JP2554105B2 - Method for preventing blockage of immersion nozzle in continuous casting - Google Patents

Method for preventing blockage of immersion nozzle in continuous casting

Info

Publication number
JP2554105B2
JP2554105B2 JP62257333A JP25733387A JP2554105B2 JP 2554105 B2 JP2554105 B2 JP 2554105B2 JP 62257333 A JP62257333 A JP 62257333A JP 25733387 A JP25733387 A JP 25733387A JP 2554105 B2 JP2554105 B2 JP 2554105B2
Authority
JP
Japan
Prior art keywords
gas
nozzle
molten steel
continuous casting
bubbles
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.)
Expired - Fee Related
Application number
JP62257333A
Other languages
Japanese (ja)
Other versions
JPH0199760A (en
Inventor
徹也 藤井
宰 鈴木
誠二 渡辺
英就 北岡
明彦 難波
敏和 桜谷
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Steel Corp
Original Assignee
Kawasaki Steel Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kawasaki Steel Corp filed Critical Kawasaki Steel Corp
Priority to JP62257333A priority Critical patent/JP2554105B2/en
Publication of JPH0199760A publication Critical patent/JPH0199760A/en
Application granted granted Critical
Publication of JP2554105B2 publication Critical patent/JP2554105B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D41/00Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
    • B22D41/50Pouring-nozzles
    • B22D41/58Pouring-nozzles with gas injecting means

Description

【発明の詳細な説明】 <産業上の利用分野> 本発明は、従来から連続鋳造のイマージョンノズルに
ガスを吹き込みノズル閉塞防止を図っているが、このと
き生ずる鋳片への介在物混入、すなわち製品の品質欠陥
を防止するためになされたものである。
DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention has hitherto attempted to prevent gas from being blown into an immersion nozzle of continuous casting to prevent clogging of the nozzle. This is done to prevent product quality defects.

<従来の技術> 溶鋼の連続鋳造において、タンディッシュと鋳型との
間に注入流の流路をなすイマージョンノズルが使用さ
れ、このノズルの閉塞を防止するために、ガスをノズル
内に吹き込む方法が採用されているが、この際のガスが
鋳型内で浴面上に完全に浮上しなくその一部が介在物を
伴って鋳片中にトラップされ、製品の品質欠陥となる。
ノズルには第1図に示すような装置が使用されるが、吹
き込みガスとしては溶鋼への溶解がほとんど無視できる
アルゴンガスや溶解速度の小さい窒素ガスが主に用いら
れている。本方法は、ノズル内を流れるアルゴンガス
(以下Arと略記)がノズル内壁を洗浄することにより、
ノズル内壁へのアルミナ(以下Al2O3と略記)の付着や
溶鋼の凝固付着を防止し、ノズルの鋳造中の閉塞を防止
する上で極めて効果的な方法である。本方法はアルミニ
ウム(以下Alと略記)で脱酸された、換言すれば実質的
にAlを含有する鋼の連続鋳造を安定して長時間行うのに
優れた技術であり、広く工業的に用いられている。本方
法ではノズル内に吹き込まれたArあるいはN2ガスは、そ
の大部分がノズル内を溶鋼と共に流下し、気泡として鋳
型内に流入する。これらの気泡は、鋳型内の鋼浴上に浮
上することとなる。しかし、これらの気泡のうちで極く
一部は鋼浴上に浮上する機会をなくして、注入流ととも
に鋳型内の鋼浴中の深くまで侵入し、鋳型あるいはそれ
以後の領域で凝固中の鋳片の凝固殻にトラップされるこ
とがある。鋳造後の鋳片を破断して調査するとこれらの
トラップされた気泡は、鋳片の表面近傍に存在するが、
さらに詳細に観察すると、これらの気泡はAl2O3などの
介在物を伴い、その後の圧延過程を経て冷延鋼板の製品
となってもその痕跡をとどめて、製品の欠陥となる。
<Prior Art> In continuous casting of molten steel, an immersion nozzle that forms a flow path of an injection flow between a tundish and a mold is used, and a method of blowing gas into the nozzle is used to prevent clogging of the nozzle. Although adopted, the gas at this time does not completely float above the bath surface in the mold and a part of it is trapped in the slab along with inclusions, resulting in product quality defects.
The apparatus shown in FIG. 1 is used for the nozzle, and as the blowing gas, argon gas whose melting in molten steel is almost negligible and nitrogen gas having a low melting rate are mainly used. This method uses argon gas (hereinafter abbreviated as Ar) flowing in the nozzle to clean the inner wall of the nozzle.
This is an extremely effective method for preventing the adhesion of alumina (hereinafter abbreviated as Al 2 O 3 ) and the solidification adhesion of molten steel to the inner wall of the nozzle, and preventing clogging of the nozzle during casting. This method is an excellent technique for stably and continuously performing continuous casting of steel deoxidized with aluminum (hereinafter abbreviated as Al), in other words, substantially containing Al, and is widely used industrially. Has been. In this method, most of Ar or N 2 gas blown into the nozzle flows down together with the molten steel in the nozzle and flows into the mold as bubbles. These bubbles will float above the steel bath in the mold. However, only a small part of these bubbles loses the opportunity to float above the steel bath, penetrates deeply into the steel bath in the mold together with the injection flow, and casts during solidification in the mold or in the region thereafter. May be trapped in a piece of solidified shell. These trapped bubbles are found near the surface of the slab when the slab after casting is broken and investigated.
When observed in more detail, these bubbles are accompanied by inclusions such as Al 2 O 3 and, even if they become a product of a cold-rolled steel sheet through the subsequent rolling process, the traces remain and become a defect of the product.

以上の気泡の鋳片へのトラップの度合いは、鋳型への
注入流の流入様式や鋳造速度に大きく影響され、注入流
の流動様式を改善すべくノズル先端部の形状変更などの
最適化が行われている。しかし、生産性の向上を目指し
て鋳造速度を増大すると、気泡の鋳片へのトラップされ
る量が増大し、問題は完全には解決されていない。
The degree of trapping of bubbles in the slab as described above is greatly influenced by the inflow mode of the injection flow into the mold and the casting speed, and optimization is performed by changing the shape of the nozzle tip to improve the flow mode of the injection flow. It is being appreciated. However, when the casting speed is increased to improve the productivity, the amount of bubbles trapped in the slab increases, and the problem has not been completely solved.

<発明が解決しようとする問題点> 本発明は、従来の方法によると前述のとおり鋳片の凝
固殻に介在物を伴った気泡がトラップされて製品に表面
欠陥が生じ易いという欠点があったので、これらの欠点
を克服し、製品の表面欠陥を防止できるイマージョンノ
ズルの閉塞防止方法を提供するためになされたものであ
る。
<Problems to be Solved by the Invention> According to the conventional method, the present invention has a drawback that air bubbles accompanied by inclusions are trapped in the solidified shell of the slab as described above and a surface defect is likely to occur in the product. Therefore, it is an object of the present invention to overcome these drawbacks and to provide a method for preventing blockage of an immersion nozzle that can prevent surface defects of products.

<問題点を解決するための手段> 本発明は、鋼浴の深さが3m以上といった大型の取鍋の
底部から、種々のガスを溶鋼中に吹き込んだ場合の浴面
の観察結果に基づいて生まれたものである。すなわち従
来用いられていたArガスやN2ガスを溶鋼中に底部から吹
き込むと浴中を浮上し、浴面に到達し大気中に放散され
る現象が観察されるが、H2ガス、COガスあるいはC3H8
どの炭化水素ガスを溶鋼中に吹き込んでも浴面への浮上
は観察されず浴中の浮上過程において浴中に吸収されて
しまっているという現象に基づいて本発明はなされたも
のである。
<Means for Solving Problems> The present invention is based on an observation result of a bath surface when various gases are blown into molten steel from the bottom of a large ladle having a steel bath depth of 3 m or more. It was born. That is, when Ar gas or N 2 gas that has been conventionally used is blown into the molten steel from the bottom, it floats in the bath, and it is observed that it reaches the bath surface and is diffused into the atmosphere, but H 2 gas and CO gas Alternatively, the present invention has been made based on the phenomenon that even if a hydrocarbon gas such as C 3 H 8 is blown into molten steel, levitation to the bath surface is not observed and that it is absorbed in the bath during the levitation process in the bath. It is a thing.

本発明は、1.6m/分以上の高速連続鋳造のタンディッ
シュと鋳型との間のイマージョンノズル内に還元性かつ
可溶性ガスを吹き込み、該ノズルの閉塞防止と凝固殻に
トラップする介在物を伴った気泡を低減する方法であっ
て、該ガスとしてH2ガス、COガスあるいは炭化水素ガス
の可溶性ガスのみを、単独あるいは混合ガスとして吹き
込むことを特徴とする連続鋳造のイマージョンノズルの
閉塞防止方法、である。
The present invention blows a reducing and soluble gas into the immersion nozzle between the tundish and the mold of the high speed continuous casting of 1.6 m / min or more, and involves inclusions that prevent clogging of the nozzle and trap in the solidified shell. a method for reducing bubbles, H 2 gas as the gas, the only soluble gases CO gas or hydrocarbon gas, alone or blockage preventing method of continuous casting immersion nozzle, wherein the blowing a mixed gas in, is there.

<発明をなすに至った経過と作用> H2ガス、COガスあるいはC3H8などの炭化水素ガスはC,
O,Hの元素からなるため、溶鋼への溶解度と溶解速度が
大きく、比較的短時間で溶鋼中に下記の反応で溶解す
る。
<Processes and actions leading to invention> H 2 gas, CO gas or hydrocarbon gas such as C 3 H 8 is C,
Since it consists of O and H elements, it has a high solubility in molten steel and a high dissolution rate, and dissolves in molten steel in the following reaction in a relatively short time.

H2→2 CO→ C3H8→3+8 Al脱酸された溶鋼や、通常の水素濃度5ppm以下の溶鋼
ではこれらの反応が進行することは熱力学的にも合理的
である。
H 2 → 2 H CO → C + O C 3 H 8 → 3 C + 8 H Al It is also rational thermodynamically that these reactions proceed in deoxidized molten steel and ordinary molten steel with a hydrogen concentration of 5 ppm or less. Target.

以上の結果に基づき第1図に示す装置において、ノズ
ル閉塞防止用のガスとしてC,O,Hの元素の組み合せから
なるH2ガスやCOガスを用いた実験を行った。鋳造中の鋳
型内の浴面を観察すると、浴面上に浮上するガス気泡の
量は、従来のArガスやN2ガスの場合と比較しては大幅に
減少し、吹き込み量に対して極くわずかの量が浮上する
のみで、他の大部分のガスは、ノズル内の流下中あるい
はノズルから鋳型内に流入して浴中を浮上する間に溶鋼
中に溶解・吸収されることによるものと考えられた。以
上の結果は、鋳型内の浴中に流入した気泡のうち、浴上
への浮上の機会をなくして、鋳型内の浴中深くまで巻き
込まれた気泡も、上述と同様に溶鋼中に溶解・吸収され
るので、鋳片にトラップされる気泡が大幅に減少するも
のと考えられ、後述のようにトラップされた気泡に基づ
く製品欠陥が大幅に減少した。
Based on the above results, an experiment was conducted in the apparatus shown in FIG. 1 using H 2 gas or CO gas, which is a combination of C, O and H elements, as a gas for preventing nozzle clogging. When observing the bath surface in the casting mold during casting, the amount of gas bubbles floating on the bath surface is significantly reduced compared to the conventional Ar gas and N 2 gas, and it is extremely Only a small amount floats, and most of the other gases are dissolved and absorbed in the molten steel while flowing down in the nozzle or flowing from the nozzle into the mold and floating in the bath. It was considered. The above results indicate that among the bubbles that have flowed into the bath in the mold, the opportunity to float above the bath is eliminated, and the bubbles that are deeply caught in the bath in the mold also dissolve in the molten steel as described above. It is considered that the air bubbles trapped in the slab are significantly reduced as they are absorbed, and the product defects due to the trapped air bubbles are significantly reduced as described later.

ところで、C,O,Hの元素の組み合せからなるH2ガス、C
Oガスあるいは炭化水素ガスの溶解が非常に速く、吹込
みと同時に瞬時に生じるのであればガスを吹き込まない
のと同じこととなり、ノズル閉塞の防止効果が発揮され
ないこととなるが、ノズル閉塞の防止効果について、従
来のArガス法と比較するとArガスよりも少し多いガス流
量を用いるとC,O,Hの元素の組み合せからなるH2ガスやC
Oガスでも十分に閉塞防止効果のあることが判明した。
このことは、ノズル内の溶鋼は毎秒1〜3mの速度で下方
に流れているのでこの流れに乗って気泡も下方に流れる
ので、ノズル内での気泡の滞在時間が0.5秒以下と短
く、大部分の気泡は溶解することなくノズル閉塞防止効
果を発揮し、ノズルから鋳型の溶鋼中に流入し、浴中の
浮上過程で溶鋼中に溶解するものと考えられる。
By the way, H 2 gas consisting of a combination of C, O and H elements, C
If the dissolution of O gas or hydrocarbon gas is very fast and occurs instantaneously at the same time as the blowing, it is the same as not blowing the gas, and the effect of preventing nozzle clogging will not be exhibited, but the prevention of nozzle clogging will be prevented. Regarding the effect, when a gas flow rate slightly higher than Ar gas is used as compared with the conventional Ar gas method, H 2 gas and C consisting of a combination of C, O, and H elements are used.
It was found that even O gas had a sufficient blocking prevention effect.
This is because the molten steel in the nozzle flows downward at a rate of 1 to 3 m / s, and the bubbles also flow downward along with this flow, so the stay time of the bubbles in the nozzle is as short as 0.5 seconds or less, which is large. It is considered that the bubbles in the part exert the effect of preventing nozzle clogging without melting, flow from the nozzle into the molten steel of the mold, and dissolve in the molten steel during the floating process in the bath.

<実施例> 以下に実施例について説明する。<Examples> Examples will be described below.

2ストランドのスラブ連鋳機において内径が70mmのア
ルミナグラファイト製でノズル出口の水平線となす角が
30度の逆Y型状イマージョンノズルを用い、260mm×130
0mmの断面の2基の鋳型に低炭素アルミキルド鋼を1基
の鋳型当り4ton/min(1.69m/分)の速度で注入した。こ
の条件で1本のノズルには、上部から溶鋼への溶解度が
24ppmであるH2ガスを10〜30N/minの速度で吹き込みも
う一方の鋳型用のノズルには従来法による溶鋼への溶解
度が実質的でないArガスを10〜20N/minの速度で吹き
込みノズル閉塞の防止を図った。この条件で270tonの溶
鋼を保持する取鍋内の溶鋼を5鍋連続して注入した。溶
鋼での溶解度と溶解速度が大きいH元素からなるH2ガス
吹きのノズルを用いるストランドとArガス吹きのノズル
を用いるストランドともに、ノズル閉塞は生じず鋳造速
度を所定値に維持した安定した鋳造が可能であった。ま
た、鋳造終了後、両方のノズルを回収して内壁を観察し
たがAl2O3の付着状況は同一で、H2ガスとArガスの差は
認められなかった。さらにこれらの鋳造された鋳片を熱
間圧延と冷間圧延をして0.7mm厚さの鋼板製品を得た
が、トラップされた気泡に基づく製品の表面欠陥の発生
率は、溶鋼への溶解度と溶解速度が大きいH元素からな
るH2ガス使用ノズルを用いたストランドの鋳片で0.24
%、Arガス使用ノズルを用いたストランドの鋳片で0.76
%であり、本発明の溶鋼への溶解度と溶解速度が大きい
H元素からなるH2ガスを用いると、約1/3に減少するこ
とが明らかである。
In a two-strand slab continuous caster, the inner angle is 70 mm and it is made of alumina graphite.
Using a reverse Y-shaped immersion nozzle of 30 degrees, 260 mm x 130
Low carbon aluminum killed steel was injected into two molds having a cross section of 0 mm at a rate of 4 ton / min (1.69 m / min) per mold. Under this condition, one nozzle has a solubility in molten steel from the top.
24 ppm H 2 gas is blown at a rate of 10 to 30 N / min, and the other mold nozzle is blown with Ar gas at a rate of 10 to 20 N / min, whose solubility in molten steel is not substantial by the conventional method. To prevent this. Under this condition, 5 pots of molten steel in a ladle holding 270 tons of molten steel were continuously poured. Both the strand using the H 2 gas blowing nozzle and the strand using the Ar gas blowing nozzle, which consist of H element having a high solubility and a high melting rate in molten steel, do not cause nozzle clogging and can achieve stable casting with the casting speed maintained at a predetermined value. It was possible. Further, after casting, both nozzles were collected and the inner wall was observed, but the adhesion state of Al 2 O 3 was the same, and no difference between H 2 gas and Ar gas was observed. Furthermore, these cast slabs were hot-rolled and cold-rolled to obtain steel plate products with a thickness of 0.7 mm.The occurrence rate of surface defects in the products due to trapped bubbles was determined by the solubility in molten steel. 0.24 in strand slab using H 2 gas nozzle that consists of H element with high dissolution rate
%, 0.76 for strand slab with Ar gas nozzle
%, And it is clear that the use of H 2 gas composed of H element having a high solubility in molten steel and a high dissolution rate according to the present invention reduces it to about 1/3.

また、水素ガスをノズルに吹き込むと、溶鋼の水素濃
度が上昇することが懸念されるが、本実施例の場合、Ar
ガス使用と比較して水素濃度は0.5ppm以下の増加量であ
り、冷延鋼板の品質に影響するレベルではないことが明
らかとなった。この結果は、使用した水素ガスが溶鋼中
に全量吸収されたとして算出される水素濃度上昇量とほ
ぼ一致する。
Further, when hydrogen gas is blown into the nozzle, it is feared that the hydrogen concentration of the molten steel will increase.
It was clarified that the hydrogen concentration increased by 0.5 ppm or less compared to the case of using gas, which was not a level that affected the quality of cold-rolled steel sheet. This result almost coincides with the hydrogen concentration increase amount calculated as the total amount of the hydrogen gas used was absorbed in the molten steel.

同様に、Arガスと脱酸された溶鋼への溶解度が非常に
大きいCとO元素からなるCOガスとの比較実験を行っ
た。この場合にもノズルの閉塞は、COガスノズル,Arガ
スノズルともに皆無であり、COガスがArガスと同等のノ
ズル閉塞防止効果のあることが明らかとなった。また、
同様に0.6mm厚さの冷延鋼板の品質を調査したが、Cと
O元素からなるCOガス使用ノズルを用いたストランドの
鋳片の製品では、Arガスのそれと比較して、表面欠陥の
発生率が約1/3となった。この場合にはCOガスは炭素と
酸素に分解して吸収され、COガスを用いると鋳片の炭素
と酸素濃度が上昇することが予想されるが、分析結果に
よると炭素濃度400〜600ppmの鋳片において炭素の濃度
増加は実質的に認められなかった。酸素濃度は、鋳片で
17〜26ppmであったが、Arノズル使用ストランドと比較
して1〜2ppmの増加であり、実質的な濃度増加とは認め
られない程度であった。この値についても、使用したCO
ガスが全量吸収されたとして算出される炭素と酸素の濃
度増加量が約3ppmと推算されるので、使用したガスの全
量が溶解するわけではないことを考えると、炭素と酸素
の実質的な濃度増加は生じないことが明らかである。
Similarly, a comparative experiment was conducted between Ar gas and CO gas consisting of C and O elements, which has a very high solubility in deoxidized molten steel. In this case as well, there was no nozzle clogging in both the CO gas nozzle and the Ar gas nozzle, and it was clarified that CO gas has the same nozzle clogging prevention effect as Ar gas. Also,
Similarly, the quality of a 0.6 mm thick cold rolled steel sheet was investigated, and in the product of strand slab using a nozzle using CO gas consisting of C and O elements, surface defects were generated compared with those of Ar gas. The rate became about 1/3. In this case, CO gas is decomposed into carbon and oxygen and absorbed, and it is expected that the concentration of carbon and oxygen in the slab will increase when CO gas is used. Substantially no increase in carbon concentration was observed in the strips. Oxygen concentration in the slab
Although it was 17 to 26 ppm, it was an increase of 1 to 2 ppm as compared with the strand using the Ar nozzle, and it was not recognized as a substantial increase in concentration. The CO used for this value as well
It is estimated that the amount of carbon and oxygen concentration increase calculated as if the total amount of gas was absorbed is about 3 ppm, so considering that not all of the gas used dissolves, the actual concentration of carbon and oxygen It is clear that no increase occurs.

以上の説明は、溶鋼への溶解度と溶解速度が大きいH
元素からなるH2ガスと溶鋼への溶解度が非常に大きいC
とO元素からなるCOガスを例にして説明したが、その
他、溶鋼への溶解度が大きく、なおかつ溶解速度が大き
いCとH元素からなるC3H8などの炭化水素系ガスなども
使用可能であり、またこれらの可溶性ガスの混合したも
のの使用も可能であり、本発明に使用される可溶性ガス
はCOガスとH2ガスに限定されるものではない。
The above explanation is based on H, which has a high solubility in molten steel and a high dissolution rate.
C which has very high solubility in H 2 gas consisting of elements and molten steel
Although the explanation has been made by taking the CO gas consisting of the elements O and O as an example, a hydrocarbon gas such as C 3 H 8 consisting of C and H elements, which has a high solubility in molten steel and a high dissolution rate, can also be used. It is also possible to use a mixture of these soluble gases, and the soluble gas used in the present invention is not limited to CO gas and H 2 gas.

また、可溶性ガスの吹込みについて、ノズル部に吹き
込む方法について説明したが、本発明はこれに限定され
るものでなく、可溶性ガスをノズル入口より上方部から
溶解流とともにノズル部に流入させる方法も適用可能で
ある。
Further, regarding the blowing of the soluble gas, the method of blowing into the nozzle portion has been described, but the present invention is not limited to this, and a method of causing the soluble gas to flow into the nozzle portion from above the nozzle inlet together with the dissolved flow is also possible. Applicable.

<発明の効果> 本発明によると、イマージョンノズル閉塞の防止が従
来法のArガス又はN2ガス使用の場合と同じ程度にでき、
さらに従来法では完全な防止が不可能であった凝固殻に
トラップされて鋳片に入り込むガス気泡によって発生し
ていた製品の表面欠陥が防止できた。
<Effects of the Invention> According to the present invention, the prevention of immersion nozzle blockage can be made to the same extent as in the case of using Ar gas or N 2 gas in the conventional method,
Furthermore, it was possible to prevent the surface defects of the product that were generated by gas bubbles trapped in the solidified shell and entering the slab, which could not be completely prevented by the conventional method.

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

第1図は、本発明を説明するための装置の断面図であ
る。 1……タンディッシュ、2……溶鋼、 3……イマージョンノズル、4……ガス配管、 5……鋳型、6……凝固殻。
FIG. 1 is a cross-sectional view of an apparatus for explaining the present invention. 1 ... Tundish, 2 ... Molten steel, 3 ... Immersion nozzle, 4 ... Gas pipe, 5 ... Mold, 6 ... Solidified shell.

───────────────────────────────────────────────────── フロントページの続き (72)発明者 渡辺 誠二 千葉県千葉市川崎町1番地 川崎製鉄株 式会社技術研究本部内 (72)発明者 北岡 英就 千葉県千葉市川崎町1番地 川崎製鉄株 式会社技術研究本部内 (72)発明者 難波 明彦 千葉県千葉市川崎町1番地 川崎製鉄株 式会社技術研究本部内 (72)発明者 桜谷 敏和 千葉県千葉市川崎町1番地 川崎製鉄株 式会社技術研究本部内 (56)参考文献 特開 昭62−38747(JP,A) ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiji Watanabe 1 Kawasaki-cho, Chiba City, Chiba Prefecture Kawasaki Steel Co., Ltd. Technical Research Division (72) Inventor Ei Kitaoka 1 Kawasaki-cho, Chiba City Chiba Prefecture Kawasaki Steel Co., Ltd. Shiki Company Technology Research Headquarters (72) Inventor Akihiko Namba 1 Kawasaki-cho, Chiba City, Chiba Prefecture Kawasaki Steel Co., Ltd.Chemical Company Technology Research Headquarters (72) Inventor Toshikazu Sakuraya 1 Kawasaki-cho, Chiba City Kawasaki Steel Co., Ltd. Technical Research Division (56) References JP-A-62-38747 (JP, A)

Claims (1)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】1.6m/分以上の高速連続鋳造のタンディッ
シュと鋳型との間のイマージョンノズル内に還元性かつ
可溶性ガスのみを吹き込み、該ノズルの閉塞防止と凝固
殻にトラップする介在物を伴った気泡を低減する方法で
あって、該ガスとしてH2ガス、COガスあるいは炭化水素
ガスを、単独あるいは混合ガスとして吹き込むことを特
徴とする連続鋳造のイマージョンノズルの閉塞防止方
法。
1. A reducible and soluble gas is blown into an immersion nozzle between a tundish and a mold for high speed continuous casting of 1.6 m / min or more to prevent clogging of the nozzle and to prevent inclusions trapped in a solidified shell. A method for reducing entrained bubbles, which comprises blowing H 2 gas, CO gas or hydrocarbon gas as the gas alone or as a mixed gas, to prevent clogging of an immersion nozzle in continuous casting.
JP62257333A 1987-10-14 1987-10-14 Method for preventing blockage of immersion nozzle in continuous casting Expired - Fee Related JP2554105B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP62257333A JP2554105B2 (en) 1987-10-14 1987-10-14 Method for preventing blockage of immersion nozzle in continuous casting

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP62257333A JP2554105B2 (en) 1987-10-14 1987-10-14 Method for preventing blockage of immersion nozzle in continuous casting

Publications (2)

Publication Number Publication Date
JPH0199760A JPH0199760A (en) 1989-04-18
JP2554105B2 true JP2554105B2 (en) 1996-11-13

Family

ID=17304904

Family Applications (1)

Application Number Title Priority Date Filing Date
JP62257333A Expired - Fee Related JP2554105B2 (en) 1987-10-14 1987-10-14 Method for preventing blockage of immersion nozzle in continuous casting

Country Status (1)

Country Link
JP (1) JP2554105B2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020006407A (en) * 2018-07-09 2020-01-16 日本製鉄株式会社 Continuous casting facility and continuous casting method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6238747A (en) * 1985-08-12 1987-02-19 Kawasaki Steel Corp Continuous casting method for slab for thin cold rolled sheet of dead soft steel without blister defect in annealing stage

Also Published As

Publication number Publication date
JPH0199760A (en) 1989-04-18

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