JP2600656B2 - Drop degassing of molten steel - Google Patents
Drop degassing of molten steelInfo
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- JP2600656B2 JP2600656B2 JP61288541A JP28854186A JP2600656B2 JP 2600656 B2 JP2600656 B2 JP 2600656B2 JP 61288541 A JP61288541 A JP 61288541A JP 28854186 A JP28854186 A JP 28854186A JP 2600656 B2 JP2600656 B2 JP 2600656B2
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- Prior art keywords
- molten steel
- droplet
- degassing
- frequency
- fine
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- Treatment Of Steel In Its Molten State (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、溶鋼の流滴脱ガス法の改良に関するもので
ある。DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to an improvement in a method of dropping degassing molten steel.
（従来の技術及びその問題点） 溶鋼の脱ガス、特に脱水素に適した方法として流滴脱
ガス法が良く知られている。この流滴脱ガス法は、溶鋼
を減圧した受鋼容器内に入れるとその途端に溶鋼内のガ
スが圧力低下し、溶鋼が急激に逸出膨張して微細な小滴
となって飛散し、極めて大きなガス−メタル界面が瞬間
的に得られることによって脱ガスする方法である。(Conventional technology and its problems) As a method suitable for degassing molten steel, particularly for dehydrogenation, a droplet degassing method is well known. In this droplet degassing method, when molten steel is placed in a reduced-pressure steel receiving container, the pressure in the molten steel drops immediately, and the molten steel rapidly escapes and expands and scatters as fine droplets. This is a method of degassing by obtaining an extremely large gas-metal interface instantaneously.
すなわち、前記微細な小滴はその表面張力が大きい
為、小滴の表面と内部間での溶鋼の循環が極めて少な
く、よって小滴内部に位置する水素等は溶鋼内拡散によ
り小滴の表面まで移動して脱ガス発応が起こるのであ
る。勿論この小滴は微細になればなる程水素等の拡散す
る距離が短くなる為、第４図に破線で示すように脱ガス
効率は高くなる。That is, since the fine droplet has a large surface tension, the circulation of molten steel between the surface and the inside of the droplet is extremely small, so that hydrogen and the like located inside the droplet reach the surface of the droplet by diffusion in the molten steel. It moves and degassing occurs. Of course, as the size of the droplet becomes smaller, the diffusion distance of hydrogen and the like becomes shorter, so that the degassing efficiency becomes higher as shown by the broken line in FIG.
しかしながら、実操業において溶鋼流滴を形成させる
場合、平均粒径は1.5〜2.0mm程度と推定され、脱ガス効
率を高めるためにこの溶鋼流滴を更に微細化するには特
別な方法を付加する必要がある。However, when forming molten steel droplets in actual operation, the average particle size is estimated to be about 1.5 to 2.0 mm, and a special method is added to further refine the molten steel droplets in order to increase degassing efficiency There is a need.
なお、実操業において形成される1.5〜2.0mm程度の溶
鋼の微細流滴が減圧した受鋼容器内で落下する場合の脱
水素挙動は第４図に示すように推定され、実操業でも略
これに相応した水素値を得ている。In addition, the dehydrogenation behavior when the fine droplets of molten steel of about 1.5 to 2.0 mm formed in the actual operation fall in the depressurized steel receiving vessel is estimated as shown in FIG. The hydrogen value corresponding to.
一方、前記脱ガス（特に脱水素）反応の速度は溶鋼と
ガスが接触する界面積が大きくなると向上する。また、
同じ界面積であっても溶鋼の循環流によってその界面に
到達する機会が多い場合には単位溶鋼量当りと界面席は
見かけ上増大したことになる。これは溶鋼に与えられた
撹拌（循環）エネルギーによるものであり、溶鋼の表面
更新率に比例すると考えられている。On the other hand, the rate of the degassing (particularly, dehydrogenation) reaction increases as the interface area between the molten steel and the gas increases. Also,
Even if the boundary area is the same, if there are many chances of reaching the interface by the circulating flow of the molten steel, the per unit molten steel amount and the interface position have apparently increased. This is due to the stirring (circulation) energy given to the molten steel, and is considered to be proportional to the surface renewal rate of the molten steel.
すなわち、従来の流滴脱ガス法にあっては形成された
微細小滴は1.5〜2.0mm程度であり、この微細小滴の表面
張力の作用によって小滴内部と小滴表面の循環が強く抑
制されてしまっていたのである。That is, in the conventional droplet degassing method, the formed fine droplets are about 1.5 to 2.0 mm, and the circulation of the inside of the droplet and the surface of the droplet is strongly suppressed by the action of the surface tension of the fine droplet. It had been done.
本発明はかかる問題点に鑑みて成されたものであり、
溶鋼の微細小滴の表面更新率を向上せしめて脱ガス効率
を高めることができる流滴脱ガス法を提供せんとするも
のである。The present invention has been made in view of such problems,
It is an object of the present invention to provide a droplet degassing method capable of improving the degassing efficiency by improving the surface renewal rate of fine droplets of molten steel.
（問題点を解決するための手段） 本発明は、減圧した受鋼容器に溶鋼を注入して流滴化
させることにより溶鋼を脱ガスする流滴脱ガス法におい
て、前記受鋼容器より逸出膨張して飛散する微細小滴
に、その外表面から、コイルに最低許容周波数fc（＝12
8.5×106/K・μ・a2、但し、K:導電率，μ：比誘磁率,
a:微細小滴の半径）からこれの1/20の範囲の高周波電流
を流して前記微細小滴に渦電流を生じさせ、当該外表面
を誘導加熱により局部加熱することを要旨とするもので
ある。本発明の溶鋼の流滴脱ガス法において、微細小滴
に最低許容周波数fcからこれの1/20の範囲の高周波を供
給するのは、本発明者らの実験，研究によれば、これら
の範囲の高周波を供給すれば、有効な脱ガス効果が得ら
れるからである。(Means for Solving the Problems) The present invention is directed to a droplet degassing method in which molten steel is degassed by injecting molten steel into a depressurized steel receiving vessel and causing the molten steel to flow, thereby escaping from the steel receiving vessel. The smallest permissible frequency fc (= 12
8.5 × 10 6 / K · μ · a 2 , where K: conductivity, μ: relative magnetic permeability,
a: radius of a fine droplet) from which a high-frequency current in a range of 1/20 of this is passed to generate an eddy current in the fine droplet, and the outer surface is locally heated by induction heating. is there. In the droplet degassing method for molten steel according to the present invention, supplying high-frequency waves in the range of the minimum permissible frequency fc to 1/20 of the minimum permissible frequency fc according to the experiments and studies by the present inventors, If a high frequency in the range is supplied, an effective degassing effect can be obtained.
（作用） 本発明は、減圧した受鋼容器に溶鋼を注入して流滴化
させることにより溶鋼を脱ガスする流滴脱ガス法におい
て、前記受鋼容器より逸出膨張して飛散する微細小滴
に、その外表面から、コイルに最低許容周波数fc（＝12
8.5×106/K・μ・a2、但し、K:導電率，μ：比誘磁率,
a:微細小滴の半径）からこれの1/20の範囲の高周波電流
を流して前記微細小滴に渦電流を生じさせ、当該外表面
を誘導加熱により局部加熱するものであり、これによっ
て微細小滴内における溶鋼の循環を促進せしめ、微細小
滴表面の溶鋼の更新率が向上する。(Function) The present invention provides a droplet degassing method in which molten steel is degassed by injecting molten steel into a depressurized steel receiving vessel and causing the molten steel to form a droplet. The minimum permissible frequency fc (= 12)
8.5 × 10 6 / K · μ · a 2 , where K: conductivity, μ: relative magnetic permeability,
a: radius of a fine droplet) from which a high-frequency current in a range of 1/20 of this is passed to generate an eddy current in the fine droplet, and the outer surface is locally heated by induction heating. The circulation of the molten steel in the droplet is promoted, and the renewal rate of the molten steel on the surface of the fine droplet is improved.
（実 施 例） 以下本発明を第１図〜第３図に基づいて説明する。(Embodiment) Hereinafter, the present invention will be described with reference to FIGS. 1 to 3.
第１図において、１は取鍋、２は減圧された受鋼容器
であり、この受鋼容器２は上部槽３とその下方の脱ガス
処理室４とから構成され、その境界部に適宜の真空排気
装置に接続された真空排気ダクト５が配設されている。In FIG. 1, reference numeral 1 denotes a ladle and 2 denotes a depressurized steel receiving container. The steel receiving container 2 is composed of an upper tank 3 and a degassing treatment chamber 4 thereunder. An evacuation duct 5 connected to the evacuation device is provided.
６は前記脱ガス処理室４の排出口（本実施例では２
個）に設置された鋳込みノズルゲートであり、この鋳込
みノズルゲート６より排出される十分に脱ガス、特に脱
水素された溶鋼は、例えば連続鋳造鋳型７に注入される
ように成されている。Reference numeral 6 denotes an outlet of the degassing chamber 4 (2 in this embodiment).
The molten steel that has been sufficiently degassed, especially dehydrogenated, discharged from the casting nozzle gate 6 is injected into, for example, a continuous casting mold 7.
８は前記脱ガス処理室４の内周壁部に設置された例え
ば高周波コイルであり、上部槽３の排出口に設けられた
ノズルゲート９により脱ガス処理室４で流滴脱ガスされ
る溶鋼の微細小滴の表面を局部加熱するものである。Reference numeral 8 denotes, for example, a high-frequency coil installed on the inner peripheral wall of the degassing chamber 4. The nozzle 8 is provided at a discharge port of the upper tank 3. The surface of the fine droplet is locally heated.
本発明方法は例えば上記した構成の流滴脱ガス装置を
用いて行なうものであり、溶鋼は以下の如くして脱ガス
される。The method of the present invention is carried out by using, for example, a droplet degassing apparatus having the above-described configuration, and molten steel is degassed as follows.
すなわち、取鍋１に収容された溶鋼10は、取鍋１の底
面に設置されたノズル11から上部槽３に注入され、この
上部槽３の前記ノズルゲート９を介して真空に排気され
た脱ガス処理室４の内部に飛散し、ここで流滴脱ガス処
理が行われるのである。この時、本発明にあっては前記
飛散した微細小滴の外表面を高周波コイル８によって局
部加熱し、微細小滴内部における溶鋼の循環を促進せし
めるのである。That is, the molten steel 10 stored in the ladle 1 is injected into the upper tank 3 from the nozzle 11 installed on the bottom of the ladle 1, and is evacuated to vacuum through the nozzle gate 9 of the upper tank 3. The particles are scattered in the gas processing chamber 4, where the droplet degassing process is performed. At this time, in the present invention, the outer surface of the scattered fine droplets is locally heated by the high-frequency coil 8 to promote the circulation of molten steel inside the fine droplets.
かかる如くすることによって微細小滴外表面における
要項の更新率が向上し、脱ガス効率を高めることができ
るのである。By doing so, the renewal rate of the essential items on the outer surface of the fine droplets is improved, and the degassing efficiency can be increased.
ところで前記高周波による外部からのエネルギーは、
微細小滴の内部まで及ぶことが望ましいのであるが、高
周波の周波数と微細小滴と径の条件による制約から微細
小滴の外表面のみにとどまってもよい。いずれにしても
高周波によって付与されたエネルギーは微細小滴の外表
面を脱ガスに対して活性化させることに役立つ。By the way, external energy due to the high frequency is
Although it is desirable to extend to the inside of the fine droplet, it may be limited to only the outer surface of the fine droplet due to the restrictions of the high frequency and the conditions of the fine droplet and the diameter. In any case, the energy provided by the high frequency helps to activate the outer surface of the microdroplets against outgassing.
また。この高周波の付与は、本実施例のように微細小
滴の落下途中に行ってもよく、またノズルゲート９の直
下における微細小滴形成直後であってもよい。しかしな
がら、微細小滴が飛散して拡散した後に高周波を作用さ
せるとそのエネルギーの供給効率が低下するため、可能
な限りノズルゲート９に近い方が良い。Also. The application of the high frequency may be performed during the falling of the fine droplet as in the present embodiment, or may be performed immediately after the formation of the fine droplet directly below the nozzle gate 9. However, when high frequency is applied after the fine droplets are scattered and diffused, the energy supply efficiency is reduced. Therefore, it is better to be as close to the nozzle gate 9 as possible.
更に、高周波コイル８の巻数と高周波の及ぶ領域は多
い程及び広い程良いのであるが、微細小滴の飛散落下行
程に合った領域を選択することが肝要である。これらに
ついて以下に詳述する。Furthermore, the number of turns of the high-frequency coil 8 and the range to which the high-frequency wave is applied are preferably as large and wide as possible. However, it is important to select an area suitable for the scattering and falling process of the fine droplet. These are described in detail below.
（１） 周波数について 高周波の周波数は微細小滴を誘導加熱する場合の基本
的条件であり、微細小滴内への渦電流の浸透深さに密接
に関連する。また、誘導加熱ができる最低許容周波数fc
は第２図に示すように微細小滴の径によって決まり、こ
の時の渦電流の浸透深さＳは最低許容周波数によって決
まる。これらを下記、式に示す。(1) Frequency The frequency of high frequency is a basic condition for induction heating of a fine droplet, and is closely related to the penetration depth of an eddy current into the fine droplet. In addition, the minimum allowable frequency fc for induction heating
Is determined by the diameter of the fine droplet as shown in FIG. 2, and the penetration depth S of the eddy current at this time is determined by the lowest allowable frequency. These are shown in the formula below.
但し、fc:最低許容周波数（Hz） K:導電率（/cm） μ：比誘磁率 a:微細小滴の半径（cm） 実際に使用する周波数は上記式に示す最低許容周波
数が望ましいのであるが、これの1/10〜1/20の周波数で
あっても後述するように脱水素促進効果がある。これ
は、微細小滴の径の分布において最低許容周波数の1/10
〜1/20の周波数が前記分布内における径の大きい小滴に
エネルギーを与えて有効な脱ガス（脱水素）効果を発揮
したものと思慮される。 However, fc: lowest allowable frequency (Hz) K: conductivity (/ cm) μ: relative magnetic attraction a: radius of fine droplet (cm) The lowest allowable frequency shown in the above formula is desirable for the frequency actually used. However, even at a frequency of 1/10 to 1/20 of this, there is an effect of promoting dehydrogenation as described later. This is 1/10 of the lowest permissible frequency in the distribution of fine droplet diameter.
It is considered that a frequency of 1 / 1/20 imparted energy to the large diameter droplets in the distribution to exert an effective degassing (dehydrogenation) effect.
従って、実用上脱ガス効果を促進させるための周波数
は流滴脱ガスによって形成される微細小滴の平均粒滴径
から上記式によって求められる最低許容周波数fcの1/
10〜1/20程度のものでも十分である。すなわち、現状の
流滴脱ガスによって形成される微細小滴の径は1.5〜2.0
mmであるためにその半径ａは0.75〜1.0mmとなり、この
時の最低許容周波数fc＝1.8〜3.2×106Hzの1/10〜1/20
が実用上の周波数といえる。つまり１〜３×105Hzであ
る。Therefore, in practice, the frequency for promoting the degassing effect is 1/1 / the minimum allowable frequency fc obtained by the above equation from the average droplet diameter of the fine droplets formed by the droplet degassing.
About 10 to 1/20 is sufficient. That is, the diameter of the fine droplets formed by current droplet degassing is 1.5 to 2.0.
mm, the radius a is 0.75 to 1.0 mm, and the minimum allowable frequency fc at this time is 1/10 to 1/20 of 1.8 to 3.2 × 10 6 Hz.
Is a practical frequency. That is, it is 1-3 × 10 5 Hz.
（２） 高周波出力について 通常、１〜500KHzの高周波の最大出力は500KW程度で
ある。(2) High frequency output Normally, the maximum output of high frequency of 1 to 500 KHz is about 500 KW.
しかして、流滴脱ガス処理時に高周波を使用する場合
には溶鋼の通過量すなわち処理量と上昇させるべき温度
によって高周波出力を決定する。In the case where a high frequency is used during the droplet degassing process, the high frequency output is determined according to the amount of molten steel passing through, that is, the throughput and the temperature to be raised.
実操業での処理量は約４〜5TON/分であるため、前記
した最大出力500KWを使用すればこの溶鋼を約10℃上昇
させることができる。なお、効率を考慮しても６〜８℃
上昇させることができる。Since the throughput in the actual operation is about 4 to 5 TON / min, the molten steel can be raised by about 10 ° C. if the above-mentioned maximum output of 500 KW is used. In addition, 6 to 8 ° C.
Can be raised.
（３） コイル巻数について コイル巻数は流滴と高周波享受領域と関連し、第３図
に示すように実際に高周波の影響を受けるこの領域が長
い程脱ガス効率が良好である。なお、第３図は微細小滴
の径が約1.5mm、落下距離が1600mm、初期の水素濃度が4
ppmの場合における脱水素状況の比較をした結果を示す
もので、第３図中における高周波処理Ａはコイル巻数が
５の場合、高周波処理Ｂはコイル巻数が９の場合を示し
ている。(3) Regarding the number of coil turns The number of coil turns is related to the droplet and the high-frequency receiving area. As shown in FIG. 3, the longer the area actually affected by the high frequency, the better the degassing efficiency. FIG. 3 shows that the diameter of the fine droplet is about 1.5 mm, the falling distance is 1600 mm, and the initial hydrogen concentration is 4 mm.
FIG. 3 shows the results of comparison of the dehydrogenation situation in the case of ppm. In FIG. 3, high frequency processing A shows a case where the number of coil turns is 5, and high frequency processing B shows a case where the number of coil turns is 9.
次に本発明方法を実施した結果について述べる。 Next, the results of implementing the method of the present invention will be described.
実施結果 （１） 第１図に示す構成の流滴脱ガス装置を用いて溶鋼から
脱水素の挙動を調査した。使用した溶鋼は下記第１表に
示す成分を有するもので、また、高周波はその周波数が
1.5×105Hzのものを使用し、この時と出力は480〜500KW
に設定した。Results (1) The behavior of dehydrogenation from molten steel was investigated using a droplet degassing apparatus having the configuration shown in FIG. The molten steel used had the components shown in Table 1 below.
Use 1.5 × 10 5 Hz, and at this time the output is 480 ~ 500KW
Set to.
前記した成分の溶鋼5TONを径φ20mmのノズルゲートか
ら0.8Torrに維持した脱ガス処理室内に導入した。この
場合の平均処理速度は5kg/秒、落下距離すなわちノズル
ゲートの下端から脱ガス処理室内の溶鋼表面までの距離
は平均1600mmであった。 5TON of molten steel of the above-described component was introduced into a degassing chamber maintained at 0.8 Torr from a nozzle gate having a diameter of 20 mm. In this case, the average processing speed was 5 kg / sec, and the falling distance, that is, the distance from the lower end of the nozzle gate to the surface of the molten steel in the degassing chamber was 1600 mm on average.
その結果を下記第２表に示す。 The results are shown in Table 2 below.
上記第２表より明らかなように、本発明法Ａの場合に
は処理後の成分は水素濃度〔Ｈ〕が0.7ppmとなり、同条
件で高周波を作用させない従来法の1.2ppmと比較して脱
水素率は70％から83％に向上した。また、本発明法Ｂの
場合には水素濃度〔Ｈ〕は0.5ppmとなり、更に脱水素が
促進された。この場合の脱水素率は88％であった。 As is clear from Table 2 above, in the case of the method A of the present invention, the hydrogen concentration [H] of the component after the treatment was 0.7 ppm, which was lower than that of 1.2 ppm in the conventional method in which no high frequency was applied under the same conditions. The rate increased from 70% to 83%. In the case of the method B of the present invention, the hydrogen concentration [H] was 0.5 ppm, and dehydrogenation was further promoted. The dehydrogenation rate in this case was 88%.
一方、窒素については従来法では30〜32ppmとあまり
脱窒素が成されていないが、本発明法の場合には両者共
25〜27ppmに低下し、脱窒素にも効果を有することが判
明した。On the other hand, nitrogen is not denitrated as much as 30 to 32 ppm in the conventional method, but both are degraded in the method of the present invention.
It was lowered to 25 to 27 ppm, which proved to be effective for denitrification.
実施結果 （２） 高周波の周波数を３種類変更し、その他の条件は上記
実施結果（１）と同様にして脱水素の挙動を調査した。Implementation result (2) The dehydrogenation behavior was investigated in the same manner as in the implementation result (1) above, except that the frequency of the high frequency was changed to three types.
その結果を下記第３表に示す。 The results are shown in Table 3 below.
上記第３表により明らかなように、周波数が２×1
06、1.5×105の場合には高周波を付与した効果が得られ
ているが、５×104の場合には高周波を付与した効果が
得られていない。 As is clear from Table 3 above, the frequency is 2 × 1
In the case of 0 6 and 1.5 × 10 5 , the effect of imparting high frequency was obtained, but in the case of 5 × 10 4 , the effect of imparting high frequency was not obtained.
すなわち、処理前の水素濃度が4ppm程度のものを落下
距離1600mmの間に0.6ppm以下にするためには前記式で
得られる最低周波数の1/10〜1/20程度の高周波を作用さ
せなければならないことは明らかである。In other words, in order to make the hydrogen concentration before treatment about 4 ppm to 0.6 ppm or less during the drop distance of 1600 mm, a high frequency of about 1/10 to 1/20 of the lowest frequency obtained by the above equation must be applied. Obviously this is not the case.
実施結果 （３） 第１図に示すような高周波コイルを設けた流滴脱ガス
装置を用い、かつ受鋼容器下方からの鋳込みを行わずに
ノズルゲートから溶鋼表面迄の微細小滴の落下距離を平
均800mmとして脱水素の挙動を調査した。なお、この場
合の高周波の周波数は1.5×105Hz、出力は約500KWに設
定し、また真空度は0.7〜0.8Torrで溶鋼の処理前水素濃
度は4.2ppm、同じく窒素濃度は24ppmであった。(3) The falling distance of fine droplets from the nozzle gate to the surface of the molten steel without using casting from below the steel receiving container using a drop degassing device equipped with a high-frequency coil as shown in Fig. 1 Was 800 mm on average, and the behavior of dehydrogenation was investigated. In this case, the frequency of the high frequency was set to 1.5 × 10 5 Hz, the output was set to about 500 KW, the degree of vacuum was 0.7 to 0.8 Torr, the hydrogen concentration before treatment of the molten steel was 4.2 ppm, and the nitrogen concentration was also 24 ppm. .
かかる条件で流滴脱ガスを行った結果、処理後の水素
濃度は0.8ppmで脱水素率は81％、同じく窒素濃度は24pp
m迄低下した。As a result of drop degassing under these conditions, the hydrogen concentration after treatment was 0.8 ppm, the dehydrogenation rate was 81%, and the nitrogen concentration was 24 pp.
m.
すなわち、本結果より本発明方法を適用することによ
って微細小滴の落下距離を従来より短くしても脱ガス効
率が良くなることが明らかであり、流滴脱ガス装置の小
型化が指向できる。That is, it is clear from the results that the degassing efficiency can be improved by applying the method of the present invention even if the falling distance of the fine droplets is made shorter than before, and the size of the droplet degassing apparatus can be reduced.
（発明の効果） 以上説明したように本発明は、減圧した受鋼容器に溶
鋼を注入して流滴化させることにより溶鋼を脱ガスする
流滴脱ガス法において、前記受鋼容器より逸出膨張して
飛散する微細小滴に、その外表面から、コイルに最低許
容周波数fc（＝128.5×106/K・μ・a2、但し、K:導電
率，μ：比誘磁率,a:微細小滴の半径）からこれの1/20
の範囲の高周波電流を流して前記微細小滴に渦電流を生
じさせ、当該外表面を誘導加熱により局部加熱するが促
進されてその表面の更新が活発になる。そして、これに
より見かけ上のガス−メタル界面積が増大して脱ガス効
率が良くなる。また、本発明によれば微細小滴の落下距
離を短くすることができる為、装置を小型化できその費
用の低減も可能となる。更に、本発明によれば従来ほと
んど期待できなかった脱窒素も起こる。(Effects of the Invention) As described above, the present invention provides a method for degassing molten steel by injecting molten steel into a depressurized steel receiving vessel and causing the molten steel to flow, thereby escaping from the steel receiving vessel. The minimum allowable frequency fc (= 128.5 × 10 6 / K · μ · a 2 , where K: conductivity, μ: relative magnetic permeability, a: 1/20 of this from the radius of the fine droplet)
A high-frequency current in the range (1) is caused to generate an eddy current in the fine droplet, and the external surface is locally heated by induction heating, and the renewal of the surface becomes active. As a result, the apparent gas-metal interface area increases, and the degassing efficiency improves. Further, according to the present invention, since the falling distance of the fine droplet can be shortened, the apparatus can be downsized and the cost can be reduced. Furthermore, according to the present invention, denitrification, which has hardly been expected in the past, also occurs.
第１図は本発明法を実施するための流滴脱ガス装置の一
例を示す概略説明図、第２図は溶鋼の微細小滴半径と最
低許容周波数の関係を示す図面、第３図は本発明法と従
来法における脱水素状況の比較図、第４図は流滴脱ガス
法における脱水素の挙動を示す図面である。 ２は受鋼容器、３は上部槽、４は脱ガス処理室、８は高
周波コイル。1 is a schematic explanatory view showing an example of a droplet degassing apparatus for carrying out the method of the present invention, FIG. 2 is a drawing showing the relationship between the radius of fine droplets of molten steel and the minimum allowable frequency, and FIG. FIG. 4 is a diagram showing a comparison of the dehydrogenation status between the invention method and the conventional method, and FIG. 2 is a steel container, 3 is an upper tank, 4 is a degassing chamber, and 8 is a high-frequency coil.
Claims (1)
させることにより溶鋼を脱ガスする流滴脱ガス法におい
て、前記受鋼容器より逸出膨張して飛散する微細小滴
に、その外表面から、コイルに下記式で算出される最低
許容周波数fcからこれの1/20の範囲の高周波電流を流し
て前記微細小滴に渦電流を生じさせ、当該外表面を誘導
加熱により局部加熱することを特徴とする溶鋼の流滴脱
ガス法。 但し、fc:最低許容周波数（Hz） K:導電率（/cm） μ：比誘磁率 a:微細小滴の半径（cm）In a droplet degassing method in which molten steel is degassed by pouring molten steel into a depressurized steel receiving vessel to form droplets, fine droplets escaping from the steel receiving vessel to expand and scatter are removed. From the outer surface, a high-frequency current in the range of 1/20 of the minimum allowable frequency fc calculated by the following equation is applied to the coil to generate an eddy current in the fine droplet, and the outer surface is subjected to induction heating. A droplet degassing method for molten steel characterized by local heating. Where fc: Minimum allowable frequency (Hz) K: Conductivity (/ cm) μ: Specific magnetic permeability a: Radius of fine droplet (cm)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61288541A JP2600656B2 (en) | 1986-12-03 | 1986-12-03 | Drop degassing of molten steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61288541A JP2600656B2 (en) | 1986-12-03 | 1986-12-03 | Drop degassing of molten steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63143217A JPS63143217A (en) | 1988-06-15 |
| JP2600656B2 true JP2600656B2 (en) | 1997-04-16 |
Family
ID=17731572
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61288541A Expired - Lifetime JP2600656B2 (en) | 1986-12-03 | 1986-12-03 | Drop degassing of molten steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2600656B2 (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50161404A (en) * | 1974-06-21 | 1975-12-27 |
-
1986
- 1986-12-03 JP JP61288541A patent/JP2600656B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63143217A (en) | 1988-06-15 |
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