JPH07113114A - Method of stirring molten metal - Google Patents
Method of stirring molten metalInfo
- Publication number
- JPH07113114A JPH07113114A JP25820593A JP25820593A JPH07113114A JP H07113114 A JPH07113114 A JP H07113114A JP 25820593 A JP25820593 A JP 25820593A JP 25820593 A JP25820593 A JP 25820593A JP H07113114 A JPH07113114 A JP H07113114A
- Authority
- JP
- Japan
- Prior art keywords
- tuyere
- ladle
- molten metal
- stirring
- gas
- 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.)
- Granted
Links
Landscapes
- Manufacture And Refinement Of Metals (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
(57)【要約】
【目的】 溶鋼のガス攪拌の高効率化。
【構成】 取鍋精錬の真空脱ガス処理に際して、偏心距
離Ｘが式(1) を満足する条件下でガス攪拌を行う。
【効果】 [C] を10ppm 以下、[H] を１ppm 以下にまで
低減可能。
(57) [Summary] [Purpose] Improving the gas stirring efficiency of molten steel. [Structure] During the vacuum degassing process of ladle refining, gas stirring is performed under the condition that the eccentric distance X satisfies the formula (1). [Effect] [C] can be reduced to 10ppm or less and [H] to 1ppm or less.
Description
【０００１】[0001]
【産業上の利用分野】本発明は、溶融金属の取鍋精錬を
行う際の溶融金属の攪拌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 a method for stirring molten metal in ladle refining of molten metal.
【０００２】[0002]
【従来の技術】溶融金属として溶鋼を例に挙げて説明す
ると、従来より、溶鋼の取鍋精錬において浸漬管を用い
た減圧精錬装置の攪拌方法としては、すでに各種の方式
のものが提案されている。2. Description of the Related Art Explaining molten steel as an example of molten metal, various methods have been proposed as stirring methods for a depressurization refining apparatus using a dip tube in ladle refining of molten steel. There is.
【０００３】例えば、特開昭63−140029号公報に開示さ
れる方法によれば、浸漬管外周部に電磁気発生装置を設
置し、これによって溶鋼を攪拌するのである。しかし、
このような電磁気による攪拌を行う場合、多大な電力を
消費しなければならず、設備上も膨大な費用が必要とな
り、管理、維持に手間がかかるなどの問題がある。[0003] For example, according to the method disclosed in Japanese Patent Laid-Open No. 63-140029, an electromagnetic generator is installed on the outer peripheral portion of the dip tube, and the molten steel is stirred by this. But,
When performing such electromagnetic stirring, a large amount of electric power must be consumed, a huge amount of equipment is required, and management and maintenance are troublesome.
【０００４】一方、特開平４−59912 号公報にはガス吹
込みによる攪拌方法が開示されおり、これによれば、浸
漬管断面を楕円形とし、取鍋底部に設置するポーラスプ
ラグの位置を浸漬管中心より楕円長軸方向に偏心させて
設置している。しかし、偏心の程度により以下の問題が
生じる。On the other hand, Japanese Patent Application Laid-Open No. 4-59912 discloses a stirring method by blowing gas. According to this method, the dipping pipe has an elliptical cross section and the position of the porous plug installed at the bottom of the ladle is dipped. The center of the pipe is eccentric to the major axis of the ellipse. However, the following problems occur depending on the degree of eccentricity.
【０００５】すなわち、例えば300 mmというように偏心
が少なすぎる場合には、浴の混合が充分に行われず、精
錬効果が大きく低下する。一方、偏心が大きすぎる場合
には、攪拌ガスが浸漬管外へ流出してしまい、浸漬管内
の攪拌力が著しく低下し、また浸漬管外へ流出した攪拌
ガスにより取鍋スラグが溢出するなどの危険が生じる。That is, if the eccentricity is too small, for example, 300 mm, the bath is not sufficiently mixed, and the refining effect is greatly reduced. On the other hand, if the eccentricity is too large, the stirring gas will flow out of the immersion pipe, the stirring force in the immersion pipe will be significantly reduced, and the ladle slag will overflow due to the stirring gas flowing out of the immersion pipe. Danger occurs.
【０００６】同様の攪拌ガスによる攪拌の例としては、
特開平１−156416号公報に示す方法があり、これによれ
ば底吹きポーラスプラグの偏心の程度を一定の範囲内に
限定することにより、効率のよい減圧精錬が可能である
としている。しかしながら、このポーラスプラグの設定
範囲についても以下のような問題があり、限られた装置
条件でしか有効ではない。As an example of stirring with the same stirring gas,
There is a method disclosed in Japanese Patent Laid-Open No. 1-156416, and it is said that efficient depressurization refining can be performed by limiting the degree of eccentricity of the bottom blown porous plug within a certain range. However, the setting range of this porous plug has the following problems and is effective only under limited device conditions.
【０００７】浸漬管中心からの偏心の程度の上限とし
て、 Ｘ／Ｒ≦ 0.33 Ｒ／Ｄ ただし、Ｒ: 浸漬管内径、 Ｄ: 取鍋内径、 Ｘ: 浸漬管投影面中心からのポーラスプラグの偏心 が設定されているが、浸漬管の浸漬深さが浅い場合、プ
ルーム（底吹きガス等の気泡が上昇する際に通過する領
域) の広がりを考慮していないため、浸漬管外への攪拌
ガスの流出の問題は解決できない。As the upper limit of the degree of eccentricity from the center of the immersion tube, X / R ≦ 0.33 R / D, where R: inner diameter of immersion tube, D: inner diameter of ladle, X: eccentricity of porous plug from center of projected surface of immersion tube However, when the immersion depth of the immersion pipe is shallow, the spread of the plume (the region through which bubbles such as bottom-blown gas pass when rising) is not considered, so the stirring gas outside the immersion pipe is not considered. Can not solve the problem of the outflow of.
【０００８】また、下限を Ｘ／Ｒ≧ 0.33 Ｒ／Ｄ− 0.07 としているが、この場合、流れの水平成分が偏心方向と
逆方向にも発生し、相殺されて充分な攪拌が不可能とな
る。なお、この例における具体的偏心量は高々450 mmで
あった。以上のように、従来の方法では効率的な攪拌は
不可能であった。Further, the lower limit is set to X / R ≧ 0.33 R / D-0.07, but in this case, a horizontal component of the flow also occurs in the direction opposite to the eccentric direction, which cancels each other out and sufficient stirring becomes impossible. . The specific amount of eccentricity in this example was 450 mm at most. As described above, efficient stirring cannot be performed by the conventional method.
【０００９】[0009]
【発明が解決しようとする課題】ここに、本発明の目的
は、攪拌ガスによる溶融金属、例えば溶鋼の攪拌効率を
大幅に向上させ、かつ攪拌ガスの浸漬管外への流出を効
果的に防止する方法を提供することである。SUMMARY OF THE INVENTION An object of the present invention is to significantly improve the stirring efficiency of molten metal, for example, molten steel, by stirring gas, and effectively prevent the stirring gas from flowing out of the immersion pipe. Is to provide a way to do.
【００１０】[0010]
【課題を解決するための手段】かかる目的達成のための
手段について、本発明者は、鋭意検討を重ねた結果、攪
拌ガス吹込み用の羽口の位置を適切に設定することによ
り、上記の課題が解決可能であることを知見し、本発明
を完成した。Means for Solving the Problems As a result of earnest studies on the means for achieving the above object, the present inventor has found that by appropriately setting the position of the tuyere for blowing the stirring gas, The present invention has been completed by finding that the problem can be solved.
【００１１】ここに、本発明の要旨とするところは、溶
融金属を収容する取鍋中に浸漬管を浸漬させて、浸漬管
内を減圧にして溶融金属を吸上げ、取鍋下部の浸漬管投
影面下に設置した羽口から攪拌ガスを吹込み溶融金属を
攪拌しながら取鍋精錬を行うに際して、前記羽口の設置
位置の取鍋中心よりの偏心距離Ｘが下記(1) 式の条件を
満たすようにすることを特徴とする、溶融金属の攪拌方
法である。Here, the gist of the present invention is to immerse a dip tube in a ladle containing molten metal, reduce the pressure in the dip tube to suck up the molten metal, and project the dip tube at the bottom of the ladle. When performing ladle refining while stirring the molten metal by injecting stirring gas from the tuyere installed below the surface, the eccentric distance X from the center of the ladle at the tuyere installation position satisfies the condition of the following formula (1). It is a method for stirring molten metal, which is characterized in that it is filled.
【００１２】[0012]
【数１】 [Equation 1]
【００１３】本発明の好適態様によれば、同時に複数の
羽口を設置する場合、取鍋中心と羽口位置を結ぶ線の中
心角αが 120°以内になるように設置すればよい。ま
た、上昇気泡の広がり角度は攪拌ガスの吹込み速度によ
って決まることから、各精錬条件を考慮した場合、換言
すれば、本発明はそれらの条件にもとづいて取鍋精錬を
行う場合の浸漬管の偏心の量、つまり設置位置の決定方
法である。According to a preferred embodiment of the present invention, when a plurality of tuyere are installed at the same time, the tuyere may be installed so that the center angle α of the line connecting the center of the ladle and the tuyere position is within 120 °. Further, since the spread angle of the rising bubbles is determined by the blowing speed of the stirring gas, when considering each refining condition, in other words, the present invention is a dip tube in the case of performing ladle refining based on those conditions. It is a method of determining the amount of eccentricity, that is, the installation position.
【００１４】[0014]
【作用】次に、本発明の作用について添付図面を参照し
ながらさらに詳細に説明する。なお、以下の例にあって
は溶融金属として溶鋼を例にとって説明する。図１は、
本発明の概念図を示すものであり、図中、取鍋10に収容
された溶鋼12中に浸漬管14を浸漬させて、浸漬管内を減
圧にして溶鋼12を吸上げ、取鍋下部の浸漬管投影面下に
羽口16 (位置のみ示す) を設置して、攪拌ガスを吹込み
溶鋼を攪拌しながら取鍋精錬を行う。Next, the operation of the present invention will be described in more detail with reference to the accompanying drawings. In the following example, molten steel will be described as an example of molten metal. Figure 1
It is a conceptual diagram of the present invention, in which the immersion pipe 14 is immersed in the molten steel 12 housed in the ladle 10, the interior of the immersion pipe is decompressed to suck up the molten steel 12, and the lower part of the ladle is immersed. The tuyere 16 (only the position is shown) is installed below the projection surface of the tube, and the ladle refining is performed while blowing the stirring gas and stirring the molten steel.
【００１５】吹込みガスは溶鋼内部を上昇しながら、徐
々に広がる。この広がり角をθとし、浸漬管下端からガ
ス吹込み位置までの深さをｈとしたとき、浸漬管下端の
高さへ到達したガスは、半径ｈ×tan θの広がりをも
つ。すなわち、ガスが浸漬管外へ流出しないためには、
ガス吹込み位置は浸漬管内周よりさらにｈ×tan θ以上
の内側に設置する必要がある。上昇気泡の広がり角は攪
拌ガスと溶融金属の密度比によって変わり、溶鋼の場合
には一般にθは20°程度である。すなわち、ガス吹込み
位置の中心よりの距離Ｘの最大値は浸漬管内径をＤとす
ると、The blown gas gradually spreads while rising inside the molten steel. When the spread angle is θ and the depth from the lower end of the immersion pipe to the gas injection position is h, the gas reaching the height of the lower end of the immersion pipe has a spread of radius h × tan θ. That is, in order for the gas not to flow out of the immersion pipe,
It is necessary to install the gas injection position inside the dip tube more than h × tan θ. The divergence angle of the rising bubbles depends on the density ratio of the stirring gas and the molten metal, and in the case of molten steel, θ is generally about 20 °. That is, the maximum value of the distance X from the center of the gas injection position is D, where D is the inside diameter of the immersion pipe.
【００１６】[0016]
【数２】 [Equation 2]
【００１７】で表されることが分かる。一方、Ｘが小さ
い場合、ガスの広がりが中心を越えると流れの水平成分
が二方向に生じるため、流れが分散して環状流が生じに
くくなる。したがって、水平成分のロスを回避するため
には、少なくともガスが浸漬管下端の高さに達したとき
に中心を越えないことが必要である。よって、この条件
は、It can be seen that On the other hand, when X is small, horizontal components of the flow are generated in two directions when the gas spread exceeds the center, so that the flow is dispersed and an annular flow is less likely to occur. Therefore, in order to avoid loss of horizontal components, it is necessary that at least the gas does not cross the center when it reaches the height of the lower end of the dip tube. Therefore, this condition is
【００１８】[0018]
【数３】 [Equation 3]
【００１９】なお、Ｘの下限値については、さらに望ま
しくは、Regarding the lower limit value of X, more desirably,
【００２０】[0020]
【数４】 [Equation 4]
【００２１】である。これは、後述の実施例においても
示されるとおり、均一混合時間がより一層短縮される範
囲となるからである。以上より、羽口の設置範囲は次の
通り規定される。[0021] This is because the uniform mixing time is further shortened as shown in Examples described later. From the above, the tuyere installation range is defined as follows.
【００２２】[0022]
【数５】 [Equation 5]
【００２３】なお、羽口は底吹きポーラスプラグに限定
する必要はなく、浸漬ランスなどを用いてもよい。ただ
し、ランスの深さｈを取鍋内浴深さの50％以上確保する
ことが望ましい。The tuyere need not be limited to the bottom-blown porous plug, and a dipping lance or the like may be used. However, it is desirable to secure the lance depth h of 50% or more of the bath depth in the ladle.
【００２４】かくして本発明によれば、溶融金属の取鍋
精錬に際して溶融金属のより効果的な攪拌と脱ガス処理
が可能となり、例えば[C] 10ppm 以下、[H] 1ppm以下が
達成される。次に、本発明の作用効果について実施例に
よって具体的に説明する。Thus, according to the present invention, it is possible to more effectively stir and degas the molten metal during ladle refining of the molten metal. For example, [C] 10 ppm or less and [H] 1 ppm or less are achieved. Next, the function and effect of the present invention will be specifically described with reference to examples.
【００２５】[0025]
【実施例】本例では図１に示す装置を使用し、浸漬管内
径2600mm、浸漬管下端からガス吹込み羽口までの深さ12
60mmとして、300 トンの溶鋼の脱ガス実験を行った。こ
こで、浸漬管に接続した真空槽内は脱ガス処理開始より
10分で2.5 Torrまで減圧し、さらに脱ガス処理開始後30
分後に１Torrまで減圧した。また、吹込んだ攪拌ガスは
２ Nm3/minのArガスであった。Example In this example, the apparatus shown in FIG. 1 was used, and the inner diameter of the immersion pipe was 2600 mm, and the depth from the lower end of the immersion pipe to the gas blowing tuyere 12
A degassing experiment was conducted on 300 tons of molten steel with a length of 60 mm. Here, the inside of the vacuum chamber connected to the dip tube is
Depressurize to 2.5 Torr in 10 minutes, and after starting degassing process, 30
After a minute, the pressure was reduced to 1 Torr. The stirring gas blown in was Ar gas at 2 Nm 3 / min.
【００２６】このとき、羽口の偏心距離Ｘを変化させ
て、溶鋼中の[C] 濃度、[H] 濃度の変化を調査した。た
だし、羽口数は１本であった。結果を表１に示す。ま
た、中心からの偏心量Ｘと均一混合時間の関係を図２に
グラフでもって示す。At this time, changes in the [C] concentration and [H] concentration in the molten steel were investigated by changing the eccentric distance X of the tuyere. However, the number of tuyere was one. The results are shown in Table 1. Further, the relationship between the amount of eccentricity X from the center and the uniform mixing time is graphically shown in FIG.
【００２７】[0027]
【表１】 [Table 1]
【００２８】表１に示す結果より、偏心量Ｘが小さすぎ
ると均一混合時間が長く、脱Ｃ、脱Ｈとも不充分であっ
た (比較例１、２、３) 。一方、偏心量Ｘが大きすぎる
と均一混合時間は短くなるが、浸漬管外への攪拌ガスの
流出が生じるため、脱Ｃ、脱Ｈは不充分であった (比較
例４、５) 。これに対し、本発明により偏心量Ｘを適切
な範囲、例えば550 ≦Ｘ≦ 810(mm)とすることにより、
均一混合時間も短く、脱Ｃ、脱Ｈとも充分に行われた。From the results shown in Table 1, when the amount of eccentricity X was too small, the uniform mixing time was long, and de-C and de-H were insufficient (Comparative Examples 1, 2, 3). On the other hand, when the amount of eccentricity X is too large, the uniform mixing time is shortened, but degassing and dehydrogenation are insufficient because stirring gas flows out of the immersion tube (Comparative Examples 4 and 5). On the other hand, according to the present invention, by setting the eccentricity amount X in an appropriate range, for example, 550 ≦ X ≦ 810 (mm),
The uniform mixing time was short, and both C removal and H removal were sufficiently performed.
【００２９】次に、同様の装置において、複数の羽口よ
り合計２ Nm3/minのArを吹込んだ場合の同様の溶鋼の脱
ガス実験の結果を表２に示す。ただし、羽口位置はいず
れも中心からの偏心770 mmであり、取鍋中心と羽口位置
を結ぶ線の中心角αは120 度以内であった。図３に各羽
口の取付位置を図示する。図中２以上の羽口を設けたと
きのαの角度は20度以内に規制する。Next, Table 2 shows the results of a similar degassing experiment of molten steel when a total of 2 Nm 3 / min of Ar was blown from a plurality of tuyere in the same apparatus. However, the tuyere positions were eccentric 770 mm from the center, and the central angle α of the line connecting the center of the ladle and the tuyere position was within 120 degrees. FIG. 3 illustrates the mounting position of each tuyere. The angle of α when two or more tuyere is provided in the figure is regulated within 20 degrees.
【００３０】[0030]
【表２】 [Table 2]
【００３１】このとき、羽口数２本、３本のいずれの場
合にも、中心角 120°以内では脱ガスが充分に行われた
が (実施例４〜７) 、中心角が 120°より大きい場合、
脱ガスが不充分となった (比較例６〜８) 。At this time, degassing was sufficiently carried out within the central angle of 120 ° (Examples 4 to 7) in both cases of two tuyere and three tuyere, but the central angle was larger than 120 °. If
Degassing became insufficient (Comparative Examples 6 to 8).
【００３２】[0032]
【発明の効果】本発明により、浸漬管に溶融金属を吸い
上げる減圧精錬において、装置内の攪拌が充分に行わ
れ、脱ガス能が向上した。EFFECTS OF THE INVENTION According to the present invention, in depressurization refining in which a molten metal is sucked into a dip tube, the inside of the apparatus is sufficiently agitated and the degassing ability is improved.
【図面の簡単な説明】[Brief description of drawings]
【図１】本発明の概念を表す説明図である。FIG. 1 is an explanatory diagram showing the concept of the present invention.
【図２】羽口位置による均一混合時間変化を示すグラフ
である。FIG. 2 is a graph showing changes in uniform mixing time depending on tuyere positions.
【図３】取鍋底部における羽口の取付位置の説明図であ
る。FIG. 3 is an explanatory diagram of a tuyere mounting position at the bottom of the ladle.
Claims (2)
漬させて、浸漬管内を減圧にして溶融金属を吸上げ、取
鍋下部の浸漬管投影面下に設置した羽口から攪拌ガスを
吹込み溶融金属を攪拌しながら取鍋精錬を行うに際し
て、 前記羽口の設置位置の取鍋中心よりの偏心距離Ｘが下記
(1) 式の条件を満たすようにすることを特徴とする、溶
融金属の攪拌方法。 【数１】 1. A dipping tube is immersed in a ladle containing molten metal, the inside of the dipping tube is depressurized to suck up the molten metal, and a stirring gas is supplied from a tuyere installed below the projection surface of the dipping tube at the bottom of the ladle. When ladle refining is carried out while stirring the molten metal, the eccentric distance X from the center of the ladle at the tuyere installation position is as follows.
A method for stirring molten metal, characterized by satisfying the condition of formula (1). [Equation 1]
中心と羽口位置を結ぶ線の中心角が 120°以内になるよ
うに設置することを特徴とする請求項１記載の溶融金属
の攪拌方法。2. The melting according to claim 1, wherein when a plurality of tuyere are installed at the same time, they are installed so that the center angle of the line connecting the center of the ladle and the tuyere position is within 120 °. How to stir metal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25820593A JP2929912B2 (en) | 1993-10-15 | 1993-10-15 | Stirring method of molten metal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25820593A JP2929912B2 (en) | 1993-10-15 | 1993-10-15 | Stirring method of molten metal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07113114A true JPH07113114A (en) | 1995-05-02 |
| JP2929912B2 JP2929912B2 (en) | 1999-08-03 |
Family
ID=17316976
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP25820593A Expired - Lifetime JP2929912B2 (en) | 1993-10-15 | 1993-10-15 | Stirring method of molten metal |
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| Country | Link |
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| JP (1) | JP2929912B2 (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5603749A (en) * | 1995-03-07 | 1997-02-18 | Bethlehem Steel Corporation | Apparatus and method for vacuum treating molten steel |
| JP2011214084A (en) * | 2010-03-31 | 2011-10-27 | Kobe Steel Ltd | Method for producing high cleanliness steel |
| CN112760506A (en) * | 2020-12-27 | 2021-05-07 | 上海交通大学安徽(淮北)陶铝新材料研究院 | System with electromagnetic stirring for controlling in-situ authigenic aluminum-based composite material through melt |
| CN112779434A (en) * | 2020-12-27 | 2021-05-11 | 上海交通大学安徽(淮北)陶铝新材料研究院 | Method for in-situ self-growing aluminum-based composite material with permanent magnet stirring |
| CN112813279A (en) * | 2020-12-27 | 2021-05-18 | 上海交通大学安徽(淮北)陶铝新材料研究院 | System for controlling in-situ authigenic aluminum-based composite material through melt with continuous treatment |
| CN112808991A (en) * | 2020-12-27 | 2021-05-18 | 上海交通大学安徽(淮北)陶铝新材料研究院 | In-situ autogenous aluminum matrix composite material system with permanent magnet stirring function |
| WO2022134610A1 (en) * | 2020-12-27 | 2022-06-30 | 上海交通大学安徽(淮北)陶铝新材料研究院 | Method for autonomously producing aluminum-based composite material in situ with melt control under electromagnetic stirring |
-
1993
- 1993-10-15 JP JP25820593A patent/JP2929912B2/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5603749A (en) * | 1995-03-07 | 1997-02-18 | Bethlehem Steel Corporation | Apparatus and method for vacuum treating molten steel |
| JP2011214084A (en) * | 2010-03-31 | 2011-10-27 | Kobe Steel Ltd | Method for producing high cleanliness steel |
| CN112760506A (en) * | 2020-12-27 | 2021-05-07 | 上海交通大学安徽(淮北)陶铝新材料研究院 | System with electromagnetic stirring for controlling in-situ authigenic aluminum-based composite material through melt |
| CN112779434A (en) * | 2020-12-27 | 2021-05-11 | 上海交通大学安徽(淮北)陶铝新材料研究院 | Method for in-situ self-growing aluminum-based composite material with permanent magnet stirring |
| CN112813279A (en) * | 2020-12-27 | 2021-05-18 | 上海交通大学安徽(淮北)陶铝新材料研究院 | System for controlling in-situ authigenic aluminum-based composite material through melt with continuous treatment |
| CN112808991A (en) * | 2020-12-27 | 2021-05-18 | 上海交通大学安徽(淮北)陶铝新材料研究院 | In-situ autogenous aluminum matrix composite material system with permanent magnet stirring function |
| WO2022134610A1 (en) * | 2020-12-27 | 2022-06-30 | 上海交通大学安徽(淮北)陶铝新材料研究院 | Method for autonomously producing aluminum-based composite material in situ with melt control under electromagnetic stirring |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2929912B2 (en) | 1999-08-03 |
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