下になるまで冷却するこ
とを特徴とする請求項１又は請求項２に記載の連続鋳造
鋳片の直送圧延方法。7. The length in the casting direction is 350 mm or less, and the cooling water amount density is 1500 l / in the range from the straightening band end position of the curved continuous casting machine to the slab cutting position as a starting point.
The first zone where the spray nozzle is min.m 2 or more and the length in the casting direction is 500 mm to 1500 m
m, and a rapid cooling device equipped with a second zone in which a spray nozzle having a cooling water volume density of 500 l / min · m 2 or more and a grid supporting a cast piece is arranged, and casting is performed in the first zone. The surface temperature of the cast piece in the rapid cooling device is adjusted to a transition region between nucleate boiling and film boiling by cooling the surface temperature of the casting piece to 700 ° C or less, and the surface temperature of the cast piece is Ar1 point by this rapid cooling device. The method for directly feeding and rolling a continuously cast slab according to claim 1 or 2, wherein the method is cooled until the temperature becomes as follows.
位置を開始点として鋳片切断位置までの範囲に、鋳造方
向の長さが３５０ｍｍ以下であり、冷却水量密度が１５
００ｌ／ｍｉｎ・ｍ2 以上であるスプレーノズルが配置
された第１ゾーンと、鋳造方向の長さが５００ｍｍ〜１
５００ｍｍであり、冷却水量密度が５００ｌ／ｍｉｎ・
ｍ2 以上であるスプレーノズルと鋳片を支持するグリッ
ドとが配置された第２ゾーンとを具備する急速冷却装置
を設置し、第１ゾーンで鋳片表面温度を７００℃以下に
冷却して急速冷却装置における鋳片表面の伝熱形態を核
沸騰と膜沸騰との遷移領域に調整し、この急速冷却装置
により鋳片をその表面温度がＡr1点以下になるまで冷却
することを特徴とする請求項１又は請求項２に記載の連
続鋳造鋳片の直送圧延方法。8. The length in the casting direction is 350 mm or less and the cooling water amount density is 15 in a range from the end position of the lower straightening band of the vertical bending type continuous casting machine to the cutting position of the slab as a starting point.
A first zone in which a spray nozzle of 001 / min · m 2 or more is arranged, and a length in the casting direction of 500 mm to 1
500 mm, cooling water volume density is 500 l / min.
A rapid cooling device having a second zone in which a spray nozzle having a size of m 2 or more and a grid supporting the slab is arranged is installed, and the slab surface temperature is cooled to 700 ° C. or less in the first zone to rapidly cool the slab. The heat transfer mode of the surface of the cast piece in the cooling device is adjusted to a transition region between nucleate boiling and film boiling, and the cast piece is cooled by this rapid cooling device until the surface temperature thereof becomes below the Ar1 point. The method for directly feeding and rolling a continuously cast slab according to claim 1 or 2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002059813A JP4055440B2 (en) | 2001-06-13 | 2002-03-06 | Direct-rolling method for continuous cast slabs |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001178623 | 2001-06-13 | ||
| JP2001-178623 | 2001-06-13 | ||
| JP2002059813A JP4055440B2 (en) | 2001-06-13 | 2002-03-06 | Direct-rolling method for continuous cast slabs |
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| Publication Number | Publication Date |
|---|---|
| JP2003062647A true JP2003062647A (en) | 2003-03-05 |
| JP4055440B2 JP4055440B2 (en) | 2008-03-05 |
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|---|---|---|---|
| JP2002059813A Expired - Lifetime JP4055440B2 (en) | 2001-06-13 | 2002-03-06 | Direct-rolling method for continuous cast slabs |
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| JP4692164B2 (en) * | 2005-09-02 | 2011-06-01 | Ｊｆｅスチール株式会社 | Continuous casting method of high carbon steel |
| JP2007061888A (en) * | 2005-09-02 | 2007-03-15 | Jfe Steel Kk | Method for continuously casting high carbon steel |
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| US10974316B2 (en) | 2016-01-29 | 2021-04-13 | Nippon Steel Corporation | Secondary cooling method and secondary cooling device for casting product in continuous casting |
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| KR20220017493A (en) * | 2019-07-11 | 2022-02-11 | 제이에프이 스틸 가부시키가이샤 | Secondary cooling method and secondary cooling device for continuous casting slabs |
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| KR102638366B1 (en) * | 2019-07-11 | 2024-02-19 | 제이에프이 스틸 가부시키가이샤 | Secondary cooling method and device for continuous casting cast steel |
| CN114173958A (en) * | 2019-08-02 | 2022-03-11 | 杰富意钢铁株式会社 | Secondary cooling device and secondary cooling method for continuous casting of cast piece |
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