JP2946155B2 - How to use tundish continuously - Google Patents
How to use tundish continuouslyInfo
- Publication number
- JP2946155B2 JP2946155B2 JP5640893A JP5640893A JP2946155B2 JP 2946155 B2 JP2946155 B2 JP 2946155B2 JP 5640893 A JP5640893 A JP 5640893A JP 5640893 A JP5640893 A JP 5640893A JP 2946155 B2 JP2946155 B2 JP 2946155B2
- Authority
- JP
- Japan
- Prior art keywords
- tundish
- flux
- mgo
- caf
- cao
- 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 - Lifetime
Links
Landscapes
- Continuous Casting (AREA)
- Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、タンディッシュ連続使
用方法に関し、特に熱間で再使用する場合のタンディッ
シュ内スラグの排滓性を向上し、かつタンディッシュ耐
火物の損傷を軽微に留め、タンディッシュの繰り返し使
用回数を増す目的のタンディッシュ内添加フラックスと
該フラックスの添加方法にかかわるものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous use method of a tundish, and more particularly to a method of improving the slag discharge property of slag in a tundish when reusing hot, and minimizing damage to a refractory of the tundish. The present invention relates to a flux added to a tundish for the purpose of increasing the number of times the tundish is repeatedly used, and a method of adding the flux.
【０００２】[0002]
【従来の技術】連続鋳造用のタンディッシュを熱間で繰
り返し使用する操業が最近報告されてきている。タンデ
ィッシュを熱間で繰り返し使用すると耐火物コストの大
幅な削減はもとより、耐火物張り替えの作業要員の削減
も可能であり、いわゆる３Ｋ解消の対策としても注目を
浴びている。ところが、繰り返し使用していくと、タン
ディッシュ内耐火物面に残溶鋼や残スラグの排出残りが
累積され、タンディッシュ内に適正量の溶鋼を保持でき
なくなり、使用限界に達する。そこで、操業ではスラグ
の排出性を向上させるためにフラックスを添加し、繰り
返し使用回数の改善を図ってきた。2. Description of the Related Art An operation in which a tundish for continuous casting is repeatedly used hot has recently been reported. Repeated use of a tundish while hot can significantly reduce the cost of refractory materials, as well as reduce the number of workers required to replace refractory materials, and is attracting attention as a so-called 3K solution. However, when used repeatedly, the residual molten steel and residual slag are accumulated on the refractory surface in the tundish, so that an appropriate amount of molten steel cannot be retained in the tundish, and the service limit is reached. Therefore, in operation, flux has been added to improve the slag dischargeability, and the number of times of repeated use has been improved.
【０００３】タンディッシュ熱間で再使用する場合のタ
ンディッシュ内添加フラックスとして、「材料とプロセ
ス 第３巻（１９９０）Ｎｏ．４ ｐ．１２４」に発表
されているものがある。[0003] As a flux added to a tundish when it is reused in a tundish hot state, there is a flux disclosed in "Materials and Process, Vol. 3 (1990) No. 4, p. 124".
【０００４】該発表において、数３ 式を満たすフラッ
クス（ｂ）と数４ 式を満たすフラックス（ｃ）とを、
溶鋼注入前にタンディッシュ内に入れて、排滓性と溶損
を比較し、排滓性の観点からフラックス（ｂ）は好まし
いが、耐火物の溶損が大きく、フラックス（ｃ）を使用
し、排滓性の維持と耐火物溶損の低減を図っているとし
ている。In the presentation, flux (b) satisfying equation (3) and flux (c) satisfying equation (4) are defined as follows:
Before pouring the molten steel, put it in a tundish and compare the slag property and the erosion. Flux (b) is preferable from the viewpoint of the scum property, but the erosion of the refractory is large, and the flux (c) is used. According to the company, the aim is to maintain the rejectability and reduce the refractory erosion.
【０００５】[0005]
【数３】ＣａＯ／ＳｉＯ2 ＞１０ ＭｇＯ＝ｔｒ． Ａｌ2 Ｏ3 ＜３％ ＣａＦ2 ＝１０〜４０％## EQU3 ## CaO / SiO 2 > 10 MgO = tr. Al 2 O 3 <3% CaF 2 = 10 to 40%
【０００６】[0006]
【数４】ＣａＯ／ＳｉＯ2 ＞１０ ＭｇＯ＝２０％ Ａｌ2 Ｏ3 ＜３％ ＣａＦ2 ＝２０％## EQU4 ## CaO / SiO 2 > 10 MgO = 20% Al 2 O 3 <3% CaF 2 = 20%
【０００７】ところが、該フラックス（ｃ）を本発明者
らが使用したところ、タンディッシュ内の堆積物はフラ
ックス添加しない操業に比べて３分の１にはなるが、皆
無にはならず、繰り返し使用回数も６０回弱となった。However, when the present inventors used the flux (c), the amount of sediment in the tundish was reduced to one-third as compared with the operation without the addition of the flux, but it was not eliminated, but it was not repeated. The number of uses was also less than 60 times.
【０００８】[0008]
【発明が解決しようとする課題】本発明は、上記のタン
ディッシュの耐火物を損傷せずにタンディッシュ内残付
着物のさらなる減少を図り、タンディッシュの繰り返し
使用回数を増すことを目的にしたものであり、タンディ
ッシュ内添加フラックスとその添加方法について提供す
ることにある。SUMMARY OF THE INVENTION An object of the present invention is to further reduce the amount of deposits remaining in a tundish without damaging the refractory of the tundish and to increase the number of times the tundish is used repeatedly. An object of the present invention is to provide a flux added in a tundish and a method of adding the flux.
【０００９】[0009]
【課題を解決するための手段】本発明は上記課題を解決
するためになされたもので、その要旨とするところは、
以下の通りである。Means for Solving the Problems The present invention has been made to solve the above problems, and the gist of the present invention is as follows.
It is as follows.
【００１０】第一の本発明は、ＣａＯ、ＣａＦ2 、Ｍｇ
Ｏ、Ａｌ2 Ｏ3 、ＳｉＯ2 を含み、数１ 式を満たすタ
ンディッシュ内添加フラックスを、連続鋳造操業の末期
に、タンディッシュ内溶鋼面上に添加し、鋳造終了時に
タンディッシュ内残溶鋼とともに残スラグを排出し、タ
ンディッシュを熱間で繰り返し使用することを特徴とす
るタンディッシュ連続使用方法である。The first invention is directed to CaO, CaF 2 , Mg
At the end of the continuous casting operation, a flux containing O, Al 2 O 3 , SiO 2 and satisfying Equation 1 is added to the molten steel surface in the tundish, and at the end of casting, together with the residual molten steel in the tundish. This is a method for continuously using a tundish, characterized by discharging residual slag and repeatedly using the tundish while hot.
【００１１】[0011]
【数１】（ＣａＯ＋ＭｇＯ）／ＳｉＯ2 ＞１０ Ａｌ2 Ｏ3 ＜５％ １０％＜ＣａＦ2 ＜４０％ ＭｇＯ＜１０％(CaO + MgO) / SiO 2 > 10 Al 2 O 3 <5% 10% <CaF 2 <40% MgO <10%
【００１２】第２の本発明は、ＣａＯ、ＣａＦ2 、Ａｌ
2 Ｏ3 、ＳｉＯ2 を含み、数２ 式を満たすタンディッ
シュ内添加フラックスを、連続鋳造操業の末期に、タン
ディッシュ内溶鋼面上に添加し、鋳造終了時にタンディ
ッシュ内残溶鋼とともに残スラグを排出し、タンディッ
シュを熱間で繰り返し使用することを特徴とするタンデ
ィッシュ連続使用方法である。The second invention is directed to CaO, CaF 2 , Al
At the end of the continuous casting operation, the flux added to the tundish containing 2 O 3 and SiO 2 and satisfying Equation 2 was added to the molten steel surface in the tundish, and at the end of casting, the residual slag together with the remaining molten steel in the tundish was removed. This is a tundish continuous use method characterized by discharging and using the tundish repeatedly while hot.
【００１３】[0013]
【数２】ＣａＯ／ＳｉＯ2 ＞１０ Ａｌ2 Ｏ3 ＜５％ １０％＜ＣａＦ2 ＜４０％## EQU2 ## CaO / SiO 2 > 10 Al 2 O 3 <5% 10% <CaF 2 <40%
【００１４】[0014]
【作用】以下本発明を詳細に説明する。The present invention will be described below in detail.
【００１５】本発明者らは、タンディッシュの連続使用
試験を実施し、フラックス組成と添加時期を変更して最
適な条件を見出した。以下、タンディッシュ内付着堆積
物のフラックス組成依存性ならびに耐火物浸食度につい
て詳細に説明する。The present inventors conducted a continuous use test of a tundish, and found optimal conditions by changing the flux composition and the timing of addition. Hereinafter, the flux composition dependence of the deposits deposited in the tundish and the degree of refractory erosion will be described in detail.
【００１６】タンディッシュ内付着物の組成はＡｌ2 Ｏ
3 が約６０％、ＳｉＯ2 が約３０％、ＣａＯが約１０％
の組成であることを確認した。The composition of the deposit in the tundish is Al 2 O
3 about 60%, SiO 2 about 30%, CaO about 10%
It was confirmed that the composition was
【００１７】そこで、タンディッシュ内添加フラックス
としてはＣａＯ、ＣａＦ2 、ＭｇＯの三元系とした。Ｃ
ａＯには、付着物の原因として考えられるＡｌ2 Ｏ3 と
ＳｉＯ2 と混合して低融点化する機能を有していると考
えられる。これはＣａＯ−Ａｌ2 Ｏ3 −ＳｉＯ2 の三元
系状態図において、付着物にＣａＯを追加していき、そ
の組成を推測すると、丁度低融点域になるためである。Therefore, the flux added in the tundish was a ternary system of CaO, CaF 2 and MgO. C
The aO-, it is considered to have a function of lowering the melting point by mixing with Al 2 O 3 is considered as a cause of fouling and SiO 2. This is because, in the ternary phase diagram of CaO—Al 2 O 3 —SiO 2 , CaO is added to the adhered substance, and when its composition is estimated, the temperature becomes just low melting point.
【００１８】次に、ＣａＦ2 にはフラックス自体の溶融
を促進する機能がある。これは、ＣａＦ2 自体の融点が
１４２０℃と低く、そのものが優先して溶融し、他成分
の溶融を加速するためである。Next, CaF 2 has a function of accelerating the melting of the flux itself. This is because the melting point of CaF 2 itself is as low as 1420 ° C., which melts preferentially, and accelerates the melting of other components.
【００１９】また、ＭｇＯについては、一般にはＭｇＯ
濃度が高いほどＣａＦ2 などの浸食作用を緩和する作用
が報告されている。したがってＭｇＯをある程度含有す
る必要がある。As for MgO, generally, MgO
It has been reported that the higher the concentration, the less the erosion of CaF 2 and the like. Therefore, it is necessary to contain MgO to some extent.
【００２０】しかしながら、本発明者らがＭｇＯを２０
％含有したフラックスを使用していくと、タンディッシ
ュ付着物がＭｇＯを含む化合物に変化していることが判
明した。そこで、ＭｇＯの濃度について変更した試験を
実施すると、図１に示しているようにＭｇＯ含有量が低
いほどタンディッシュ付着物量が低減することが判明し
た。具体的には、ＭｇＯが１０％未満でタンディッシュ
付着物量が半減することが確認され、好ましくはＭｇＯ
が５％未満、最も好ましいのはＭｇＯ源として意図的に
添加しないフラックスである。However, the present inventors have proposed that MgO
%, It was found that the tundish deposit was changed to a compound containing MgO. Therefore, when a test in which the concentration of MgO was changed was carried out, as shown in FIG. 1, it was found that the lower the MgO content, the lower the amount of deposits on the tundish. Specifically, it was confirmed that the amount of deposits on the tundish was halved when the content of MgO was less than 10%,
Is less than 5%, most preferably a flux not intentionally added as a MgO source.
【００２１】また、ＭｇＯ含有量が低いほどタンディッ
シュ内耐火物の浸食が懸念されたが、図２に示すよう
に、連続鋳造の末期に、具体的には鋳造終了の５０分前
に、添加することで該耐火物の浸食は極めて少なくなる
ことが判明した。（図中、耐火物浸食度が小さいと溶損
大という意味である。）Further, as the MgO content was lower, there was a concern that the refractories in the tundish would erode. However, as shown in FIG. 2, at the end of continuous casting, specifically, 50 minutes before the end of casting, It has been found that the erosion of the refractory becomes extremely small. (In the figure, small refractory erosion means large erosion.)
【００２２】これは、フラックス添加後からスラグ排出
までの時間が短く、耐火物に対して浸食しやすいＣａＦ
2 の作用を軽減できたためであると考えられる。This is because the time from the addition of the flux to the discharge of the slag is short, and CaF is easily eroded by refractories.
It is considered that this was because the effect of 2 could be reduced.
【００２３】なお、フラックス添加時期については、添
加フラックスの粒度や溶鋼のスーパーヒート等の観点か
ら最適な時期があり、タンディッシュ溶鋼上面に浮遊し
ているスラグの排滓性を向上するのに必要な時間であれ
ば良く、通常は、連続鋳造終了の２０〜６０分前に添加
すれば良い。There is an optimum timing for adding the flux from the viewpoint of the particle size of the added flux and the superheat of the molten steel, which is necessary to improve the slag floating on the upper surface of the tundish molten steel. Any time may be used, and usually, the addition may be performed 20 to 60 minutes before the end of continuous casting.
【００２４】さらに、ＣａＯやＣａＦ2 の原料には不可
避的にＡｌ2 Ｏ3 、ＳｉＯ2 、ＭｇＯが不純物として含
有しており、上記目的のためには、Ａｌ2 Ｏ3 やＳｉＯ
2 を意図的に添加する必要はない。Furthermore, CaO or the the CaF 2 material is contained as unavoidable Al 2 O 3, SiO 2, MgO impurities, for the above purpose, Al 2 O 3 and SiO
It is not necessary to add 2 intentionally.
【００２５】[0025]
【実施例】本発明の実施例、比較例及び従来例を表１に
示した。EXAMPLES Examples of the present invention, comparative examples and conventional examples are shown in Table 1.
【００２６】タンディッシュ添加フラックスの組成と添
加時期を変更して、タンディッシュ内残付着物の量とタ
ンディッシュ耐火物の浸食状況を比較した。なお、タン
ディッシュ耐火物は８５％Ａｌ2 Ｏ3 のレンガを使用し
ている。The composition of the flux added to the tundish and the timing of addition were changed, and the amount of deposits remaining in the tundish and the erosion of the tundish refractory were compared. The tundish refractory uses 85% Al 2 O 3 brick.
【００２７】本発明の方法に従うと、タンディッシュ付
着物は従来例よりも少なく、かつ耐火物の浸食（溶損）
も軽微であることが確認できた。According to the method of the present invention, the amount of deposits on the tundish is smaller than in the conventional example, and the refractory is eroded (melted).
Was also slight.
【００２８】[0028]
【表１】 [Table 1]
【００２９】上記表１において、 （注１） タンディッシュ溶鋼量は約２０ｔｏｎ （注２） 鋳造初期から添加 （注３） 付着物量の指標が小さいほど付着物量が少な
いという意味 （注４） 耐火物浸食度が小さいと溶損大という意味 （注５） 鋳造が終了しタンディッシュ内溶鋼を排出し
た場合を１回とみなした。In the above Table 1, (Note 1) The amount of molten tundish steel is about 20 ton (Note 2) Added from the beginning of casting (Note 3) The smaller the index of the amount of attached material, the smaller the amount of attached material. (Note 4) Refractory Small erosion means large erosion (Note 5) The case where casting was completed and molten steel in the tundish was discharged was regarded as one time.
【００３０】[0030]
【発明の効果】本発明により、タンディッシュの耐火物
の浸食を抑制しながら、タンディッシュ内付着物を大幅
に減少せしめることが可能になる。したがって、タンデ
ィッシュを熱間で繰り返し使用する回数が増し、耐火物
コストの大幅な削減はもとより、耐火物張り替えの作業
要員の削減も可能であり、いわゆる３Ｋ解消の対策にも
なり、極めて工業上の利用価値の大きな発明である。According to the present invention, it is possible to greatly reduce the deposits in the tundish while suppressing the erosion of the refractory of the tundish. Therefore, the number of times the tundish is repeatedly used while hot is increased, so that it is possible not only to significantly reduce the cost of refractories but also to reduce the number of workers who need to replace refractories, which is a measure to eliminate the so-called 3K. This is an invention with a large utility value.
【図１】フラックス中のＭｇＯ含有量とタンディッシュ
付着物量との関係を示す図である。FIG. 1 is a graph showing the relationship between the MgO content in a flux and the amount of deposits on a tundish.
【図２】フラックス添加時期とタンディッシュ耐火物浸
食度との関係を示す図である。FIG. 2 is a graph showing the relationship between the timing of adding a flux and the degree of erosion of a tundish refractory.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平１−107948（ＪＰ，Ａ) 特開 昭59−16659（ＪＰ，Ａ) 特開 平４−305348（ＪＰ，Ａ) 特開 平４−274866（ＪＰ，Ａ) 特開 昭61−86055（ＪＰ，Ａ) (58)調査した分野(Int.Cl.6，ＤＢ名) B22D 11/10 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-1-107948 (JP, A) JP-A-59-16659 (JP, A) JP-A-4-305348 (JP, A) JP-A-4-107348 274866 (JP, A) JP-A-61-86055 (JP, A) (58) Fields investigated (Int. Cl. 6 , DB name) B22D 11/10
Claims (2)
2 Ｏ3 、ＳｉＯ2 を含み、数１ 式を満たすタンディッ
シュ内添加フラックスを、連続鋳造操業の末期に、タン
ディッシュ内溶鋼面上に添加し、鋳造終了時にタンディ
ッシュ内残溶鋼とともに残スラグを排出し、タンディッ
シュを熱間で繰り返し使用することを特徴とするタンデ
ィッシュ連続使用方法。 【数１】（ＣａＯ＋ＭｇＯ）／ＳｉＯ2 ＞１０ Ａｌ2 Ｏ3 ＜５％ １０％＜ＣａＦ2 ＜４０％ ＭｇＯ＜１０％1. CaO, CaF 2 , MgO, Al
At the end of the continuous casting operation, the flux added to the tundish containing 2 O 3 and SiO 2 and satisfying Equation 1 is added to the molten steel surface in the tundish, and at the end of the casting, the residual slag together with the remaining molten steel in the tundish. A method for continuously using a tundish, comprising discharging and repeatedly using the tundish while hot. (CaO + MgO) / SiO 2 > 10 Al 2 O 3 <5% 10% <CaF 2 <40% MgO <10%
2 を含み、数２ 式を満たすタンディッシュ内添加フラ
ックスを、連続鋳造操業の末期に、タンディッシュ内溶
鋼面上に添加し、鋳造終了時にタンディッシュ内残溶鋼
とともに残スラグを排出し、タンディッシュを熱間で繰
り返し使用することを特徴とするタンディッシュ連続使
用方法。 【数２】ＣａＯ／ＳｉＯ2 ＞１０ Ａｌ2 Ｏ3 ＜５％ １０％＜ＣａＦ2 ＜４０％2. CaO, CaF 2 , Al 2 O 3 , SiO
At the end of the continuous casting operation, a flux added to the tundish that satisfies Equation 2 is added to the molten steel surface in the tundish, and at the end of casting, the residual slag is discharged together with the remaining molten steel in the tundish. A method for continuously using a tundish, wherein the method is repeatedly used while hot. ## EQU2 ## CaO / SiO 2 > 10 Al 2 O 3 <5% 10% <CaF 2 <40%
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5640893A JP2946155B2 (en) | 1993-02-23 | 1993-02-23 | How to use tundish continuously |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5640893A JP2946155B2 (en) | 1993-02-23 | 1993-02-23 | How to use tundish continuously |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06246408A JPH06246408A (en) | 1994-09-06 |
| JP2946155B2 true JP2946155B2 (en) | 1999-09-06 |
Family
ID=13026340
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|---|---|---|---|
| JP5640893A Expired - Lifetime JP2946155B2 (en) | 1993-02-23 | 1993-02-23 | How to use tundish continuously |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100380745B1 (en) * | 1998-12-24 | 2004-05-31 | 주식회사 포스코 | Flux applying to molten steel in tundish |
| KR20010047713A (en) * | 1999-11-23 | 2001-06-15 | 이구택 | Acclerating material for discharging residue in hot recycled tundish and method for discharging by using it |
| KR100490741B1 (en) * | 2000-12-22 | 2005-05-24 | 주식회사 포스코 | method of manufacturing stainless steel having good cleanliness utilizing tundish flux and the tundish flux |
| JP5437945B2 (en) * | 2010-07-29 | 2014-03-12 | 株式会社神戸製鋼所 | Method for suppressing deposits in hot repeated tundish |
| CN107052289B (en) * | 2017-05-09 | 2019-06-28 | 唐山不锈钢有限责任公司 | The Adding Way of the tundish covering flux poured is opened for continuous casting |
| KR102288415B1 (en) * | 2020-03-18 | 2021-08-10 | 주식회사 포스코 | Tundish flux and casting method using the same |
-
1993
- 1993-02-23 JP JP5640893A patent/JP2946155B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06246408A (en) | 1994-09-06 |
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