JP2896838B2 - Molten steel manufacturing method - Google Patents
Molten steel manufacturing methodInfo
- Publication number
- JP2896838B2 JP2896838B2 JP32908693A JP32908693A JP2896838B2 JP 2896838 B2 JP2896838 B2 JP 2896838B2 JP 32908693 A JP32908693 A JP 32908693A JP 32908693 A JP32908693 A JP 32908693A JP 2896838 B2 JP2896838 B2 JP 2896838B2
- Authority
- JP
- Japan
- Prior art keywords
- slag
- hot metal
- refining
- molten steel
- equation
- Prior art date
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- Expired - Lifetime
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Description
【０００１】[0001]
【産業上の利用分野】本発明は溶鋼製造法にかかわり、
特に脱炭滓の熱間再利用法に関する。The present invention relates to a method for producing molten steel,
In particular, it relates to a method for hot-reusing decarburized slag.
【０００２】[0002]
【従来の技術】純酸素を鋼浴中央直上よりスラグを通し
て吹き付け吹錬する転炉法は、純酸素を用いるため鋼中
の窒素が低くなり、かつ高温が得られやすく、石灰の滓
化が速やかなため脱りんが脱炭と並行して進行する特色
をもつが、このとき生成する転炉滓は溶銑予備処理スラ
グとして再利用が可能であることが知られている。2. Description of the Related Art The converter method in which pure oxygen is blown and blown from above the center of a steel bath through slag reduces the nitrogen in steel because pure oxygen is used, and high temperatures can be easily obtained. Therefore, it is known that dephosphorization has the characteristic of proceeding in parallel with decarburization, but the converter slag generated at this time can be reused as hot metal pretreatment slag.
【０００３】例えば特公昭５５−３００４２号公報で
は、適当な処理容器内に収容した溶銑にそのｔ当り６〜
１５０ｋｇの転炉滓と１０〜４０ｋｇ酸素相当分の酸化
鉄とを主成分とする脱りん剤を添加し、これによって生
成した溶融スラグと溶銑とを適宜の手段で十分に攪拌混
合し、溶銑中のりん含有量を低下させることが開示され
ている。[0003] For example, Japanese Patent Publication No. 55-30042 discloses that hot metal contained in an appropriate treatment vessel is charged with 6 to
A dephosphorizing agent containing 150 kg of converter slag and iron oxide equivalent to 10 to 40 kg of oxygen as main components is added, and the resulting molten slag and hot metal are sufficiently stirred and mixed by appropriate means. To reduce the phosphorus content of
【０００４】しかしながら転炉滓を再装入するには転炉
滓破砕設備を有する必要がある点、また排滓時に熱ロス
が生じる点が解決されていなかった。この問題点を解決
するために、特開平２−１８１９８９号公報において、
高炉溶銑を精錬して溶鋼を製造する際に、第一工程とし
て溶銑を転炉に装入し、第二工程としてフラックス添加
と酸素吹込みを行って脱りん精錬を施し、所定のりん含
有量まで低減させ、第三工程として前記転炉を傾動して
第二工程で生成したスラグを排出し、その後第四工程と
して同一転炉にてフラックス添加と酸素吹錬により、所
定のＣ含有量まで脱炭を行い、第五工程として第四工程
で生成したスラグを該転炉内に残したまま出鋼して、再
び第一工程へ戻り、前記第五工程までを繰り返し実施す
る溶鋼製造法が提案されている。[0004] However, re-loading the converter slag requires the provision of a converter smash crushing facility and the problem of heat loss at the time of discharging the slag has not been solved. In order to solve this problem, Japanese Patent Application Laid-Open No.
When refining blast furnace molten iron to produce molten steel, the molten iron is charged to a converter as the first step, and the second step is performed by adding flux and oxygen to perform dephosphorization refining, and the specified phosphorus content As a third step, the converter is tilted and the slag generated in the second step is discharged, and then, as a fourth step, flux addition and oxygen blowing in the same converter to a predetermined C content. Decarbonization is performed, and as a fifth step, the molten steel is produced by tapping while leaving the slag generated in the fourth step in the converter, returning to the first step, and repeatedly performing the steps up to the fifth step. Proposed.
【０００５】[0005]
【発明が解決しようとする課題】転炉脱炭滓は一般に酸
素活量が高く、転炉脱炭滓を溶融状態で転炉に残したま
ま溶銑を装入した場合、溶銑中の炭素と転炉脱炭滓中の
酸素が爆発的に反応し、時として突沸あるいはスラグフ
ォーミングにより操業に支障をきたすという問題点があ
る。The converter decarburized slag generally has a high oxygen activity, and when molten iron is charged while leaving the converter decarburized slag in the converter in a molten state, carbon and carbon in the molten iron are not converted. There is a problem that the oxygen in the furnace decarburization reacts explosively and sometimes the operation is hindered by bumping or slag forming.
【０００６】本発明は、溶融脱炭滓を転炉内に残したま
ま溶銑装入する際に発生する突沸やスラグフォーミング
を抑制する製鋼法を提供することを目的とするものであ
る。An object of the present invention is to provide a steelmaking method which suppresses bumping and slag forming that occur when hot metal is charged while leaving molten decarburized slag in a converter.
【０００７】[0007]
【課題を解決するための手段】本発明は上述の課題を有
利に解決したものであり、その要旨とするところは、精
錬容器にて脱炭処理を行う際に生成する脱炭滓を前記精
錬容器に残したまま出鋼し、下記の式を満足する条件
で次の溶銑を装入し、脱りん処理あるいは脱炭精錬する
ことを特徴とする溶鋼製造法にあり、また式の条件を
満足させるために冷却剤あるいは冷却剤と脱酸剤の混合
物を脱炭滓に添加することを特徴とする溶鋼製造法にあ
る。SUMMARY OF THE INVENTION The present invention advantageously solves the above-mentioned problems, and the gist of the present invention is to remove the decarburized slag generated when performing decarburization in a refining vessel. It is a method for producing molten steel characterized by discharging the steel while leaving it in the vessel, charging the next molten iron under the conditions that satisfy the following formula, and performing dephosphorization treatment or decarburization refining. A method for producing molten steel, characterized by adding a cooling agent or a mixture of a cooling agent and a deoxidizing agent to the decarburized slag in order to achieve this.
【０００８】[0008]
【数４】 (Equation 4)
【０００９】[0009]
【作用】以下本発明について詳細に説明する。本発明は
例えば、溶銑予備処理工程と脱炭工程とを集約し同一転
炉によって溶鋼を製造する際に用いられる。図２に示す
ように、炉底にガスを吹込むための１個ないし複数個の
底吹き羽口と、出鋼孔と対面炉腹にスラグフォーミング
用ガス吹込みのための複数個の羽口を備えた上底吹き転
炉に、前のチャージにおける脱炭滓をそのまま放置して
おく。このように、脱炭滓を転炉に残した状態で溶銑を
装入した場合、時として脱炭滓の酸素源、即ちＦｅＯ，
Ｆｅ2 Ｏ3 ，ＭｎＯと溶銑中の炭素が急激に下記の式
から式の反応を起こし、多量のＣＯガスを発生し、こ
のＣＯガスにより炉内からスラグおよび装入した溶銑が
激しく飛出し、あるいはスラグフォーミングが生じて炉
内からスラグが流出し、鉄歩留りを低下させるばかりで
はなく操業中断を余儀なくされることがある。しかも場
合によっては設備破損をも引き起こすこともある。The present invention will be described below in detail. The present invention is used, for example, when the molten iron pretreatment step and the decarburization step are integrated to produce molten steel by the same converter. As shown in FIG. 2, one or a plurality of tuyere tuyeres for injecting gas into the furnace bottom and a plurality of tuyeres for injecting gas for slag forming are provided at the tapping hole and the opposite side of the furnace. The decarburized slag from the previous charge is left in the top-bottom blow converter. As described above, when the hot metal is charged while the decarburized slag remains in the converter, the oxygen source of the decarburized slag, namely, FeO,
Fe 2 O 3 , MnO and the carbon in the hot metal rapidly react with the following equation to generate a large amount of CO gas, and this CO gas causes slag and the charged hot metal to fly out of the furnace violently, Alternatively, slag forming may occur, causing slag to flow out of the furnace, not only lowering the iron yield, but also causing the operation to be interrupted. In some cases, the equipment may be damaged.
【００１０】[0010]
【数５】 (Equation 5)
【００１１】先に示したから式の反応によって生じ
るＣＯガス量はスラグ中のＦｅＯあるいはＦｅ2 Ｏ3 あ
るいはＭｎＯ濃度が高い程多くなる。またこれらの反応
の速度はスラグあるいは溶銑の温度が高い程速くなる。
つまり温度が高い程、急激な反応を引き起こす。しかし
スラグ中のＦｅＯあるいはＦｅ2 Ｏ3 あるいはＭｎＯ濃
度が高くても、スラグあるいは溶銑の温度が低い場合に
は反応の速度が遅く、突沸やスラグフォーミングが生じ
ないこともある。As indicated above, the amount of CO gas generated by the reaction of the formula increases as the concentration of FeO, Fe 2 O 3 or MnO in the slag increases. The rate of these reactions increases as the temperature of the slag or hot metal increases.
That is, the higher the temperature, the more rapid the reaction. However, even if the concentration of FeO, Fe 2 O 3, or MnO in the slag is high, the reaction speed is slow when the temperature of the slag or hot metal is low, and bumping or slag forming may not occur.
【００１２】そこで本発明者らは、突沸やスラグフォー
ミング発生におよぼすスラグ中のＦｅＯ，Ｆｅ2 Ｏ3 ，
ＭｎＯ濃度およびスラグ温度および溶銑温度の影響を詳
細に調査した結果、突沸やスラグフォーミングを防止す
るためには先に示した式を満たすことが必要であるこ
とを見出した。この式は左辺におけるＴ．Ｆｅ（Ｆｅ
ＯとＦｅ2 Ｏ3 中の鉄分濃度の和）、ＭｎＯ濃度とスラ
グおよび溶銑の関係が０．１以下である場合には突沸や
スラグフォーミングが起こらないことを意味している。
即ち、スラグ中のＦｅＯ，Ｆｅ2 Ｏ3 ，ＭｎＯ濃度に見
合って、式の左辺が０．１以下になるようなスラグあ
るいは溶銑温度とした後、溶銑を装入することで突沸や
スラグフォーミングを防ぐことが可能となる。また、こ
れとは逆にスラグおよび溶銑温度をもとに、式の関係
を満たすようにスラグのＴ．Ｆｅ，ＭｎＯ濃度を調整し
溶銑を装入することでも突沸やスラグフォーミングを防
ぐことが可能である。Therefore, the inventors of the present invention have found that FeO, Fe 2 O 3 ,
As a result of investigating the effects of the MnO concentration, the slag temperature and the hot metal temperature in detail, it was found that it was necessary to satisfy the above-described formula in order to prevent bumping and slag forming. This equation is equivalent to T.V. Fe (Fe
The sum of the iron concentrations in O and Fe 2 O 3), the relationship of MnO concentration and slag and hot metal it is meant that not occur bumping and slag foaming when it is 0.1 or less.
That is, after setting the slag or hot metal temperature such that the left side of the equation becomes 0.1 or less in accordance with the FeO, Fe 2 O 3 , and MnO concentrations in the slag, bumping and slag forming are performed by charging the hot metal. Can be prevented. Conversely, based on the slag and hot metal temperatures, the slag T.V. It is also possible to prevent bumping and slag forming by adjusting the Fe and MnO concentrations and charging the hot metal.
【００１３】なお、式を満足するように、脱炭滓中の
酸化鉄とマンガン酸化物濃度の和および次のチャージの
溶銑温度から決まる脱炭滓の温度になるまで溶銑装入を
待ってもよいが、ＣａＣＯ3 などのような冷却剤あるい
はコークス、無煙炭などのような脱酸剤との混合物を添
加し、強制的に式を満足する条件をつくりだしても良
い。In order to satisfy the formula, it is necessary to wait for charging of hot metal until the temperature of the decarburized slag is determined by the sum of the iron oxide and manganese oxide concentrations in the decarburized slag and the hot metal temperature of the next charge. It is preferable to add a coolant such as CaCO 3 or a mixture with a deoxidizing agent such as coke or anthracite to forcibly create conditions satisfying the formula.
【００１４】例えば冷却剤としてＣａＣＯ3 を使用した
場合、ＣａＣＯ3 がＣａＯとＣＯ2に分解するが、この
分解反応は吸熱反応であるため脱炭滓の温度が下がり、
短時間で先に示した式の条件を満足することができ
る。また、分解後のＣａＯは脱りん反応のフラックスと
して働くため、脱りん期の脱りん用フラックスを削減す
ることができ有用である。For example, when CaCO 3 is used as a cooling agent, CaCO 3 is decomposed into CaO and CO 2. Since this decomposition reaction is an endothermic reaction, the temperature of the decarburized slag decreases.
The condition of the above-described equation can be satisfied in a short time. In addition, since CaO after decomposition serves as a flux for the dephosphorization reaction, the flux for dephosphorization at the dephosphorization stage can be reduced, which is useful.
【００１５】脱炭滓中の酸化鉄とマンガン酸化物濃度の
和は、スラグサンプルを採取し迅速に分析するか、ある
いは溶鋼中炭素濃度と脱炭滓中の酸化鉄とマンガン酸化
物濃度の和の関係を求めておき、前チャージの脱炭後の
溶鋼中炭素濃度の分析結果から算出する。また段炭滓の
温度は放射温度計などによって測定する。先に示した
式の条件を満たした後、溶銑を装入し、前述の底吹羽口
よりガスを吹込み攪拌を行い、上吹きランスから酸素ガ
スを吹き付け、上方よりフラックスを、投入、吹込み、
突き付け等の方法で添加して、生成スラグ中の酸化鉄濃
度を制御することにより、脱りんを促進させる。溶銑装
入前にＣａＣＯ3 を添加した場合は、この時のフラック
ス量を削減できる。[0015] The sum of the iron oxide and manganese oxide concentrations in the decarburized slag can be determined by taking a slag sample and analyzing it promptly or by the sum of the carbon concentration in the molten steel and the iron oxide and manganese oxide concentrations in the decarburized slag. Is calculated from the analysis result of the carbon concentration in the molten steel after the decharging of the pre-charge. The temperature of the coal ash is measured by a radiation thermometer or the like. After satisfying the conditions of the formula shown above, hot metal is charged, gas is blown in from the above-mentioned bottom blowing tuyere, stirring is performed, oxygen gas is blown from the top blowing lance, and flux is injected and blown from above. Including
Dephosphorization is promoted by controlling the iron oxide concentration in the produced slag by adding it by a method such as butt. If CaCO 3 is added before charging the hot metal, the amount of flux at this time can be reduced.
【００１６】所定のりん含有量まで低下した時点で炉を
反出鋼側（排滓側）に傾動しスラグのみを排出させる。
排滓終了と共に直ちに炉を正立させ、副原料（耐火物保
護、復りん防止用生石灰、ドロマイト、鉄鉱石、Ｍｎ鉱
石等）を投入して通常の上底吹き脱炭精錬を行う。吹止
後、溶鋼は出鋼するが、脱炭滓はそのまま炉内に残し、
次のチャージの脱りん処理用フラックスとして活用す
る。At the time when the content of phosphorus has been reduced to a predetermined value, the furnace is tilted to the counter-steel side (discharge side) to discharge only slag.
Immediately after the waste is finished, the furnace is erected immediately, and auxiliary raw materials (quicklime, dolomite, iron ore, Mn ore, etc.) for refractory protection and phosphorus recovery prevention are charged, and ordinary top-bottom blowing decarburization refining is performed. After blowing, the molten steel is tapped, but the decarburized slag remains in the furnace,
Use it as a dephosphorization flux for the next charge.
【００１７】[0017]
【実施例】３２０Ｔ転炉を用いて、脱炭工程に生じた脱
炭滓を排滓することなく、転炉炉内に残置し、先に示し
た式の条件を満たした後に次のチャージの溶銑を装入
し、脱りん処理用フラックスとして再利用する操業を行
った。また比較のため、式の条件を満たさない場合で
も溶銑を装入した。この時の溶銑温度は１３５０℃であ
った。その結果を図１に示す。EXAMPLE Using a 320T converter, the decarburized slag generated in the decarburization process is left in the converter furnace without being discharged, and after satisfying the condition of the above equation, the next charge is removed. The operation of charging hot metal and reusing it as flux for dephosphorization was performed. For comparison, hot metal was charged even when the conditions of the formula were not satisfied. The hot metal temperature at this time was 1350 ° C. The result is shown in FIG.
【００１８】図１の斜線部は先に示した式の条件を満
たす範囲である。また○印は溶銑を装入した際に突沸や
スラグフォーミングが発生しなかった場合、×印は溶銑
を装入した際に突沸やスラグフォーミングが発生した場
合を示す。式の条件を満たさず溶銑を装入した場合
は、必ず突沸やスラグフォーミングが発生したが、式
の条件を満たした場合には、全く突沸やスラグフォーミ
ングが発生せず操業に支障を来さなかった。The shaded area in FIG. 1 is a range that satisfies the condition of the above-described equation. The mark ○ indicates that bumping or slag forming did not occur when the hot metal was charged, and the mark X indicates the case where bumping or slag forming occurred when the hot metal was charged. When hot metal was charged without satisfying the conditions of the formula, bumping and slag forming always occurred, but when the conditions of the formula were satisfied, no bumping and slag forming occurred and no hindrance to operation. Was.
【００１９】また、冷却剤としてＣａＣＯ3 を溶銑装入
前に５ｋｇ／ｔ添加した場合、添加しない場合に比べ、
先に示した式を満たすまでの時間が７分間短縮でき
た。さらに、ＣａＣＯ3 とコークスの混合物を添加した
場合には、１０分間の短縮ができた。以上本発明を主と
して同一転炉で溶銑予備処理と脱炭処理を行う例につい
て説明したが、本発明はこれに限定されるものではな
く、通常の酸素吹錬による脱炭処理後出鋼し、脱炭滓を
転炉に残置して、先に示した式の条件を満たした後、
溶銑を注湯して、脱炭滓の熱間再利用を図る方法もむろ
ん本発明の範囲を逸脱するものではない。Also, when CaCO 3 was added as a cooling agent at a rate of 5 kg / t before charging hot metal, compared with the case where CaCO 3 was not added,
The time required to satisfy the above equation was reduced by 7 minutes. Further, when a mixture of CaCO 3 and coke was added, the time was shortened by 10 minutes. Although an example in which the present invention mainly performs hot metal pretreatment and decarburization processing in the same converter has been described, the present invention is not limited to this, and tapping after decarburization processing by ordinary oxygen blowing, After leaving the decarburized slag in the converter and satisfying the conditions of the formula shown above,
A method of pouring molten iron to hot-recycle decarburized slag does not depart from the scope of the present invention.
【００２０】[0020]
【発明の効果】本発明によると、少なくとも同一転炉を
用いて溶銑予備処理および脱炭処理を繰り返し行う製鋼
法において、脱炭滓を炉内に残し、これを溶銑予備処理
用のフラックスとして用いる際に、溶銑装入時に生じる
突沸やスラグフォーミングの発生を抑制することがで
き、安定した操業が可能となる。According to the present invention, in a steelmaking method in which at least the same converter is used to repeatedly perform hot metal pretreatment and decarburization, the decarburized slag is left in the furnace and is used as a flux for hot metal pretreatment. In this case, bumping and slag forming that occur during hot metal charging can be suppressed, and stable operation can be achieved.
【図１】脱炭滓中の酸化鉄とマンガン酸化物の濃度の和
と突沸臨界脱炭滓温度の関係を示す図である。FIG. 1 is a graph showing the relationship between the sum of the concentrations of iron oxide and manganese oxide in decarburized slag and the temperature of bumping critical decarburized slag.
【図２】同一転炉による精錬プロセスの模式的説明図で
ある。FIG. 2 is a schematic explanatory view of a refining process using the same converter.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 升光 法行 北海道室蘭市仲町12番地 新日本製鐵株 式会社 室蘭製鐵所内 (72)発明者 小泉 文夫 北海道室蘭市仲町12番地 新日本製鐵株 式会社 室蘭製鐵所内 (56)参考文献 特開 平５−140627（ＪＰ，Ａ) 特開 平４−72007（ＪＰ，Ａ) 特開 平２−19416（ＪＰ，Ａ) 特開 平５−9533（ＪＰ，Ａ) (58)調査した分野(Int.Cl.6，ＤＢ名) C21C 5/28 C21C 1/02 110 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Noriyuki Shomitsu Nakamachi, Muroran City, Hokkaido Nippon Steel Corporation Muroran Works (72) Inventor Fumio Koizumi 12, Nakamachi, Muroran City, Hokkaido Nippon Steel Corporation (56) References JP-A-5-140627 (JP, A) JP-A-4-72007 (JP, A) JP-A-2-19416 (JP, A) JP-A-5-140 9533 (JP, A) (58) Field surveyed (Int. Cl. 6 , DB name) C21C 5/28 C21C 1/02 110
Claims (3)
る脱炭滓を前記精錬容器に残したまま出鋼し、下記の
式を満足する条件で次の溶銑を装入し、脱りん処理ある
いは脱炭精錬することを特徴とする溶鋼製造法。 【数１】 Claims: 1. De-stealing while leaving decarburized slag generated during decarburization treatment in a smelting vessel in the smelting vessel, charging the next hot metal under conditions satisfying the following equation, A method for producing molten steel, characterized by phosphorus treatment or decarburization refining. (Equation 1)
一工程として溶銑を精錬容器に装入し、第二工程として
フラックス添加と酸素吹込みを行って脱りん精錬を施し
所定のりん含有量まで低減させ、第三工程として前記精
錬容器を傾動して第二工程で生成したスラグを排出し、
その後第四工程として同一精錬容器にて脱炭を行い、第
五工程として第四工程で生成したスラグを該精錬容器内
に残したまま出鋼して、再び第一工程へ戻り、繰り返し
上記工程を行う溶鋼製造法の第一工程において、下記の
式を満足する条件で次の溶銑を装入することを特徴と
する溶鋼製造法。 【数２】 2. When refining molten iron to produce molten steel, the molten iron is charged into a refining vessel as a first step, and a dephosphorization refining is performed by performing flux addition and oxygen blowing as a second step. To reduce the phosphorus content, as a third step tilting the smelting vessel to discharge the slag generated in the second step,
Thereafter, as a fourth step, decarburization is performed in the same refining vessel, and as a fifth step, the slag generated in the fourth step is left in the refining vessel, and the steel is returned to the first step. In the first step of the method for producing molten steel, the following molten iron is charged under conditions satisfying the following equation. (Equation 2)
剤と脱酸剤の混合物を添加し、下記の式を満足する条
件で溶銑を装入することを特徴とする請求項１乃至２項
の何れかに記載の溶鋼製造法。 【数３】 3. The method according to claim 1, wherein a cooling agent or a mixture of a cooling agent and a deoxidizing agent is added before charging the hot metal, and the hot metal is charged under a condition satisfying the following equation. The method for producing molten steel according to any one of the above items. (Equation 3)
Priority Applications (10)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32908693A JP2896838B2 (en) | 1993-12-24 | 1993-12-24 | Molten steel manufacturing method |
| BR9406985-9A BR9406985A (en) | 1993-06-30 | 1994-06-30 | Process to produce steel in converter |
| KR1019950705930A KR0159180B1 (en) | 1993-06-30 | 1994-06-30 | Steel manufacturing method using converter |
| AU70831/94A AU680268B2 (en) | 1993-06-30 | 1994-06-30 | Steel manufacturing method using converter |
| EP94919835A EP0714989B1 (en) | 1993-06-30 | 1994-06-30 | Steel manufacturing method using converter dephosphorisation |
| PCT/JP1994/001070 WO1995001458A1 (en) | 1993-06-30 | 1994-06-30 | Steel manufacturing method using converter |
| ES94919835T ES2143547T3 (en) | 1993-06-30 | 1994-06-30 | STEEL MANUFACTURING METHOD USING DEPHOSPHORIZATION IN CONVERTER. |
| CA002166097A CA2166097C (en) | 1993-06-30 | 1994-06-30 | Process for producing steel by converter |
| DE69423630T DE69423630T2 (en) | 1993-06-30 | 1994-06-30 | STEEL MANUFACTURING IN CONVERTER WITH DEPHOSPHORUS LEVEL |
| CN94192953A CN1041843C (en) | 1993-06-30 | 1994-06-30 | Steel manufacturing method using converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32908693A JP2896838B2 (en) | 1993-12-24 | 1993-12-24 | Molten steel manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07179922A JPH07179922A (en) | 1995-07-18 |
| JP2896838B2 true JP2896838B2 (en) | 1999-05-31 |
Family
ID=18217466
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP32908693A Expired - Lifetime JP2896838B2 (en) | 1993-06-30 | 1993-12-24 | Molten steel manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2896838B2 (en) |
-
1993
- 1993-12-24 JP JP32908693A patent/JP2896838B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07179922A (en) | 1995-07-18 |
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