JPS5834123A - Molten metal treatment vessel - Google Patents

Abstract

PURPOSE:To cause no local wear and tear of a refractory body in the circumference of a nozzle, by constituting so that the refractory body in the circumference of a gas blow-in nozzle in a molten metal contains alumina and carbon of a specific quantity. CONSTITUTION:In the circumference of a gas blow-in nozzle (c) in a molten metal, a refractory body which has alumina >=30wt% (hereinafter all the same) in aggregate and has added 3-40% carbon is placed. For instance, sleeve brick 6 is constituted of 80% alumina and 20% carbon, and in order to cope with spalling and thermal stress cracking, spalling resistance is taken into consideration. Also, tuyere brick 7 is constituted of 85% alumina and 15% carbon, and in order to cope with air bubble moving-back and a high temperature flow, strength is taking into consideration. Also, as for its circumference 9, alumina magnesia compound spinel carbon brick consisting of 56% alumina, 22% magnesia and 13% carbon is used, and in order to cope with contact with a high temperature slag rolled in by an agitating flow, corrosion resistance is taken into consideration.

Description

【発明の詳細な説明】 本発明は耐スポール性にすぐれ１機械強度が高く、寿命
の長い溶融金属内ガス吹込ノズル周辺用レンガを配設し
九溶融金゛属処履容器を提案するものである。[Detailed Description of the Invention] The present invention proposes a molten metal processing container in which bricks are provided around the nozzle for blowing gas into the molten metal, which has excellent spall resistance, high mechanical strength, and long life. be.

一般的に溶融金属処理容器１例えば、転炉、脱ガス槽、
取鍋畔の浴内に用いるガス吹込ノズル周辺の耐火レンガ
材質としては、塩基性スラグに強いマダネシアクロム質
、マグネシアドロｉイト質の焼成レンガあるいは前記の
耐スポール性を改善し九不焼成の！ダネシアカーボン質
、マグネシア・ドロマイト・カーボン質レンガが用いら
れている。Generally, the molten metal processing vessel 1 is, for example, a converter, a degassing tank,
The materials for the refractory bricks around the gas injection nozzle used in the bath on the side of the ladle include fired bricks made of madanesia chromium or magnesia doroite, which are resistant to basic slag, or the above-mentioned fired bricks with improved spall resistance. ! Danesia carbon bricks and magnesia dolomite carbon bricks are used.

（以上を称してマグネシア系レンガとする。）”ここで
不焼成マグネシアカーボン質、マダネシアド四マイトカ
ーｌン質レンガは、各骨材を有機系バインダーとと４に
混錬成形し、これを比較的量温で加熱し、硬化させる製
造プロセスである。(The above is referred to as a magnesia-based brick.) Here, unfired magnesia carbon and madanesia carbonite bricks are made by kneading and molding each aggregate with an organic binder, and then relatively This is a manufacturing process that involves heating and curing at a certain temperature.

而して、前記塩基性スラグに強いマグネシア系レンガに
おいては、ＩＩ鋼吊用ガス吹込ノズル周辺耐火線層とし
て使用されていゐが、一般的には（１）　　マグネシア
系骨材は、ｌｌｌＰＩＭ率が１０００ｔｌ’でｌ！ＮＳ
以上と大きく耐スポール性が−い。Therefore, in the magnesia-based brick that is resistant to basic slag, it is used as a refractory layer around the gas injection nozzle for hanging II steel, but generally (1) the magnesia-based aggregate has a lll PIM rate. 1000tl'! N.S.
As mentioned above, the spall resistance is greatly improved.

（２）　　為温下では、マグネシアと炭素とが反応し。(2) At temperature, magnesia and carbon react.

マグネシウムと一酸化炭素となるマグネシアカーボン反
応が斃生子る。更（吹込ガスとの接触により内部分ＩＥ
が低下するととＫよ）該反応が顕著となシ高温で安定性
に欠け、損耗が太き（なる。The result is a magnesia carbon reaction that produces magnesium and carbon monoxide. change (internal part IE due to contact with blown gas)
When K decreases, the reaction becomes more pronounced, the product lacks stability at high temperatures, and wear and tear increases.

（３）　　″Ｖグネシアカーボン質、Ｔグネシアドロマ
イトカーボン質、不焼成レンガは使用温度において有機
系バインダーが揮発する為、第１図に示す如く使用中に
は強度が低下する。(3) Since the organic binder of V gnesia carbon, T gnesia dolomite carbon, and unfired bricks evaporates at the operating temperature, their strength decreases during use, as shown in FIG.

（４）　　上記（１）〜（３）全改善する為、高価な電
融マグネシア骨材を使用するので製品価格が高価である
。(4) In order to improve all of the above (1) to (3), an expensive electrofused magnesia aggregate is used, so the product price is high.

等の問題がある。There are other problems.

具体的には、底吹、上底吹転炉ガス吹込ノズル周辺に使
用されている不焼成Ｍｇ０−Ｃレンガの溶損を第２図Ｃ
）、（ロ）によに説明する。尚、第２図（イ）は、内管
ＩＩＩから反応性ガス、内管Ｉｆｉと外管Ｏｕ間から冷
却ガスを吹込む二重管式のノズルＣを用いた例であり、
第２図（ロ）は不活性ガスを吹込む単管のノズルＣ′を
用い九例である。Specifically, the melting loss of the unfired Mg0-C bricks used around the gas injection nozzles of bottom-blown and top-bottom-blown converters is shown in Figure 2C.
), (b) to explain. In addition, FIG. 2 (a) is an example using a double-pipe nozzle C that blows reactive gas from the inner tube III and cooling gas from between the inner tube Ifi and the outer tube Ou.
FIG. 2(b) shows nine examples using a single-pipe nozzle C' for blowing inert gas.

図に示す如く操業中に発生する損耗は、（１）冷却ガス
又は不活性ガスＧＫよる耐火物への直＊＊触による熱的
スポーリングｌの発生（１）熱応力による割れ２脅生 （１）更に３の気泡後退によシ耐大物ｂｔ直接叩（現象
（以後底叩きと称す、）による損傷。As shown in the figure, the wear and tear that occurs during operation is (1) occurrence of thermal spalling due to direct contact of cooling gas or inert gas GK to the refractory (1) cracking due to thermal stress (2) 1) Furthermore, damage caused by direct hitting (phenomenon (hereinafter referred to as bottom hitting)) of large objects due to the receding of the bubbles in step 3.

（ｆｆ）反応によシ生じた高温流４が耐火物に接触する
為の！ダネシアカーボン反応による損傷勢。(ff) Because the high temperature flow 4 generated by the reaction comes into contact with the refractory! Damage caused by Danesia Carbon reaction.

以上（Ｉ）〜（Ｎ）が主な損耗要因であり、これ等によ
６ｆ３図に示す如くノズルＣ周辺に局部損耗８が生じる
。The above (I) to (N) are the main causes of wear, and these cause local wear 8 around the nozzle C as shown in Figure 6f3.

こＯようにガス吹込ノズル周辺の耐火レンガは匍ＩＩＫ
比し著しく局部損耗が大きい為、再三の補修が必要とな
るが、補修のみで対応するのは操業上眼界を生じ、繁雑
で多大な時間を要する炉底交換によ〉転炉全体の寿命鴬
長を実権している。しかしながら多大な補修材の使用、
廃集レンガによる炉材原単位の上昇、交換の為の長時間
休止は避けられず他意性の低下は免れ得ないのが現状で
ある。The fireproof bricks around the gas injection nozzle are made of IIK.
As the local wear and tear is significantly larger than that, repeated repairs are required, but repairing alone will cause problems in operation, and the complicated and time-consuming hearth bottom replacement will shorten the life of the entire converter. He has real power over the president. However, the use of a large amount of repair materials,
The current situation is that the consumption of waste bricks increases the unit consumption of furnace materials, and that long downtime for replacement is unavoidable, resulting in a decrease in otherness.

本発明はかかるマグネシア系レンガの問題点を解決すべ
く種々検討を行つ九結果、溶融金属内ガス吹込ノズル周
辺は、第２図ヒ）、（ロ）および第４図（閂■は上底吹
き転炉の概念図で、第２図（イ）は同図の部分詳細図で
ある。）に示す如く、＃鋼に浸漬され、更に冷却ガスの
影響による凝固鉄（以後マツシュルーム１と称す）周囲
よシ冷却ガスＧが噴出している為、精錬段階ではノズル
（：：、ｅ’周辺の耐火レンガｂとスラグの接触社すく
ない。尚。The present invention has been made after various studies to solve the problems of magnesia-based bricks, and as a result, the area around the gas injection nozzle in the molten metal is This is a conceptual diagram of a blowing converter, and as shown in Figure 2 (A), which is a partial detailed diagram of the same figure, iron is immersed in # steel and further solidified under the influence of cooling gas (hereinafter referred to as Matushroom 1). Since the cooling gas G is spewing out around the area, there is little contact between the refractory brick B and the slag around the nozzle (::, e') during the refining stage.

−）！！４図中、ＡＦｉスラグ層（温度１６００ｃ以上
）。−)! ! In Figure 4, AFi slag layer (temperature 1600C or higher).

Ｂはスラグ層火点（温度３０００ｔｌｌ’）、Ｂ’は火
点（温度２６００Ｃ）である。B is the slag layer fire point (temperature 3000 tll'), and B' is the fire point (temperature 2600 C).

又、その他、受銑、出鋼、スラグコーディング等の鳩舎
は、ノズＡ／ｊｌｉ１辺レンガとスラグとの接触状況紘
、 （１）湯面通過時の接触で、数秒の極短時間である。In addition, in pigeonholes for pig iron receiving, tapping, slag coating, etc., the contact status between the brick on one side of the nozzle A/jli and the slag is as follows: (1) The contact occurs when the molten metal passes through the surface, and the contact is for a very short time of several seconds.

（２）炉壁のスラグコーティング時での接触で。(2) Contact during slag coating of furnace walls.

スラグ温度は１，２００〜１，３００Ｃと低い。The slag temperature is as low as 1,200-1,300C.

という事実を知見した。I discovered this fact.

この事実にたって本発明者畔は１強度、耐スポール性が
優れ【いるが、塩基性スラグに対する耐食性が低いこと
から、一般的には塩基性スラグが存在する製鋼炉容器で
の使用は困難とされてい九アル電ナカーボン質およびア
ルミナマグネシアカーボン質（マグネシア５０重量係以
下添加）ならびにアル建ナマグネシア系スピネルカーボ
ン質（アル電すとして３０重重量風上を含有）および必
要に応じ【これ等に炭化珪素を３０重量％以下添加した
通常のアルミナ系不焼成レンガを溶融金属内βス吹込用
ノズル周辺に使用することを試み九結果、上記スッグの
影響は実質的に無害に等しいことが判明した。Based on this fact, the inventor's slag has excellent strength and spalling resistance, but because it has low corrosion resistance against basic slag, it is generally difficult to use it in steelmaking furnace vessels where basic slag exists. Aldena carbonaceous materials, alumina magnesia carbonaceous materials (adding up to 50% magnesia by weight), alumina magnesia spinel carbon materials (containing 30% by weight windward as aluminum) and carbonized materials as necessary. An attempt was made to use an ordinary alumina-based unfired brick containing 30% by weight or less of silicon around the nozzle for injecting β-sulfur into the molten metal, and as a result, it was found that the effect of the sag was virtually harmless.

本発明は上記知見をもとになされたものでその重量鴫以
上４０重量僑以下の炭素を添加し九耐火物を配設した溶
融金属処理容器にある。The present invention has been made based on the above-mentioned knowledge, and is directed to a molten metal processing vessel in which carbon is added in a weight range of 10 to 40 parts and a refractory is disposed therein.

この発明で用いる骨材にアル建すｔ３０重量重量上有し
３〜４０重量係の炭素を添加し丸前記アル建す系不情或
しンｙ＃ｉ、４？に新な組成限定を設け＊ｌ）ｅ嬬なく
、広く、連続−造工糧等、高温スラダとは接触がなく溶
鋼とのみ接触する部位に用いられている公知のアルミナ
系不焼成レンガの範−を出るものではない。The aggregate used in this invention has 30% to 40% carbon added to the aggregate to be used in the present invention. New compositional limitations have been set for *l) e) The range of well-known alumina-based unfired bricks that are widely used in areas that do not come into contact with high-temperature slurry but only with molten steel, such as continuous and continuous production, has been established. - It is not something that comes out.

本発明は、これを、上記の知見にもとづいて数秒の極短
時間の高温スラグとの接触および、数秒を超える接触ス
ラグの低温状鰺から、アルＺす系不焼成レンガの最も弱
点と考えられ使用を避けていた溶融金属処理容器の金属
浴内ガス吹込ノズルの周辺の新用途に適用したものであ
って、これによって従来用いられ【いた前記マグネシア
系レンガの問題点を単に解消したばかシでなく溶損指数
（ｍ／ｃｈ　）　を約０．７弱に低減し、寿命を約Ｌ４
倍に延長せしめたものである。Based on the above-mentioned knowledge, the present invention considers this to be the weakest point of AlZ-based unfired bricks, due to the contact with high-temperature slag for an extremely short period of several seconds and the low-temperature state of the contact slag for more than several seconds. This was applied to a new application around the gas blowing nozzle in the metal bath of the molten metal processing vessel, which had been avoided, and was a foolproof method that simply solved the problems of the magnesia bricks previously used. It reduces the erosion index (m/ch) to just under 0.7 and reduces the service life to about L4.
It has been doubled in length.

以上の内容に基づいて転炉炉底に用い九本発明の一実論
例を牙暮図に示す。Based on the above content, a practical example of the present invention applied to the bottom of a converter furnace is shown in the figure below.

図に示すスリーブレンガ６にはアルンナ８０重量係、炭
素２０重量係で前記第２図に示すスポーリング１と熱応
力割れ２に対処して、耐スポーリング性ｔ−考慮し１羽
口レンガ７については前記第２図に示す気泡後退３と高
温流４に対処して、耐強度を考慮し、アルミナ８５−量
鳴、炭素１１重量％を使用している。更にその周辺９に
ついては。The sleeve brick 6 shown in the figure is made of Arunna 80 weight ratio and carbon 20 weight ratio to cope with spalling 1 and thermal stress cracking 2 shown in FIG. In order to deal with the bubble recession 3 and high-temperature flow 4 shown in FIG. 2, 85% alumina and 11% by weight carbon are used in consideration of strength resistance. Furthermore, regarding the surrounding area 9.

アルンナ５６重量％、マグネシア２２重量優、縦索１８
重量憾のアル電ナマグネシア系スピネルカーボンレンガ
を使用し攪拌流によシ巻込まれた高温スラグとの接触に
対処して、耐食性を考慮した。Arunna 56% by weight, magnesia 22% by weight, longitudinal cable 18%
Corrosion resistance was considered by using a heavy aludenomamagnesia spinel carbon brick to cope with contact with high-temperature slag engulfed by the agitation flow.

これ等の結果ノズル周辺レンガであるスリーブレンガ６
および羽口レンガ７ならびに周辺レンガ９の溶損指数（
ｍ／ｃｈ　）　Ｆｉそれぞれ０．４で安定し炉寿命０ｚ
ｏｏｏｃｈの使用に耐えて余命を示したｅ以上１本尭明
によれば、溶融金属内ノズル周辺の耐火物は局部損耗が
皆無となシ、補修が不要となって、炉底周囲のレンガと
の損耗速度が略均等となり、これによシ溶融金属処理容
器の寿命中にシけるノズル周辺レンガの補修による操炉
停止がなくな）、犬山な生産コスト低減が可能となる等
。As a result of these, sleeve brick 6 which is the brick around the nozzle
and erosion index of tuyere brick 7 and surrounding brick 9 (
m/ch) Fi is stable at 0.4 each, and the furnace life is 0z
According to Takaaki, there is no local wear and tear on the refractory around the nozzle inside the molten metal, and there is no need for repair, and the bricks around the bottom of the furnace are in good condition. The rate of wear and tear becomes almost uniform, which eliminates the need to stop the furnace operation due to repair of bricks around the nozzle that break during the life of the molten metal processing container), making it possible to significantly reduce production costs.

生産上多大の効果が得られる。Great effects on production can be obtained.

【図面の簡単な説明】[Brief explanation of drawings]

才１図はＭｆＯ−Ｃレンガの熱間強度を示すグラフ。 第２図ｋ）、（ｍは、上底吹転炉炉底のガス吹込部例を
夫々示す拡大断面説明図。 第３図は、ガス吹込ノズル周辺の局部損耗状態を示す断
面説明図、 第４図は上底吹転炉の概念図。 才５図は１本発明の一実緒例を示す要部断面説明図であ
る。 図におい【。 畠：マツシュルーム、ｂ二ノズル周辺の耐火レンガ、Ｃ
；ノズル、６：スリーブレンガ、７：羽口レンガ、９：
羽口レンガの周辺のレンガ。 代理人弁理士　秋　沢　政　光 他２名 ｌ め１図 毛４国 名３目 Ｃ 異５図 θ １１８Figure 1 is a graph showing the hot strength of MfO-C bricks. Figures 2 (k) and (m) are enlarged cross-sectional explanatory diagrams showing examples of the gas injection part at the bottom of the top-bottom blowing converter. Figure 4 is a conceptual diagram of a top-bottom blowing converter. Figure 5 is a cross-sectional explanatory diagram of a main part showing an example of the present invention.
; Nozzle, 6: Sleeve brick, 7: Tuyere brick, 9:
Bricks around the tuyere bricks. Representative Patent Attorney Masamitsu Akizawa and 2 others l Me 1 Figure 4 Country name 3 C Different 5 Figure θ 118

Claims (3)

【特許請求の範囲】[Claims] （１）　　溶融金属内ガス吹込ノズル周辺に、骨材にア
ルｉナを３０重重量風上を有し、３重量僑以上４０重量
優以下の炭素を添加し九耐火物を配設したことを特徴と
する溶融金属処理容器。(1) Around the nozzle for blowing gas into the molten metal, 9 refractories are placed around the nozzle for blowing gas into the molten metal. Characteristic molten metal processing container. （２）前記耐火１１１にマグネシアｔ−５０重量４以下
を添加し良ことを特徴とする特許請求の範囲才１項記載
の溶融金属処理容器。(2) The molten metal processing vessel according to claim 1, wherein 4 or less by weight of magnesia T-50 may be added to the refractory 111. （３）　　前記耐火物に炭化珪素３０重重量風下を添加
し九ことを特徴とする特許請求の範囲才１項又は第２項
記載の溶融金属処理容器。(3) The molten metal processing vessel according to claim 1 or 2, characterized in that 30 g of silicon carbide is added to the refractory.