JPH08229670A - Cleaning method of molten metal to remove bubble and impurities and device therefor - Google Patents
Cleaning method of molten metal to remove bubble and impurities and device thereforInfo
- Publication number
- JPH08229670A JPH08229670A JP3637995A JP3637995A JPH08229670A JP H08229670 A JPH08229670 A JP H08229670A JP 3637995 A JP3637995 A JP 3637995A JP 3637995 A JP3637995 A JP 3637995A JP H08229670 A JPH08229670 A JP H08229670A
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- JP
- Japan
- Prior art keywords
- molten metal
- bubbles
- cylinder
- inclusions
- radius
- 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)
- Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Furnace Charging Or Discharging (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は金属の製造において薄板
製品、厚板製品、条鋼製品等の製品欠陥につながる介在
物および気泡の除去に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the removal of inclusions and bubbles that lead to product defects such as thin plate products, thick plate products and strip products in the production of metals.
【0002】[0002]
【従来の技術】近年、自動車や家電用薄板材および海洋
構造物、貯槽、石油およびガス運搬用鋼管、高張力線材
などの表面や内質の欠陥に対する要求は厳しさを増して
いる。これらの欠陥は、鋳片の表面気泡、内部気泡、内
部割れ、中心偏析、介在物等に起因して発生する。この
中で介在物は薄板の表面疵や、厚板の内部欠陥および線
材では圧延時の断線などの原因となる。2. Description of the Related Art In recent years, demands for surface and internal defects of thin plate materials and marine structures for automobiles and home appliances, storage tanks, steel pipes for transporting oil and gas, high-strength wire rods and the like have become more severe. These defects occur due to surface bubbles, internal bubbles, internal cracks, center segregation, inclusions, etc. of the cast slab. Among these, inclusions cause surface defects on thin plates, internal defects in thick plates, and wire breaks in wire rods.
【0003】一方操業の観点から見ると、脱酸生成物が
アルミナなどの場合、鍋ノズルや浸漬ノズル内面にアル
ミナクラスターを含有した地金等が成長してノズル閉塞
が発生し鋳造が困難に至る。このようなノズル閉塞を回
避するため、浸漬ノズル内への不活性ガスの吹込みが一
般に行なわれている。このノズル内不活性ガスの吹込み
はノズル閉塞の防止対策として有効であるが、しかし吹
込んだ不活性ガスがモールド内に巻込まれ、凝固シェル
に捕捉される。この鋳片皮下に捕捉された気泡は製品の
表面欠陥の原因となり、スカーフィングによる鋳片表面
の溶削による手入れが不可欠になっている。On the other hand, from the viewpoint of operation, when the deoxidation product is alumina or the like, a metal or the like containing alumina clusters grows on the inner surface of the pot nozzle or the dipping nozzle to cause nozzle clogging, which makes casting difficult. . In order to avoid such nozzle clogging, blowing of an inert gas into the immersion nozzle is generally performed. The blowing of the inert gas in the nozzle is effective as a measure for preventing the nozzle clogging, but the blown inert gas is caught in the mold and captured by the solidified shell. The air bubbles trapped under the slab of the slab cause surface defects of the product, and it is indispensable to clean the surface of the slab by scarfing.
【0004】また極低炭素鋼では捕捉された気泡が製品
のふくれ疵の原因となるため、材料とプロセスVol.4(19
91),P1290に述べられている例のごとく、これらの対策
として、連鋳機に垂直部を設けることが有効であること
が良く知られている。しかしながら連鋳機に垂直部があ
っても、鋳片肌直下の気泡巻き込みに起因した表面欠陥
の完全な防止が実現しておらず、単位時間当たりの鋳造
量が多いほどこの欠陥はひどくなり、鋳片表面の溶削に
よる手入れが不可欠で、歩留まり落ちの原因となり、物
流を阻害する要因になっている。Also, in ultra-low carbon steel, trapped air bubbles cause blistering defects in the product, so materials and processes Vol.
91), P1290, it is well known that it is effective to provide a continuous casting machine with a vertical portion as a countermeasure against these problems. However, even if there is a vertical portion in the continuous casting machine, complete prevention of surface defects due to air bubble entrapment just below the surface of the slab has not been realized, and the larger the casting amount per unit time, the more severe this defect becomes. It is indispensable to perform smelting on the surface of the slab, which causes yield loss and hinders physical distribution.
【0005】また連鋳機に垂直部を設けるのは設備の重
装備化で、今後さらに連鋳機の生産性を増大して、設備
の簡便化を実現するには、凝固工程へ介在物、気泡が侵
入しないコンパクトな方法の確立が必要である。Further, it is necessary to equip the continuous casting machine with a vertical portion because the equipment is heavy equipment. In order to further increase the productivity of the continuous casting machine in the future and to simplify the equipment, inclusions in the solidification process, It is necessary to establish a compact method in which bubbles do not enter.
【0006】[0006]
【発明が解決しようとする課題】従って、介在物や気泡
に起因した製品欠陥や歩留まり落ちを防止するために
は、凝固工程へ介在物も気泡も含まない溶湯を供給する
コンパクトな方法の確立が解決すべき重要な課題であ
る。Therefore, in order to prevent product defects and yield loss due to inclusions and bubbles, it is necessary to establish a compact method for supplying molten metal containing neither inclusions nor bubbles to the solidification process. It is an important issue to be solved.
【0007】[0007]
【課題を解決するための手段】本発明の要旨とするとこ
ろは下記のとうりである。 1).タンディシュとモールドの間で、円筒を通過する
溶湯に回転運動を与えながら、円筒の内壁より不活性ガ
スを吹込み、遠心力により気泡を中心部に集積して、気
泡の集積・浮上により、気泡と介在物を浮上分離する上
で、円筒内を通過する溶湯の通過速度を気泡の上昇速度
より小さくすることを特徴とする、気泡と介在物を除去
する溶湯の清浄化法。The gist of the present invention is as follows. 1). While rotating the molten metal passing through the cylinder between the tundish and the mold, an inert gas is blown from the inner wall of the cylinder, and the bubbles are accumulated in the center by centrifugal force. A method for cleaning molten metal for removing bubbles and inclusions, characterized in that, when floating and separating inclusions and inclusions, the passing speed of the molten metal passing through the cylinder is made smaller than the rising speed of bubbles.
【0008】2).タンディシュとモールドの間で、円
筒を通過する溶湯に回転運動を与えながら、円筒の内壁
より不活性ガスを吹込み、遠心力により気泡を中心部に
集積して、気泡の集積・浮上により、介在物を浮上分離
する上で、円筒の溶湯通過断面積Sと通過溶湯量tの間
に(1)式を成立させることを特徴とする前記1).記
載の気泡と介在物を除去する溶湯の清浄化法。 1>{t/(ρ・S)} ………(1) S:円筒の溶湯通過断面積(m2) t:通過溶湯量(ton
/sec) ρ:溶湯の密度(ton/m3)。2). Between the tundish and the mold, while rotating the molten metal passing through the cylinder, an inert gas is blown from the inner wall of the cylinder, and the bubbles are accumulated in the center by centrifugal force. When the material is floated and separated, the formula (1) is established between the molten metal passage cross-sectional area S of the cylinder and the molten metal passage amount t, 1). A method for cleaning a molten metal for removing bubbles and inclusions as described. 1> {t / (ρ · S)} ………… (1) S: Cylindrical molten metal passage cross section (m 2 ) t: Amount of molten metal passed (ton)
/ sec) ρ: Density of molten metal (ton / m 3 ).
【0009】3).タンディシュとモールドの間で、円
筒を通過する溶湯に回転運動を与えながら、円筒の内壁
より不活性ガスを吹込み、遠心力により気泡を中心部に
集積して、気泡の集積・浮上により、気泡と介在物を浮
上分離する上で、円筒の半径Rと円筒の中心部に挿入し
たストッパーの半径rと通過溶湯量tの間に(2)式を
成立させることを特徴とする前記1).記載の気泡と介
在物を除去する溶湯の清浄化法。 1>{t/[ρ・π・(R2−r2)]} (2) R:ガス吹込み介在物遠心分離装置内半径(m) r:
ストッパー半径(m) t:通過溶湯量(ton/sec) ρ:溶湯の密度(ton/m3)
π:円周率。3). While rotating the molten metal passing through the cylinder between the tundish and the mold, an inert gas is blown from the inner wall of the cylinder, and the bubbles are accumulated in the center by centrifugal force. (1) is characterized in that the equation (2) is established between the radius R of the cylinder, the radius r of the stopper inserted in the center of the cylinder and the amount t of molten metal passing through when the inclusions are floated and separated. A method for cleaning a molten metal for removing bubbles and inclusions as described. 1> {t / [ρπ (R 2 −r 2 )]} (2) R: Gas blown inclusions Centrifuge inside radius (m) r:
Stopper radius (m) t: Amount of molten metal passing (ton / sec) ρ: Density of molten metal (ton / m 3 )
π: pi.
【0010】4).タンディシュとモールドの間で、円
筒を通過する溶湯に回転運動を与えながら、円筒壁より
不活性ガスを吹込み、遠心力により気泡を中心部に集積
して、気泡の集積・浮上により、気泡と介在物を浮上分
離する上で、通過溶湯量tに対して、円筒の溶湯通過断
面積S、および円筒半径R、ストッパー半径rを(1)
式または(2)式が成立するようにした、気泡と介在物
を除去する溶湯の清浄化装置。 1>{t/(ρ・S)} ………(1) 1>{t/[ρ・π・(R2−r2)]}……(2) S:ガス吹込み介在物遠心分離装置断面積(m2) t:通
過溶湯量(ton/sec) ρ:溶湯の密度(ton/m3) R:ガス吹込み介在物遠心
分離装置内半径(m) r:ストッパー半径(m) π:円周率。4). Between the tundish and the mold, whilst imparting rotational movement to the molten metal that passes through the cylinder, an inert gas is blown from the cylinder wall, and the bubbles accumulate in the center due to the centrifugal force. When the inclusions are floated and separated, the molten metal passage cross-sectional area S, the cylinder radius R, and the stopper radius r are (1)
An apparatus for cleaning a molten metal, which removes bubbles and inclusions, such that expression (2) is satisfied. 1> {t / (ρ · S)} ………… (1) 1> {t / [ρ · π · (R 2 −r 2 )]} …… (2) S: Centrifugal separation of gas-blowing inclusions Cross-sectional area of equipment (m 2 ) t: Amount of molten metal passing (ton / sec) ρ: Density of molten metal (ton / m 3 ) R: Radius of gas blowing inclusions inside centrifugal separator (m) r: Radius of stopper (m) π: pi.
【0011】[0011]
【作用、実施例】図1は本発明の気泡・介在物の遠心分
離装置の概略図で、(A)は平面図、(B)は矢視イ−
イ図であり、図2は本装置をタンディシュ11とモール
ド14の間に設置した例の説明図である。溶湯はタンデ
ィシュ11と浸漬ノズル9の間に設置した断面積がSの
円筒15内で、電磁撹拌コイル1により回転運動を与え
ながら、円筒壁に埋め込んだポーラスプラグまたはアル
ミナグラファイトからなるガス吹込み耐火物2により不
活性ガスを吹込む。OPERATION AND EXAMPLES FIG. 1 is a schematic view of a centrifugal separator for air bubbles / inclusions according to the present invention. (A) is a plan view and (B) is an arrow view.
FIG. 2 is an explanatory diagram of an example in which the device is installed between the tundish 11 and the mold 14. In the cylinder 15 having a cross-sectional area S installed between the tundish 11 and the dipping nozzle 9, the molten metal is rotated by the electromagnetic stirring coil 1 and is gas-fired with a porous plug or alumina graphite embedded in the cylindrical wall. Inert gas is blown by the object 2.
【0012】吹込み不活性ガスの背圧や流量は配管3の
途中に取付けた、流量、圧力調整計測装置5で制御し
て、溶湯の排出速度は本装置の下方に設定したスライデ
ィングノズル7の開度で制御する。溶湯の回転速度は電
磁撹拌コイル1の電流値や周波数で制御する。ガス吹き
込み耐火物2から吹込んだ不活性ガスは炉壁における剪
断力と、遠心力場であることから、微細気泡12に分断
・微細化する。この微細気泡12は遠心分離により中心
部に集積し、各気泡は中心部に近づくにつれ接近するた
め、合体・粗大化して、大気泡13となり浮上する。気
泡が炉壁から中心部に移動する間に気泡の表面には介在
物が集積して、介在物は気泡とともに浮上・分離する。The back pressure and flow rate of the blown-in inert gas are controlled by a flow rate and pressure adjusting measuring device 5 installed in the middle of the pipe 3, and the molten metal discharge speed is controlled by a sliding nozzle 7 set below this device. Control by opening. The rotation speed of the molten metal is controlled by the current value and frequency of the electromagnetic stirring coil 1. Since the inert gas blown from the gas-blown refractory 2 is a shearing force on the furnace wall and a centrifugal force field, it is divided into fine bubbles 12 and becomes fine. The fine bubbles 12 are accumulated in the central portion by centrifugal separation, and the respective bubbles approach each other as they approach the central portion, so that they coalesce and coarsen to become large bubbles 13 and float. While the bubbles move from the furnace wall to the center, inclusions accumulate on the surface of the bubbles, and the inclusions float and separate together with the bubbles.
【0013】しかしながら本装置内を単位時間当たりに
通過する溶湯の下降速度が大きい場合、微細気泡12は
溶湯から完全に分離できず、浸漬ノズル9内に巻き込ま
れ、モールド14内に侵入して、凝固界面に捕捉され、
鋳片の表面欠陥等の原因となる。However, when the descending speed of the molten metal passing through the apparatus per unit time is high, the fine bubbles 12 cannot be completely separated from the molten metal, are caught in the dipping nozzle 9 and enter the mold 14. Trapped at the solidification interface,
It causes a surface defect of the cast slab.
【0014】図3は鋳片の表面から、深さ8mmの試料
を採取してX線で透過観察することにより、測定した気
泡の個数と(3)式で計算した装置内を通過する溶湯流
速Uとの関係である。通過溶湯流速Uが1m/sec以上
になった場合、鋳片の肌下気泡は大幅に増大する。従っ
て、鋳片肌下の気泡の数を減らすためには、装置内の溶
湯通過断面4の面積Sを(1)式に示す条件にする必要
がある。FIG. 3 shows the number of bubbles measured and the flow velocity of the molten metal passing through the apparatus calculated by the equation (3) by taking a sample with a depth of 8 mm from the surface of the slab and observing it with X-rays. It is a relationship with U. When the passing molten metal flow velocity U becomes 1 m / sec or more, the bubbles under the skin of the slab significantly increase. Therefore, in order to reduce the number of bubbles under the surface of the slab, it is necessary to set the area S of the molten metal passage section 4 in the apparatus to the condition shown in the equation (1).
【0015】図4は図5に示すごとく、装置内半径(円
筒14の内半径)がRで、半径rのストッパー10で溶
湯流量を制御した例で、この場合も鋳片の肌下気泡は
(4)式で計算した本装置内の溶湯流速Uが1m/sec
以上で増大して、介在物および気泡のモールド内への侵
入を防止して、鋳片の肌下気泡をなくすには(2)式の
条件を満足する必要がある。図6に鋳片の肌下の気泡の
数に及ぼす吹込み不活性ガスの流量の影響を示す。吹込
む不活性ガスの流量を増大しても、鋳片の肌下気泡の数
に及ぼす影響は小さい。As shown in FIG. 5, FIG. 4 shows an example in which the inner radius of the apparatus (the inner radius of the cylinder 14) is R, and the flow rate of the molten metal is controlled by the stopper 10 having the radius r. The molten metal flow velocity U in this device calculated by the equation (4) is 1 m / sec.
It is necessary to satisfy the condition of formula (2) in order to prevent inclusions and bubbles from entering the mold and eliminate bubbles under the skin of the slab by increasing the above. FIG. 6 shows the effect of the flow rate of the blown inert gas on the number of bubbles under the skin of the slab. Even if the flow rate of the inert gas blown in is increased, the influence on the number of bubbles under the skin of the slab is small.
【0016】 1>{t/(ρ・S)} (1) 1>{t/[ρ・π・(R2−r2)]} (2) U={t/(ρ・S)} (3) U={t/[ρ・π・(R2−r2)]} (4) S:ガス吹込み介在物遠心分離装置断面積(m2) t:
注入速度(ton/sec) ρ:溶湯の密度(ton/m3) R:ガス吹込み介在物遠心
分離装置半径(m) r:ストッパー半径(m) π:円周率 U:本装置内通
過溶湯流速(m/sec)。1> {t / (ρ · S)} (1) 1> {t / [ρ · π · (R 2 −r 2 )]} (2) U = {t / (ρ · S)} (3) U = {t / [ρ · π · (R 2 −r 2 )]} (4) S: Gas blown inclusions centrifugal separator cross-sectional area (m 2 ) t:
Injection speed (ton / sec) ρ: Density of molten metal (ton / m 3 ) R: Radius of gas-injection inclusion centrifugal separator (m) r: Radius of stopper (m) π: Circular ratio U: Passing through this device Melt flow rate (m / sec).
【0017】以上のごとく鋳片への気泡の巻き込み防止
には(1)(2)式を満足する装置条件にすれば良いこ
とを知見して本発明を成し遂げた。また図7はアルミナ
グラファイト浸漬ノズルで連々鋳7チャージの極低炭素
鋼を鋳造した場合のノズル閉塞発生頻度を従来法と比較
した結果である。本法によりノズル閉塞の発生を大幅に
低減できる。これは本法により、ノズル閉塞の原因とな
る溶湯中の微細介在物が浸漬ノズルに至る前に効率的に
除去されることによる。As described above, the present invention has been accomplished by finding that it is sufficient to set the apparatus conditions that satisfy the equations (1) and (2) in order to prevent the inclusion of air bubbles in the cast slab. Further, FIG. 7 is a result of comparing the nozzle clogging occurrence frequency in the case of casting ultra-low carbon steel of 7-charge continuous casting with an alumina graphite immersion nozzle, compared with the conventional method. This method can significantly reduce the occurrence of nozzle blockage. This is because the present method efficiently removes fine inclusions in the molten metal that cause nozzle clogging before reaching the immersion nozzle.
【0018】[0018]
【発明の効果】以上のごとく本発明により、気泡のモー
ルド内への侵入の防止とノズル閉塞発生頻度の大幅な低
減が可能になった。その結果、凝固シェルへの気泡の捕
捉に起因した、表面手入れや表面欠陥の大幅な改善と、
鋳造速度の増速や物流改善により生産性の増大が可能と
なった。As described above, according to the present invention, it is possible to prevent air bubbles from entering the mold and significantly reduce the frequency of occurrence of nozzle clogging. As a result, due to the trapping of air bubbles in the solidified shell, surface care and surface defects are greatly improved,
It has become possible to increase productivity by increasing casting speed and improving logistics.
【図1】は本装置の概略を示す図。FIG. 1 is a diagram showing an outline of the present apparatus.
【図2】は本装置の設置方法の概略を示す図。FIG. 2 is a diagram showing an outline of a method for installing this device.
【図3】はX線透過写真で観察した鋳片肌下気泡の数と
本装置内を通過する溶湯速度の関係を示す図。FIG. 3 is a diagram showing the relationship between the number of bubbles under the slab observed in an X-ray transmission photograph and the speed of the molten metal passing through the apparatus.
【図4】はX線透過写真で観察した鋳片肌下気泡の数と
ストッパーで溶湯流量量を制御した場合の溶湯流速の関
係を示す図。FIG. 4 is a diagram showing the relationship between the number of bubbles under the slab observed on an X-ray radiograph and the melt flow rate when the flow rate of the melt is controlled by a stopper.
【図5】はストッパーで溶湯流量を制御した場合の装置
の概略を示す図。FIG. 5 is a diagram showing an outline of an apparatus when a molten metal flow rate is controlled by a stopper.
【図6】はX線透過写真で観察した鋳片の肌下気泡に及
ぼす吹込み不活性ガス量の影響の図。FIG. 6 is a diagram showing the effect of the amount of blown inert gas on the under-skin bubbles of the slab observed by an X-ray transmission photograph.
【図7】は本法の浸漬ノズル閉塞防止効果を示す図(浸
漬ノズル材質はアルミナグラファイト)。FIG. 7 is a view showing the effect of preventing the immersion nozzle from being blocked by this method (the material of the immersion nozzle is alumina graphite).
1:電磁撹拌コイル 2:ガス吹込み耐火物 3:吹込
みArガス 4:溶湯通過断面 5:背圧測定装置
6:不活性ガス吹込み介在物遠心分離部 7:スライデ
ィングノズル 8:中間ノズル 9:浸漬ノズル 1
0:ストッパー11:タンディシュ 12:微細気泡
13:大気泡 14:モールド。1: Electromagnetic stirring coil 2: Refractory gas blown 3: Ar gas blown 4: Molten metal cross section 5: Back pressure measuring device
6: Inert gas blown inclusions centrifugal separator 7: Sliding nozzle 8: Intermediate nozzle 9: Immersion nozzle 1
0: Stopper 11: Tundish 12: Fine bubbles
13: Large bubbles 14: Mold.
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 FI 技術表示箇所 C21C 7/072 C21C 7/072 P F27D 3/15 F27D 3/15 S ─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 6 Identification code Internal reference number FI Technical display location C21C 7/072 C21C 7/072 P F27D 3/15 F27D 3/15 S
Claims (4)
過する溶湯に回転運動を与えながら、円筒の内壁より不
活性ガスを吹込み、遠心力により気泡を中心部に集積し
て、気泡の集積・浮上により、気泡と介在物を浮上分離
する上で、円筒内を通過する溶湯の通過速度を気泡の上
昇速度より小さくすることを特徴とする、気泡と介在物
を除去する溶湯の清浄化法。1. Between the tundish and the mold, while the molten metal passing through the cylinder is being rotated, an inert gas is blown from the inner wall of the cylinder and the bubbles are accumulated in the central portion by centrifugal force to collect the bubbles.・ A method for cleaning molten metal for removing bubbles and inclusions, characterized in that when the bubbles and inclusions are floated and separated by levitation, the passing speed of the molten metal passing through the cylinder is made smaller than the rising speed of the bubbles. .
過する溶湯に回転運動を与えながら、円筒の内壁より不
活性ガスを吹込み、遠心力により気泡を中心部に集積し
て、気泡の集積・浮上により、介在物を浮上分離する上
で、円筒の溶湯通過断面積Sと通過溶湯量tの間に
(1)式を成立させることを特徴とする請求項1記載の
気泡と介在物を除去する溶湯の清浄化法。 1>{t/(ρ・S)} ………(1) S:円筒の溶湯通過断面積(m2) t:通過溶湯量
(ton/sec) ρ:溶湯の密度(ton/m3)2. Between the tundish and the mold, while imparting a rotary motion to the molten metal passing through the cylinder, an inert gas is blown from the inner wall of the cylinder and the bubbles are accumulated in the central portion by centrifugal force to accumulate the bubbles. The bubbles and inclusions according to claim 1, wherein the equation (1) is established between the molten metal passage cross-sectional area S of the cylinder and the molten metal passage amount t when the inclusions are floated and separated by levitation. Method for cleaning molten metal to be removed. 1> {t / (ρ · S)} ………… (1) S: Cross-sectional area of molten metal passage (m 2 ) t: Amount of molten metal passed (ton / sec) ρ: Density of molten metal (ton / m 3 )
過する溶湯に回転運動を与えながら、円筒の内壁より不
活性ガスを吹込み、遠心力により気泡を中心部に集積し
て、気泡の集積・浮上により、気泡と介在物を浮上分離
する上で、円筒の半径Rと円筒の中心部に挿入したスト
ッパーの半径rと通過溶湯量tの間に(2)式を成立さ
せることを特徴とする請求項1記載の気泡と介在物を除
去する溶湯の清浄化法。 1>{t/[ρ・π・(R2−r2)]}………(2) R:ガス吹込み介在物遠心分離装置内半径(m) r:
ストッパー半径(m) t:通過溶湯量(ton/sec) ρ:溶湯の密度(ton/m
3) π:円周率3. Between the tundish and the mold, while imparting rotational motion to the molten metal passing through the cylinder, an inert gas is blown from the inner wall of the cylinder and the bubbles are accumulated in the central portion by centrifugal force to accumulate the bubbles. When levitation separates bubbles and inclusions by levitation, the formula (2) is established between the radius R of the cylinder, the radius r of the stopper inserted in the center of the cylinder, and the amount of passing molten metal t. The method for cleaning a molten metal according to claim 1, wherein the bubbles and inclusions are removed. 1> {t / [ρ · π · (R 2 −r 2 )]} (2) R: Radius of gas-blended inclusions centrifugal separator (m) r:
Stopper radius (m) t: Amount of molten metal passing (ton / sec) ρ: Density of molten metal (ton / m)
3 ) π: Pi
過する溶湯に回転運動を与えながら、円筒壁より不活性
ガスを吹込み、遠心力により気泡を中心部に集積して、
気泡の集積・浮上により、気泡と介在物を浮上分離する
上で、通過溶湯量tに対して、円筒の溶湯通過断面積
S、および円筒半径R、ストッパー半径rを(1)式ま
たは(2)式が成立するようにした、気泡と介在物を除
去する溶湯の清浄化装置。 1>{t/(ρ・S)} ………(1) 1>{t/[ρ・π・(R2−r2)]}……(2) S:ガス吹込み介在物遠心分離装置断面積(m2) t:通
過溶湯量(ton/sec) ρ:溶湯の密度(ton/m3) R:ガス吹込み介在物遠心
分離装置内半径(m) r:ストッパー半径(m) π:円周率4. Between the tundish and the mold, while imparting rotational motion to the molten metal passing through the cylinder, an inert gas is blown from the wall of the cylinder, and bubbles are accumulated in the central portion by centrifugal force,
When the bubbles and inclusions are floated and separated by the accumulation and floating of the bubbles, the molten metal passage cross-sectional area S of the cylinder, the cylindrical radius R, and the stopper radius r are expressed by the formula (1) or (2 ) A molten metal cleaning device that removes bubbles and inclusions so that the equation is satisfied. 1> {t / (ρ · S)} ………… (1) 1> {t / [ρ · π · (R 2 −r 2 )]} …… (2) S: Centrifugal separation of gas-blowing inclusions Equipment cross-sectional area (m 2 ) t: Molten metal flow rate (ton / sec) ρ: Molten metal density (ton / m 3 ) R: Gas blown inclusions Centrifuge inner radius (m) r: Stopper radius (m) π: Pi
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3637995A JPH08229670A (en) | 1995-02-24 | 1995-02-24 | Cleaning method of molten metal to remove bubble and impurities and device therefor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3637995A JPH08229670A (en) | 1995-02-24 | 1995-02-24 | Cleaning method of molten metal to remove bubble and impurities and device therefor |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH08229670A true JPH08229670A (en) | 1996-09-10 |
Family
ID=12468219
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3637995A Withdrawn JPH08229670A (en) | 1995-02-24 | 1995-02-24 | Cleaning method of molten metal to remove bubble and impurities and device therefor |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH08229670A (en) |
Cited By (2)
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JP2017051998A (en) * | 2015-09-11 | 2017-03-16 | 新日鐵住金株式会社 | Continuous casting device of metal and continuous casting method of metal |
CN110290888A (en) * | 2017-02-20 | 2019-09-27 | Abb公司 | For controlling the method and stirring system of magnetic stirrer |
-
1995
- 1995-02-24 JP JP3637995A patent/JPH08229670A/en not_active Withdrawn
Cited By (4)
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---|---|---|---|---|
JP2017051998A (en) * | 2015-09-11 | 2017-03-16 | 新日鐵住金株式会社 | Continuous casting device of metal and continuous casting method of metal |
CN110290888A (en) * | 2017-02-20 | 2019-09-27 | Abb公司 | For controlling the method and stirring system of magnetic stirrer |
US10919088B2 (en) | 2017-02-20 | 2021-02-16 | Abb Schweiz Ag | Method and stirring system for controlling an electromagnetic stirrer |
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A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20020507 |