JPH09206896A - Electromagnetic stirring device in die, and continuous casting method of steel - Google Patents
Electromagnetic stirring device in die, and continuous casting method of steelInfo
- Publication number
- JPH09206896A JPH09206896A JP1730396A JP1730396A JPH09206896A JP H09206896 A JPH09206896 A JP H09206896A JP 1730396 A JP1730396 A JP 1730396A JP 1730396 A JP1730396 A JP 1730396A JP H09206896 A JPH09206896 A JP H09206896A
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- Prior art keywords
- mold
- molten steel
- downward
- steel
- continuous casting
- Prior art date
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、表層部に気泡や非
金属介在物が少ない鋳片を製造するための鋳型内電磁攪
拌装置および鋼の連続鋳造方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic stirrer in a mold and a continuous casting method for steel for producing a slab with few bubbles and non-metallic inclusions in the surface layer.
【０００２】[0002]
【従来の技術】自動車のボディ等に用いられる薄鋼板
は、その表面に疵がないものが求められている。一般
に、鋳片の表層部に存在する気泡や非金属介在物は圧延
時に表面に露出し表面疵となることが知られている。し
たがって、表面疵を低減するためには鋳片の表層部に存
在する気泡や非金属介在物を少なくする必要がある。特
に、鋳片の表面から１０mm以内の範囲における１００μ
ｍ以上の気泡や非金属介在物を十分除去することが重要
である。連続鋳造においては、鋳片は鋳型およびその下
方にある二次冷却帯で冷却され凝固シェルが発達してい
く。鋳造速度や鋳型での冷却条件等によっても異なる
が、通常の連続鋳造で用いられる長さ８００〜１０００
mmの鋳型を用いると、鋳片の表面から１０mm以内の凝固
はほぼ鋳型内で完了する。したがって、凝固シェルに気
泡や非金属介在物が捕捉されないように、鋳型内での溶
鋼流動を制御することが重要である。2. Description of the Related Art Thin steel sheets used for automobile bodies are required to have no flaws on their surfaces. It is generally known that air bubbles and non-metallic inclusions present in the surface layer of the cast slab are exposed on the surface during rolling and cause surface defects. Therefore, in order to reduce surface defects, it is necessary to reduce bubbles and non-metallic inclusions existing in the surface layer of the cast slab. Especially 100μ in the range within 10mm from the surface of the slab
It is important to sufficiently remove bubbles and non-metallic inclusions of m or more. In continuous casting, the slab is cooled in the mold and the secondary cooling zone below it, and the solidified shell develops. The length used in normal continuous casting is 800 to 1000, although it varies depending on the casting speed and cooling conditions in the mold.
With a mm mold, solidification within 10 mm from the surface of the slab is almost complete in the mold. Therefore, it is important to control the molten steel flow in the mold so that air bubbles and non-metallic inclusions are not captured by the solidified shell.
【０００３】一般に、鋼の連続鋳造において、浸漬ノズ
ルより鋳型内に供給された溶鋼は、図３に示すように、
凝固シェルに衝突し、上下ふたつの流れに分かれる。こ
のため、鋳型上部では、上向きの流れとなり、鋳型下部
では下向きの流れとなる。従来は鋳型下部での下向き流
れによって、気泡や介在物の浮上が阻害されていると考
えられ、上向きの溶鋼流動を付与し気泡や非金属介在物
の浮上を促進しようとしていた。Generally, in continuous casting of steel, the molten steel supplied from the immersion nozzle into the mold is as shown in FIG.
It collides with the solidified shell and splits into two upper and lower streams. Therefore, the upper part of the mold has an upward flow, and the lower part of the mold has a downward flow. In the past, it was thought that the downward flow in the lower part of the mold hindered the levitation of bubbles and inclusions, and tried to impart upward molten steel flow to promote the levitation of bubbles and non-metallic inclusions.
【０００４】一方、従来の鋳型内に組み込まれた電磁攪
拌装置は、図４に示すように水平に電磁力１を付与する
ものが一般的である。水平に電磁力を付与する目的でス
ロット２は鋳型幅方向に並べられている。この技術は、
上下方向の流れには着目せずに流速を増加させることで
気泡や非金属介在物の凝固シェルへの付着防止を行うも
のである。これに対して、図５に示すように、電磁攪拌
装置を用いて溶鋼を鋳型内壁面で上向きに流動させなが
ら連続鋳造を行なう方法が特開昭６１−１４０３５７号
公報に開示されている。この方法は、上向きの電磁力３
を付与し、鋳型回りの溶鋼流を上向きにして、気泡や非
金属介在物の浮上を促進するものである。このとき、リ
ニアモーター４は各長辺５および各短辺６の脇に設置さ
れ、スロット２は鋳造方向７に並べられている。On the other hand, a conventional electromagnetic stirrer incorporated in a mold generally applies an electromagnetic force 1 horizontally as shown in FIG. The slots 2 are arranged in the mold width direction for the purpose of horizontally applying an electromagnetic force. This technology is
Without paying attention to the flow in the vertical direction, the flow velocity is increased to prevent bubbles and non-metallic inclusions from adhering to the solidified shell. On the other hand, as shown in FIG. 5, Japanese Patent Application Laid-Open No. 61-140357 discloses a method of performing continuous casting while flowing molten steel upward on the inner wall surface of a mold using an electromagnetic stirrer. This method uses the upward electromagnetic force 3
Is applied to make the molten steel flow around the mold upward and promote the floating of bubbles and non-metallic inclusions. At this time, the linear motor 4 is installed beside each long side 5 and each short side 6, and the slots 2 are arranged in the casting direction 7.
【０００５】[0005]
【発明が解決しようとする課題】しかしながら、後述す
るように、溶鋼流動を上向きにした場合には、かえって
気泡や非金属介在物が凝固シェル内面に付着しやすくな
るため、鋳片表層部の気泡や非金属介在物の数が多くな
る。さらに、鋳型内溶鋼のメニスカス位置の変動が大き
くなるため、モールドパウダーの巻き込みが増加し、巻
き込まれたモールドパウダーがそのまま非金属介在物と
して鋳片内に残存するという問題点もある。However, as will be described later, when the flow of molten steel is directed upward, bubbles and non-metallic inclusions tend to adhere to the inner surface of the solidified shell, and therefore bubbles in the surface layer of the cast slab. And the number of non-metallic inclusions increases. Further, since the fluctuation of the meniscus position of the molten steel in the mold becomes large, the entrainment of the mold powder increases, and the encased mold powder remains as a non-metallic inclusion in the cast piece.
【０００６】本発明は、このような鋼の連続鋳造におい
て、表層部の気泡や非金属介在物が少ない鋳片を得るこ
とができる鋳型内電磁攪拌装置およびこれを用いる連続
鋳造方法を提供することを目的とする。The present invention provides an electromagnetic stirrer in a mold capable of obtaining a slab with a small amount of bubbles and non-metallic inclusions in the surface layer in such continuous casting of steel, and a continuous casting method using the same. With the goal.
【０００７】[0007]
【課題を解決するための手段】本発明は上記課題を解決
するために考案されたもので、その要旨は、 （１）スラブ用連続鋳造鋳型において、鋳型長辺の両側
に、鉄芯幅が最大鋳造幅の８割以上であり、下向きの電
磁力を溶鋼に与えるリニアモーターを設置することを特
徴とする鋳型内電磁攪拌装置。 （２）スラブ用連続鋳造鋳型において、鋳型長辺の中心
付近から端付近にかけて一箇所、計４箇所に鉄芯幅が最
大鋳型幅の４割以上であり、下向きの電磁力を溶鋼に与
えるリニアモーターを設置することを特徴とする鋳型内
電磁攪拌装置。 （３）（１）或いは（２）記載の装置を用いて、鋳型内
の凝固シェルの厚みが０mm以上１０mm以下の範囲で、凝
固シェルと溶鋼との界面から２０mm以内の範囲における
溶鋼流の鉛直成分を鋳造幅方向に均一に下向きに制御す
ることを特徴とする鋼の連続鋳造方法。 （４）（１）或いは（２）記載の装置を用いて、凝固シ
ェルと溶鋼との界面から２０mmの位置における溶鋼流速
の鉛直下向き成分を鋳造幅方向に均一に５cm/s以上５０
cm/s以下に制御することを特徴とする鋼の連続鋳造方
法。である。The present invention has been devised to solve the above-mentioned problems, and its gist is (1) a continuous casting mold for slabs, in which iron core widths are provided on both sides of the long side of the mold. An electromagnetic stirrer in a mold, which is 80% or more of the maximum casting width and is provided with a linear motor that gives a downward electromagnetic force to molten steel. (2) In the continuous casting mold for slabs, the iron core width is 40% or more of the maximum mold width at one place from the center to the end of the long side of the mold, a total of four places, and a linear electromagnetic force that gives downward electromagnetic force to molten steel. An electromagnetic stirrer in a mold, which is equipped with a motor. (3) Using the apparatus described in (1) or (2), the vertical direction of the molten steel flow in the range where the thickness of the solidified shell in the mold is 0 mm or more and 10 mm or less and within 20 mm from the interface between the solidified shell and the molten steel. A continuous casting method for steel, which comprises controlling the components uniformly downward in the casting width direction. (4) Using the apparatus described in (1) or (2), the vertically downward component of the molten steel flow velocity at a position of 20 mm from the interface between the solidified shell and the molten steel is uniformly 5 cm / s or more in the casting width direction 50
A continuous casting method for steel, which is characterized by controlling to cm / s or less. It is.
【０００８】[0008]
【発明の実施の形態】鋳片表層部の気泡の数に及ぼす鋳
型内の溶鋼流速の影響を図６に示す。ここで、溶鋼流速
は凝固シェルと溶鋼との界面から２０mmの位置での鉛直
成分であり、鋳片内の一次デンドライトアームの鋳片表
面に垂直な方向からの傾き角度より求めた。気泡の数
は、鋳片の表面から１０mm以内の範囲における１００μ
ｍ以上の気泡の単位面積当たりの数である。溶鋼流速の
鉛直成分が下向きに５cm/s以上であれば鋳片表層部の気
泡の数が少なくなり、圧延後も表面疵がほとんど発生し
ない。すなわち、気泡は従来考えてられていたように、
上昇流を利用して、気泡を湯面に運ぶよりも、むしろ凝
固シェル近傍の溶鋼を下降流に制御する方が良い品質が
得られている。BEST MODE FOR CARRYING OUT THE INVENTION FIG. 6 shows the effect of the molten steel flow rate in the mold on the number of bubbles in the surface layer of the cast slab. Here, the molten steel flow velocity is a vertical component at a position of 20 mm from the interface between the solidified shell and the molten steel, and was obtained from the inclination angle of the primary dendrite arm in the slab from the direction perpendicular to the surface of the slab. The number of bubbles is 100μ within 10mm from the surface of the slab.
It is the number of bubbles of m or more per unit area. When the vertical component of the molten steel flow rate is 5 cm / s or more downward, the number of bubbles in the surface layer of the cast slab is small and surface defects are hardly generated even after rolling. That is, the bubbles are, as previously thought,
Better quality is obtained by controlling the molten steel near the solidified shell to the downflow rather than using the upflow to bring bubbles to the surface of the molten metal.
【０００９】鋳片表層部の非金属介在物の数に及ぼす鋳
型内の溶鋼流速の影響を図７に示す。ここで、溶鋼流速
は凝固シェルと溶鋼との界面から２０mmの位置での鉛直
成分であり、鋳片内の一次デンドライトアームの鋳片表
面に垂直な方向からの傾き角度より求めた。非金属介在
物の数は、鋳片の表面から１０mm以内の範囲における１
００μｍ以上の非金属介在物の単位面積当たりの数であ
る。溶鋼流速の鉛直成分が下向きに５cm/s以上であれば
鋳片表層部の非金属介在物の数が少なくなる。しかし、
下向きの溶鋼流速が５０cm/s超になると非金属介在物の
個数が増加する。これは、下向きの流れによって、鋳型
内溶鋼のメニスカス部にあるモールドフラックスが溶鋼
中に巻き込まれるために生じる非金属介在物の増加が原
因である。溶鋼中に巻き込まれる非金属介在物は下向き
流速が大きくなるほど多くなる。このことは、気泡と同
様に非金属介在物についても、凝固シェル近傍の溶鋼を
下降流に制御することが品質向上には有効であるが、下
降流速には上限が存在することを示している。FIG. 7 shows the effect of the flow rate of molten steel in the mold on the number of non-metallic inclusions in the surface layer of the cast slab. Here, the molten steel flow velocity is a vertical component at a position of 20 mm from the interface between the solidified shell and the molten steel, and was obtained from the inclination angle of the primary dendrite arm in the slab from the direction perpendicular to the surface of the slab. The number of non-metallic inclusions is 1 within the range of 10 mm from the surface of the slab.
It is the number per unit area of non-metallic inclusions of 00 μm or more. If the vertical component of the molten steel flow rate is 5 cm / s or more downward, the number of non-metallic inclusions on the surface layer of the cast slab will decrease. But,
When the downward molten steel flow velocity exceeds 50 cm / s, the number of nonmetallic inclusions increases. This is because the downward flow causes an increase in non-metallic inclusions caused by the mold flux in the meniscus portion of the molten steel in the mold being caught in the molten steel. The amount of non-metallic inclusions entrained in the molten steel increases as the downward flow velocity increases. This indicates that for non-metallic inclusions as well as bubbles, controlling molten steel in the vicinity of the solidified shell to a downward flow is effective for quality improvement, but there is an upper limit for the downward flow velocity. .
【００１０】したがって、鋳片の表層部、特に、鋳片の
表面から１０mm以内の気泡と非金属介在物の個数を低減
するためには、連続鋳造時に、湯面付近から鋳型下端付
近（鋳片表面から１０mmまでの凝固が完了する位置）ま
での範囲において、凝固が凝固シェルと溶鋼との界面か
ら２０mmの位置での溶綱流速の鉛直成分を下向きに５cm
/s以上５０cm/s以下にすることが必要である。Therefore, in order to reduce the number of bubbles and non-metallic inclusions within 10 mm from the surface layer of the slab, particularly the surface of the slab, during continuous casting, from near the molten metal surface to near the lower end of the mold (the slab is In the range from the surface to the position where solidification is completed up to 10 mm), the vertical component of the molten steel flow velocity at the position where solidification is 20 mm from the interface between the solidified shell and the molten steel is 5 cm downward.
It is necessary to set it to be not less than / s and not more than 50 cm / s.
【００１１】上記の溶鋼流を得るための鋳型内電磁攪拌
装置および鋼の連続鋳造方法を図１に基づいて説明す
る。鋳型長辺５の両側に鉄芯幅８が最大鋳造幅の８割以
上であり下向きの電磁力９を溶鋼に与えるリニアモータ
ー４を設置する。下向きの電磁力９を付与するので、ス
ロット２は鋳造方向７に並べられており、従来技術の水
平に電磁力を付与するためのスロットが鋳造幅方向に並
べられた装置（図４）とは基本的に異なる。また、本発
明装置は、リニアモーターを長辺５両側のみに設置し、
下向きの電磁力９を付与するので、各長辺と各短辺の脇
にリニアモーターを設置し、上向きの電磁力を付与する
従来技術（図５）とも根本的に異なる。An electromagnetic stirrer in a mold and a continuous casting method for steel for obtaining the above molten steel flow will be described with reference to FIG. On both sides of the long side 5 of the mold, the linear motors 4 having the iron core width 8 of 80% or more of the maximum casting width and applying downward electromagnetic force 9 to molten steel are installed. Since the downward electromagnetic force 9 is applied, the slots 2 are arranged in the casting direction 7, which is different from the prior art device in which the slots for horizontally applying electromagnetic force are arranged in the casting width direction (FIG. 4). Basically different. Further, in the device of the present invention, the linear motors are installed only on both sides of the long side 5,
Since the downward electromagnetic force 9 is applied, it is fundamentally different from the prior art (FIG. 5) in which a linear motor is installed beside each long side and each short side and an upward electromagnetic force is applied.
【００１２】本発明装置のリニアモーター４の配置によ
り、鋳型長辺のほぼ全域に下向きの電磁力が付与される
ので、鋳型長辺全域において凝固シェル近傍において均
一な下降流が形成される（流動パターンについては図８
を参照）。さらに、下降流に制御するので、凝固シェル
への気泡や非金属介在物の捕捉が少ない（図６、７）。
もし、鉄芯幅８が最大鋳造幅の８割よりも小さい場合、
特に最大鋳造幅の鋳造時に下降流が不均一になるおそれ
がある。鉄芯幅８が最大鋳造幅の８割以上であれば如何
なる鋳造幅でも均一な下降流を得ることができる。By the arrangement of the linear motor 4 of the device of the present invention, a downward electromagnetic force is applied to almost the entire long side of the mold, so that a uniform downward flow is formed in the vicinity of the solidification shell in the entire long side of the mold (flow). Figure 8 for the pattern
See). Furthermore, since the flow is controlled to descend, trapping of air bubbles and non-metallic inclusions in the solidified shell is small (FIGS. 6 and 7).
If the iron core width 8 is smaller than 80% of the maximum casting width,
In particular, there is a possibility that the downflow becomes non-uniform during casting with the maximum casting width. If the iron core width 8 is 80% or more of the maximum casting width, a uniform downflow can be obtained with any casting width.
【００１３】前記のごとく、鋳片の表面から１０mmの凝
固が完了するまでの範囲はほぼ鋳型全長であるので、下
降流は湯面１０付近から鋳型下端１１付近まで発生させ
る必要がある。このためには、鉄芯の高さ１２が２００
mm以上であれば十分である。また、リニアモーター４を
設置する鋳造方向７の位置は鋳型内であればどこでも良
い。リニアモーター４よりも上方や下方の鋳型内溶鋼は
電磁力により発生した下降流の慣性でやはり下降流とな
る。溶鋼に与える電磁力の大きさは凝固シェルと溶鋼と
の界面から２０mmの位置で１０3 Ｎ／ｍ3 から１０6 Ｎ
／ｍ3 までの範囲であれば、この位置において５cm/s以
上５０cm/s以下の流速を得ることは可能である。As described above, the range from the surface of the slab to the completion of solidification of 10 mm is almost the entire length of the mold, so that the downflow must be generated from the vicinity of the molten metal surface 10 to the vicinity of the lower end 11 of the mold. For this, the height 12 of the iron core is 200
mm or more is sufficient. The position of the linear motor 4 in the casting direction 7 may be anywhere in the mold. The molten steel in the mold above and below the linear motor 4 also becomes a downward flow due to the inertia of the downward flow generated by the electromagnetic force. The magnitude of the electromagnetic force applied to the molten steel is 10 3 N / m 3 to 10 6 N at a position 20 mm from the interface between the solidified shell and the molten steel.
It is possible to obtain a flow velocity of 5 cm / s or more and 50 cm / s or less at this position in the range up to / m 3 .
【００１４】同様の溶鋼流を得るためのもう一つの鋳型
内電磁攪拌装置および鋼の連続鋳造方法を図２に基づい
て説明する。鋳型長辺の中心１３付近から端１４付近に
かけての計４箇所に鉄芯幅８が最大鋳型幅の４割以上で
あり、下向きの電磁力９を溶鋼に与えるリニアモーター
４を設置する。鋳型長辺中心１３付近の電磁力は弱まる
ものの、ほぼ全域に電磁力を付与しているので、前記し
た鋳型電磁攪拌装置と同様に鋳型長辺５全域において凝
固シェル近傍の溶鋼流が均一な下降流となる。また、こ
の鋳型内電磁攪拌装置を用いた鋼の連続鋳造方法におけ
る、鉄芯の高さ１２、鋳造方向７の設置位置、電磁力の
大きさは前記した鋳型内電磁攪拌装置での鋼の連続鋳造
方法と同じである。ただし、この鋳型内電磁攪拌装置
は、４つのリニアモーターを違う電源と接続することに
より、それぞれ異なる大きさの電磁力を溶鋼に付与する
ことが可能であり、特に偏流の制御をすることにも応用
できる可能性がある。Another electromagnetic stirrer in a mold and a continuous steel casting method for obtaining a similar molten steel flow will be described with reference to FIG. The iron core width 8 is 40% or more of the maximum mold width at a total of four places from the center 13 of the long side of the mold to the vicinity of the end 14, and the linear motors 4 that apply downward electromagnetic force 9 to the molten steel are installed. Although the electromagnetic force near the center 13 of the long side of the mold is weakened, the electromagnetic force is applied to almost the entire region, so that the molten steel flow near the solidification shell uniformly descends over the entire long side 5 of the mold as in the electromagnetic stirring device described above. It becomes a flow. Further, in the continuous casting method of steel using the electromagnetic stirrer in the mold, the height 12 of the iron core, the installation position in the casting direction 7, and the magnitude of the electromagnetic force are the continuous steel of the steel in the electromagnetic stirrer in the mold described above. It is the same as the casting method. However, this in-mold electromagnetic stirrer can apply different electromagnetic forces to molten steel by connecting four linear motors to different power sources, and especially to control drift. There is a possibility that it can be applied.
【００１５】以上の本発明方式の鋼の電磁攪拌装置およ
び方法を利用すると、図８に示すような、凝固シェルと
溶鋼の界面近傍全域において下降流である流動パターン
を得ることができ、鋳片表面の気泡や非金属介在物を減
少させることが可能になる。By utilizing the above-described electromagnetic stirrer and method for steel according to the present invention, it is possible to obtain a downward flow pattern in the entire vicinity of the interface between the solidified shell and the molten steel as shown in FIG. It is possible to reduce bubbles and non-metallic inclusions on the surface.
【００１６】[0016]
【実施例】重量％で、Ｃ：０．００１〜０．００６、Ｓ
ｉ：０．００５〜０．０２、Ｍｎ：０．０５〜０．２、
Ｐ：０．０１〜０．０２、Ｓ：０．００２〜０．０２、
Ａｌ：０．０２〜０．１、Ｔｉ：０．００１〜０．０
５、残部Ｆｅおよび不可避的不純物元素よりなる鋼を連
続鋳造した。鋳片の幅は１５００mm、厚みは２４０mmで
あり、鋳造速度は１．５ m/minである。このとき、リニ
アモーターは、図１に示すように、鉄芯幅は１５００mm
であり、鋳型長辺の両側の、溶鋼湯面から５０mmから４
００mmの範囲（鋳型長さは８００mm）に設置した。オフ
ラインでの電磁力測定では、鋳型表面から２０mmの位置
（溶鋼湯面での凝固シェルと溶鋼との界面から２０mmの
位置）において１．５×１０4 Ｎ／ｍ3 、３０mmの位置
（鋳型下端での凝固シェルと溶鋼との界面から２０mmの
位置）において１．２×１０4 Ｎ／ｍ3 であった。比較
例はリニアモーター型の電磁攪拌装置を用いて、鋳型内
の鋳型壁近傍の溶鋼流が上向きとなるようにした場合で
ある。EXAMPLES In weight%, C: 0.001-0.006, S
i: 0.005 to 0.02, Mn: 0.05 to 0.2,
P: 0.01 to 0.02, S: 0.002 to 0.02,
Al: 0.02 to 0.1, Ti: 0.001 to 0.0
5. Continuously cast steel consisting of the balance of Fe and unavoidable impurity elements. The width of the slab is 1500 mm, the thickness is 240 mm, and the casting speed is 1.5 m / min. At this time, the linear motor has an iron core width of 1500 mm as shown in FIG.
And 50 mm to 4 mm from the molten steel surface on both sides of the long side of the mold.
It was installed in the range of 00 mm (mold length is 800 mm). In the offline electromagnetic force measurement, at a position of 20 mm from the mold surface (20 mm from the interface between the solidified shell and the molten steel on the molten steel surface), a position of 1.5 × 10 4 N / m 3 and 30 mm (the lower end of the mold) Was 1.2 × 10 4 N / m 3 at the position 20 mm from the interface between the solidified shell and the molten steel. In the comparative example, a linear motor type electromagnetic stirrer is used so that the molten steel flow in the vicinity of the mold wall in the mold is directed upward.
【００１７】本発明の方法では、凝固シェル厚が１０mm
までの範囲では、凝固シェルから２０mmの位置での溶鋼
流速は鉛直下向きに５〜５０cm/sであった。一方、比較
例の方法では、凝固シェル厚が１０mmまでの範囲では、
凝固シェルから２０mmの位置での溶鋼流速は鉛直上向き
に５〜５０cm/sであった。In the method of the present invention, the solidified shell thickness is 10 mm.
In the range up to, the molten steel flow velocity at a position of 20 mm from the solidified shell was 5 to 50 cm / s vertically downward. On the other hand, in the method of the comparative example, in the range of the solidified shell thickness up to 10 mm,
The molten steel flow velocity at a position of 20 mm from the solidified shell was 5 to 50 cm / s vertically upward.
【００１８】鋳片の表面から１０mm以内に存在する１０
０μｍ以上の気泡と非金属介在物の個数を調査した結
果、表１に示すように本発明の方法では、比較例に比べ
て気泡の個数、非金属介在物の個数ともに１／１０以下
に減少した。10 within 10 mm from the surface of the slab
As a result of investigating the number of bubbles and non-metallic inclusions of 0 μm or more, as shown in Table 1, in the method of the present invention, both the number of bubbles and the number of non-metallic inclusions are reduced to 1/10 or less as compared with the comparative example. did.
【００１９】[0019]
【表１】 [Table 1]
【００２０】[0020]
【発明の効果】本発明の装置および方法により、表層部
に気泡や非金属介在物が少ない鋳片を容易に製造するこ
とができる。このため、本発明で製造される鋳片を熱間
圧延、冷間圧延して製造される薄鋼板の表面品質が向上
するとともに、表面欠陥起因の不良品の発生が減少し、
歩留まりを向上させることができる。According to the apparatus and method of the present invention, it is possible to easily manufacture a slab having few bubbles and non-metallic inclusions in the surface layer portion. Therefore, hot rolling the slab produced in the present invention, the surface quality of the thin steel sheet produced by cold rolling is improved, the occurrence of defective products due to surface defects is reduced,
The yield can be improved.
【図１】本発明の電磁力を与える装置を示す図。FIG. 1 is a diagram showing an apparatus for applying an electromagnetic force of the present invention.
【図２】本発明の電磁力を与える装置を示す図。FIG. 2 is a diagram showing an apparatus for applying an electromagnetic force of the present invention.
【図３】通常の連続鋳造における鋳型内の溶鋼流動を示
す図。FIG. 3 is a diagram showing molten steel flow in a mold in normal continuous casting.
【図４】水平方向の電磁力を付与する電磁攪拌装置を示
す図。FIG. 4 is a diagram showing an electromagnetic stirrer that applies a horizontal electromagnetic force.
【図５】上向きの電磁力を付与する電磁攪拌装置を示す
図。FIG. 5 is a diagram showing an electromagnetic stirrer for applying an upward electromagnetic force.
【図６】鋳型内の溶鋼流速と鋳片表層部の気泡個数との
関係を示す図。FIG. 6 is a diagram showing the relationship between the flow rate of molten steel in the mold and the number of bubbles in the surface layer of the slab.
【図７】鋳型内の溶鋼流速と鋳片表層部の非金属介在物
の個数を示す図。FIG. 7 is a diagram showing the flow rate of molten steel in the mold and the number of non-metallic inclusions on the surface layer of the slab.
【図８】本発明の方法を適用した場合の鋳型内の溶鋼流
動を示す図。FIG. 8 is a diagram showing molten steel flow in a mold when the method of the present invention is applied.
１：水平方向の電磁力 ２：スロット ３：上向きの電磁力 ４：リニアモーター ５：鋳型長辺 ６：鋳型短辺 ７：鋳造方向 ８：鉄芯幅 ９：下向きの電磁力 １０：溶鋼湯面 １１：鋳型下端 １２：鉄芯高さ １３：鋳型長辺の中心 １４：鋳型長辺の端 1: Horizontal electromagnetic force 2: Slot 3: Upward electromagnetic force 4: Linear motor 5: Mold long side 6: Mold short side 7: Casting direction 8: Iron core width 9: Downward electromagnetic force 10: Molten steel surface 11: Lower end of mold 12: Height of iron core 13: Center of long side of mold 14: End of long side of mold
───────────────────────────────────────────────────── フロントページの続き (72)発明者 岸田 豊 神奈川県川崎市中原区井田1618番地 新日 本製鐵株式会社技術開発本部内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yutaka Kishida 1618 Ida, Nakahara-ku, Kawasaki-shi, Kanagawa Nippon Steel Corporation Technology Development Division
Claims (4)
おいて、鋳型長辺の両側に、鉄芯幅が最大鋳造幅の８割
以上であり、下向きの電磁力を溶鋼に与えるリニアモー
ターを設置することを特徴とする鋳型内電磁攪拌装置。1. In a continuous casting mold electromagnetic stirrer for slabs, a linear motor having an iron core width of 80% or more of the maximum casting width and applying downward electromagnetic force to molten steel is installed on both sides of the long side of the mold. An electromagnetic stirring device in a mold, which is characterized in that
おいて、鋳型長辺の中心付近から端付近にかけて一箇
所、計４箇所に鉄芯幅が最大鋳型幅の４割以上であり、
下向きの電磁力を溶鋼に与えるリニアモーターを設置す
ることを特徴とする鋳型内電磁攪拌装置。2. An electromagnetic stirrer in a continuous casting mold for a slab, wherein the iron core width is 40% or more of the maximum mold width at a total of 4 positions from near the center to near the end of the long side of the mold.
An electromagnetic stirrer in a mold, which is equipped with a linear motor that applies downward electromagnetic force to molten steel.
鋳型内の凝固シェルの厚みが０mm以上１０mm以下の範囲
で、凝固シェルと溶鋼との界面から２０mm以内の範囲に
おける溶鋼流の鉛直成分を鋳造幅方向に均一に下向きに
制御することを特徴とする鋼の連続鋳造方法。3. Using the device according to claim 1 or 2,
It is characterized in that the vertical component of the molten steel flow in the range of 20 mm or less from the interface between the solidified shell and the molten steel is controlled downward uniformly in the casting width direction when the thickness of the solidified shell in the mold is 0 mm or more and 10 mm or less. Continuous casting method for steel.
凝固シェルと溶鋼との界面から２０mmの位置における溶
鋼流速の鉛直下向き成分を鋳造幅方向に均一に５cm/s以
上５０cm/s以下に制御することを特徴とする鋼の連続鋳
造方法。4. Using the device according to claim 1 or 2,
A continuous casting method for steel, characterized in that the vertical downward component of the molten steel flow velocity at a position of 20 mm from the interface between the solidified shell and the molten steel is controlled to be uniformly 5 cm / s or more and 50 cm / s or less in the casting width direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1730396A JPH09206896A (en) | 1996-02-02 | 1996-02-02 | Electromagnetic stirring device in die, and continuous casting method of steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1730396A JPH09206896A (en) | 1996-02-02 | 1996-02-02 | Electromagnetic stirring device in die, and continuous casting method of steel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09206896A true JPH09206896A (en) | 1997-08-12 |
Family
ID=11940248
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1730396A Withdrawn JPH09206896A (en) | 1996-02-02 | 1996-02-02 | Electromagnetic stirring device in die, and continuous casting method of steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09206896A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010240687A (en) * | 2009-04-06 | 2010-10-28 | Nippon Steel Corp | Method for controlling flow of molten steel in casting mold in continuous casting equipment |
| CN104815972A (en) * | 2015-04-24 | 2015-08-05 | 北京首钢国际工程技术有限公司 | Multi-strand, synchronous and online automatic position regulating device for end electromagnetic stirrer |
-
1996
- 1996-02-02 JP JP1730396A patent/JPH09206896A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010240687A (en) * | 2009-04-06 | 2010-10-28 | Nippon Steel Corp | Method for controlling flow of molten steel in casting mold in continuous casting equipment |
| CN104815972A (en) * | 2015-04-24 | 2015-08-05 | 北京首钢国际工程技术有限公司 | Multi-strand, synchronous and online automatic position regulating device for end electromagnetic stirrer |
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