JP2001059114A - Porous plug - Google Patents
Porous plugInfo
- Publication number
- JP2001059114A JP2001059114A JP11231967A JP23196799A JP2001059114A JP 2001059114 A JP2001059114 A JP 2001059114A JP 11231967 A JP11231967 A JP 11231967A JP 23196799 A JP23196799 A JP 23196799A JP 2001059114 A JP2001059114 A JP 2001059114A
- Authority
- JP
- Japan
- Prior art keywords
- raw material
- gas
- porous plug
- molten steel
- strength
- 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
- Compositions Of Oxide Ceramics (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Furnace Charging Or Discharging (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、取鍋等の底に取り
付けられ、溶鋼攪拌に伴う溶鋼温度の均一化、溶鋼成分
の均質化、２次精錬効果の向上及び非金属介在物の浮上
除去等のために溶鋼中にガスを吹き込むためのポーラス
プラグに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a bottom of a ladle or the like, and makes the molten steel temperature uniform, homogenizes molten steel components, improves secondary refining effect, and removes nonmetallic inclusions by floating molten steel. The present invention relates to a porous plug for blowing gas into molten steel for the purpose of, for example, the following.
【０００２】[0002]
【従来の技術】通常ポーラスプラグは繰り返し使用さ
れ、そのライフはおよそ５〜３０回である。このポーラ
スプラグで最も重要な特性は、バブリング信頼性であ
る。バブリング信頼性とは、必要な時に溶鋼中へ必要な
量のガスを必ず吐出することができることである。バブ
リング信頼性が低く、いざと言う時にガスを吐出するこ
とができないと、溶鋼成分や溶鋼温度を均一にすること
ができないため、製造工程が中断してしまい溶鋼を再び
転炉や電気炉に戻さなければならなくなる。2. Description of the Related Art Generally, a porous plug is used repeatedly and its life is about 5 to 30 times. The most important property of this porous plug is bubbling reliability. The bubbling reliability means that a required amount of gas can be always discharged into molten steel when required. If the bubbling reliability is low and the gas cannot be discharged at the time of emergency, the molten steel composition and the molten steel temperature cannot be made uniform, interrupting the manufacturing process and returning the molten steel to the converter or electric furnace again. Have to be.
【０００３】一般的に、ポーラスプラグは取鍋の底に取
り付けられ、まず転炉や電気炉から溶鋼を受鋼する時に
溶鋼の攪拌のためにガスを吐出する。その後、ガス吹き
を中断して鍋を移動し、取鍋精錬時に再びガスを吐出す
る。そして、精錬後の鋳造中の約６０分間位はガスを吐
出しない。[0003] Generally, a porous plug is attached to the bottom of a ladle and first discharges gas for stirring molten steel when the molten steel is received from a converter or an electric furnace. Thereafter, the gas blowing is interrupted, the pot is moved, and gas is discharged again during ladle refining. Gas is not discharged for about 60 minutes during casting after refining.
【０００４】このようなポーラスプラグの使われ方で問
題となるのは、ガス吐出の中断に伴う問題である。すな
わちガス吐出の中断中に、ポーラスプラグの気孔中へ稼
働表面から溶鋼が浸入し凝固して溶鋼浸潤層を形成す
る。そして、この溶鋼浸潤層のためガスが吐出しにくく
なってしまう。よって、中断後必要なガス量を吐出する
ためには、ポーラスプラグ表面の溶鋼浸潤層をガス圧で
吹き飛ばす必要がある。ガス圧でポーラスプラグの溶鋼
浸潤層が吹き飛ぶと、新しい耐火物の表面が露出するの
で、満足する流量が確保できる。A problem in the use of such a porous plug is a problem associated with interruption of gas discharge. That is, while the gas discharge is interrupted, the molten steel penetrates into the pores of the porous plug from the working surface and solidifies to form a molten steel infiltration layer. And it becomes difficult to discharge gas due to the molten steel infiltration layer. Therefore, in order to discharge a necessary gas amount after the interruption, it is necessary to blow off the molten steel infiltration layer on the surface of the porous plug with gas pressure. If the molten steel infiltration layer of the porous plug is blown off by the gas pressure, the surface of the new refractory is exposed, so that a satisfactory flow rate can be secured.
【０００５】また、鋳造後取鍋が空になると、次の受鋼
に備えてポーラスプラグにガスを流して所定の流量が確
保されているかポーラスプラグの通気性能を確認する作
業を行う。しかしながら、流量が不足している場合に
は、表面を酸素洗浄する必要がある。この作業は、ポー
ラスプラグ内にガス圧をかけた状態でポーラスプラグの
先端に向けて鉄パイプから酸素を吹き付けると、酸素と
溶融した酸化鉄によりポーラスプラグの溶鋼浸潤層を溶
かし、新しい表面を露出させるものである。この作業
は、高熱作業でしかも鍋の底が見にくく確実に洗浄をす
ることは非常に難しく、洗浄が不十分で次の使用時にガ
ス吐出不良になることもある。When the ladle is empty after casting, gas is supplied to the porous plug in preparation for the next steel receiving operation to check whether a predetermined flow rate is secured or not and check the ventilation performance of the porous plug. However, when the flow rate is insufficient, the surface needs to be cleaned with oxygen. In this work, when gas is applied inside the porous plug and oxygen is blown from the iron pipe toward the tip of the porous plug, the molten steel infiltration layer of the porous plug is melted by oxygen and molten iron oxide, exposing a new surface It is to let. This operation is a high-temperature operation, and it is very difficult to reliably clean the bottom of the pot, and it is very difficult to clean the pan.
【０００６】このような、ポーラスプラグにおけるガス
の再吐出に際しての不都合を解消する手段が、従来から
種々提案されている。Various means have been conventionally proposed to solve such inconvenience in re-discharging the gas in the porous plug.
【０００７】例えば、特開平２−３０７８６３号公報に
は、ガス吐出不良の原因となる溶鋼浸潤層の厚みを小さ
くするために、粒径１〜０．３ｍｍのアルミナ球状原料
を使用して気孔径の分布幅を狭くして溶鋼の浸入を少な
くすることが記載されている。For example, Japanese Unexamined Patent Publication (Kokai) No. 2-307863 discloses that in order to reduce the thickness of a molten steel infiltration layer which causes gas discharge defects, a pore diameter of 1 to 0.3 mm is used for an alumina spherical raw material. It is described that the distribution width of steel is narrowed to reduce the penetration of molten steel.
【０００８】また、特公平７−７４０９１号公報には、
通気性耐火物にジルコニアムライト原料を使用し、これ
によって、ジルコニアムライトとメタル及びスラグとの
反応によって粘性を向上せしめて溶鋼の浸入を軽減する
ことが記載されている。In Japanese Patent Publication No. 7-74091,
It is described that a zirconia mullite raw material is used as a breathable refractory material, whereby the viscosity of the zirconia mullite is increased by the reaction of the zirconia mullite with metal and slag to reduce the infiltration of molten steel.
【０００９】このような対策によって、ポーラスプラグ
の耐用性が向上し安定使用できる。しかしながら、通気
率が２〜５ＣＧＳと高い通気性耐火物を使用し、ガス流
量を多くする場合には、通常よりも溶鋼浸潤層が厚く残
り、使用時にガス吐出が困難になったり、酸素洗浄に非
常に時間を要する場合があり、必要時にガスを吐出でき
るバブリング信頼性が低下する。With such measures, the durability of the porous plug is improved and the porous plug can be used stably. However, when using a gas permeable refractory having a high air permeability of 2 to 5 CGS and increasing the gas flow rate, the molten steel infiltration layer remains thicker than usual, making it difficult to discharge gas at the time of use or for oxygen cleaning. In some cases, it takes a very long time, and the bubbling reliability for discharging the gas when needed is reduced.
【００１０】通常、通気性耐火物の通気率は、成形時の
加圧力あるいは配合の粒度構成でコントロールすること
ができる。精錬時に多くのガスを吐出する必要がある場
合には、成形時の加圧力を弱くしたりあるいは粒径の大
きい原料粒子を使用したりして通気率の高い通気性耐火
物を製造する。ガスの吐出量が少なくても良い場合に
は、逆に加圧力を強くしたり粒径の小さい原料粒子を使
用したりしている。したがって、通気量が多い条件で使
用する場合には気孔径が大きくなるため、溶鋼浸潤層が
厚くなる。溶鋼浸潤層が厚くなると、使用時にこの部分
が吹き飛びにくくなったりあるいは酸素洗浄に時間を要
する。Normally, the permeability of the breathable refractory can be controlled by the pressing force during molding or the particle size of the compound. When it is necessary to discharge a large amount of gas during refining, a gas-permeable refractory having a high air permeability is manufactured by weakening the pressing force during molding or using raw material particles having a large particle diameter. When the gas discharge amount may be small, conversely, the pressing force is increased or raw material particles having a small particle size are used. Therefore, when used under the condition of a large amount of ventilation, the pore diameter becomes large, and the molten steel infiltration layer becomes thick. When the molten steel infiltration layer is thick, this portion is hardly blown off during use, or it takes time for oxygen cleaning.
【００１１】さらには、従来の通気性耐火物は、高強度
でしかも耐スポーリング性に優れたものとするために１
７００℃程度の高温で焼成することが、より一層溶鋼浸
潤層をガス圧のみで吹き飛ばすことが困難になる。Further, conventional breathable refractories are required to have high strength and excellent spalling resistance.
Firing at a high temperature of about 700 ° C. makes it more difficult to blow off the molten steel infiltration layer only by gas pressure.
【００１２】[0012]
【本発明が解決しようとする課題】本発明が解決しよう
とする課題は、ガス吐出量が多い条件で使用されてもバ
ブリング信頼性の高いポーラスプラグを提供することで
ある。SUMMARY OF THE INVENTION It is an object of the present invention to provide a porous plug having high bubbling reliability even when used under a condition where a large amount of gas is discharged.
【００１３】[0013]
【課題を解決するための手段】ガス吐出量が多い条件で
使用されてもバブリング信頼性の高いポーラスプラグを
得るための条件は、ガスの再吐出に際して溶鋼浸潤層を
ガス圧で吹き飛びやすくすることである。A condition for obtaining a porous plug having high bubbling reliability even when used under a condition where the gas discharge amount is large is that the molten steel infiltration layer is easily blown off by the gas pressure when the gas is discharged again. It is.
【００１４】一旦使用した後のポーラスプラグは、溶鋼
浸潤層と未浸潤部との境界付近には熱膨張率の差から亀
裂が入っており、これにガスの吐出に際してのガス圧を
かけると、この亀裂を基点に先端部が吹き飛ぶものと考
えられる。The porous plug, once used, has a crack near the boundary between the molten steel infiltrated layer and the uninfiltrated portion due to the difference in the coefficient of thermal expansion. It is considered that the tip part blows off based on the crack.
【００１５】本発明は、溶鋼浸潤層を吹き飛びやすくす
るためには、ポーラスプラグを形成する通気性耐火物の
強度を下げることによって達成できるという着想の下で
完成した。The present invention has been completed under the idea that the molten steel infiltration layer can be easily blown off by reducing the strength of the gas-permeable refractory forming the porous plug.
【００１６】この強度の指標として熱間での曲げ強度及
び圧縮強度に着目した。従来のポーラスプラグに使用さ
れる熱間強度は、例えば特開平１０−１８２２５９号公
報では１４００℃で１２〜１４ＭＰａが良いとされてい
るが、この強度では溶鋼浸潤層が吹き飛びにくい。しか
しながら、従来材質で成形圧や粒度構成を変えて単に強
度を下げるだけでは耐用性が低下するために、耐用性と
のバランスをとることが重要である。As an index of the strength, attention was paid to the bending strength and the compression strength during hot working. For example, Japanese Patent Application Laid-Open No. H10-182259 states that the hot strength used for a conventional porous plug is 12 to 14 MPa at 1400 ° C., but the strength at which the molten steel infiltration layer does not easily blow off. However, simply lowering the strength by changing the molding pressure and the particle size composition of the conventional material lowers the durability, so it is important to balance with the durability.
【００１７】そこで、ガス吐出量が多い使用条件におい
て通気性耐火物の圧縮強度と熱間強度を低下することに
着目して、耐用性とのバランスを観察しながらテストを
繰り返し、使用結果との相関を調査した結果、アルミナ
質原料６５〜９０重量％及びムライト質原料３〜２５重
量％を使用し、且つ配合全体でＳｉＯ2の含有量が３〜
１０重量％で、焼成した後の圧縮強度が１〜２０ＭＰ
ａ、１４００℃での熱間曲げ強度が０．２〜２ＭＰａ、
通気率が２〜５ＣＧＳである通気性耐火物を使用すると
ほとんどガス吐出不良が発生しないことがわかった。Therefore, focusing on the fact that the compressive strength and the hot strength of the breathable refractory decrease under the use conditions where the gas discharge amount is large, the test is repeated while observing the balance between the durability and the use result. results of the examination of correlation, an alumina raw material 65 to 90% by weight and 3 to 25 wt% mullite feedstock, and the content of SiO 2 is 3 in total formulation
10% by weight, the compressive strength after firing is 1-20MP
a, the hot bending strength at 1400 ° C. is 0.2 to 2 MPa,
It has been found that when a gas-permeable refractory having a gas permeability of 2 to 5 CGS is used, gas discharge failure hardly occurs.
【００１８】また、粗粒部を粒子径が０．１〜１ｍｍの
アルミナ質原料とムライト質原料とから形成し、微粉部
に粘土と酸化クロムを５〜１５重量％使用することでよ
りガス吐出不良の改善効果が高いことがわかった。本発
明で言う粗粒部とは０．１ｍｍ以上の粒径を有する原料
を言い、微粉部とは０．１ｍｍ未満の原料を言う。The coarse particles are formed from an alumina raw material having a particle diameter of 0.1 to 1 mm and a mullite raw material, and 5 to 15% by weight of clay and chromium oxide are used in the fine powder to discharge more gas. It was found that the effect of improving the defect was high. In the present invention, the coarse particle portion refers to a raw material having a particle size of 0.1 mm or more, and the fine powder portion refers to a raw material having a particle size of less than 0.1 mm.
【００１９】低強度な材料にすると一番問題となるのは
耐用性の低下である。本発明のポーラスプラグは、耐用
回数は従来のものよりある程度少なくなるが、安全に使
用できる耐用性を備えておく必要から、耐食性の高いア
ルミナ質原料を主体に使用した。When a low-strength material is used, the greatest problem is a decrease in durability. The porous plug of the present invention has a somewhat less durable number of times than the conventional one, but is mainly made of a highly corrosion-resistant alumina-based material because it needs to have a durable life for safe use.
【００２０】本発明で使用するアルミナ質原料とは、Ａ
ｌ2Ｏ3含有率が９５％以上の原料であり、電融アルミ
ナ、焼結アルミナ等の一般に市販されている原料が使用
できる。使用量は６５〜９０重量％が好ましく、６５重
量％未満では耐食性が低下し、９０重量％を超えると粗
粒部が多すぎて微粉部が不足し低強度になってしまう。
粒度は粗粒部として０．１〜１ｍｍの範囲で使用すると
効果的であり、１ｍｍを超えると材料がぼろついて取り
扱い強度が低下し、０．１ｍｍ未満は組織中に良好な気
孔が形成されにくく低通気率になる。The alumina raw material used in the present invention is A
It is a raw material having a l 2 O 3 content of 95% or more, and generally available raw materials such as fused alumina and sintered alumina can be used. The use amount is preferably 65 to 90% by weight, and if it is less than 65% by weight, the corrosion resistance is reduced, and if it exceeds 90% by weight, the coarse particles are too large, the fines are insufficient, and the strength becomes low.
The grain size is effective when used as a coarse grain part in the range of 0.1 to 1 mm. When the grain size exceeds 1 mm, the material is ragged and the handling strength is reduced. When the grain size is less than 0.1 mm, good pores are not easily formed in the structure. Low air permeability.
【００２１】ムライト質原料としては、電融ムライト、
焼結ムライト等の市販品が使用できる。使用量は３〜２
５重量％が良く、３重量％未満では耐スポーリング性が
不足し、２５重量％を超えるとＳｉＯ2が多くなり耐食
性が低下する。粒度は１〜０．１ｍｍの範囲の使用が効
果的である。１ｍｍを超えると耐食性が低下し、０．１
ｍｍ未満では耐スポーリング性向上の効果が少ない。As the mullite material, electrofused mullite,
Commercial products such as sintered mullite can be used. 3 to 2 used
If the content is less than 3% by weight, the spalling resistance is insufficient. If the content is more than 25% by weight, the amount of SiO 2 is increased and the corrosion resistance is reduced. The use of a particle size in the range of 1 to 0.1 mm is effective. If it exceeds 1 mm, the corrosion resistance decreases, and 0.1
If it is less than mm, the effect of improving the spalling resistance is small.
【００２２】微粉部としてＡｌ2Ｏ3及びまたはＳｉＯ2
含有原料と酸化クロムが使用できるが、強度の面からは
粘土と酸化クロムを使用するとより効果的である。その
配合量は５〜１５重量％が好ましい。５重量％未満では
マトリクスとしての量が不足し低強度になり、１５重量
％を超えると微粉が多くなりすぎて通気率が低下する。Al 2 O 3 and / or SiO 2 as fine powder
Raw materials and chromium oxide can be used, but from the viewpoint of strength, it is more effective to use clay and chromium oxide. The compounding amount is preferably 5 to 15% by weight. If it is less than 5% by weight, the amount of the matrix will be insufficient and the strength will be low, and if it exceeds 15% by weight, the fine powder will be too large and the air permeability will be reduced.
【００２３】また、溶鋼の浸入を抑制するために、Ｓｉ
Ｏ2を３〜１０重量％含有する。ＳｉＯ2源としてはＳｉ
Ｏ2を含有する一般的な耐火原料を使用することがで
き、例えば、珪石、溶融シリカ、シリカフラワー、粘
土、ムライト及び／またはジルコニアムライト等を使用
する。ＳｉＯ2含有量が３重量％未満では溶鋼の浸入防
止が不十分で、１０重量％超えると耐食性が低下する。In order to suppress infiltration of molten steel, Si
O 2 and contains 3 to 10 wt%. Si as the SiO 2 source
General refractory raw materials containing O 2 can be used, for example, silica, fused silica, silica flour, clay, mullite, and / or zirconia mullite. If the SiO 2 content is less than 3% by weight, penetration of molten steel is insufficiently prevented, and if it exceeds 10% by weight, corrosion resistance is reduced.
【００２４】本発明の通気性耐火物は、このような配合
原料を使用して通常の方法で製造することができるが、
強度を低くするためには通常より成形圧力を下げること
で、所定の特性を有する通気性耐火物を得ることができ
る。また、焼成温度を通常より下げても圧縮強度を低下
することができる。The breathable refractory of the present invention can be produced by a usual method using such a blended raw material.
In order to lower the strength, the molding pressure is lower than usual, so that a breathable refractory having predetermined characteristics can be obtained. In addition, the compression strength can be reduced even if the firing temperature is lower than usual.
【００２５】焼成後に得られる通気性耐火物の物理的性
質は、ＪＩＳ Ｒ ２２０６による圧縮強度が１〜２０
ＭＰａであり、ＪＩＳ Ｒ ２６５６による１４００℃
での熱間曲げ強度が０．２〜２ＭＰａであり、ＪＩＳ
Ｒ ２１１５による通気率が２〜５ＣＧＳである。圧縮
強度が２０ＭＰａを超える場合、あるいは熱間曲げ強度
が２ＭＰａを超える場合には、ガス吐出不良が発生しや
すくなる。また、圧縮強度が１ＭＰａ未満の場合あるい
は熱間曲げ強度が０．２ＭＰａ未満の場合には耐用性に
問題が出てくる。また、通気率が２ＣＧＳ未満ではガス
吐出不良が発生しやすくなり、５ＣＧＳを超えると気孔
率が高くなりすぎて逆に溶鋼の浸入が深くなりバブリン
グ信頼性が低下する。The physical properties of the breathable refractory obtained after firing are as follows: the compressive strength according to JIS R 2206 is 1-20.
MPa, 1400 ° C according to JIS R 2656
Bending strength is 0.2 to 2 MPa in JIS
The air permeability by R 2115 is 2 to 5 CGS. When the compressive strength exceeds 20 MPa or when the hot bending strength exceeds 2 MPa, defective gas discharge is likely to occur. When the compressive strength is less than 1 MPa or when the hot bending strength is less than 0.2 MPa, there is a problem in durability. If the air permeability is less than 2 CGS, poor gas discharge is likely to occur. If the air permeability exceeds 5 CGS, the porosity becomes too high, and conversely, the infiltration of the molten steel becomes deep, and the bubbling reliability decreases.
【００２６】[0026]
【発明の実施の形態】表１に示す配合組成物に、水とバ
インダーを添加し混練後、プレスで成形し、乾燥後１６
００℃で焼成することで通気性耐火物を得た。溶鋼浸潤
深さは２０×２０×２００ｍｍの試験片を１６００℃の
溶鋼中に３分間浸漬後カットして溶鋼の浸潤厚みを測定
した。回転浸食試験は、１７００℃で酸化鉄を用いて行
い、溶損寸法で評価した。また耐スポーリング性を評価
するために、５０×５０×５０ｍｍの試験片を１０００
℃の炉に投入し３分キープ後取り出す操作を５回繰り返
して損傷状態を観察した。これらの結果を表１に示す。BEST MODE FOR CARRYING OUT THE INVENTION Water and a binder are added to the composition shown in Table 1, kneaded, molded by a press, dried and dried.
By baking at 00 ° C, a breathable refractory was obtained. The infiltration depth of the molten steel was determined by immersing a test piece of 20 × 20 × 200 mm in molten steel at 1600 ° C. for 3 minutes and then cutting the same to measure the infiltration thickness of the molten steel. The rotational erosion test was performed at 1700 ° C. using iron oxide, and evaluated by the erosion size. In order to evaluate the spalling resistance, a test piece of 50 × 50 × 50 mm was used for 1000 times.
The operation of throwing into a furnace at a temperature of 3 ° C., keeping for 3 minutes, and taking out was repeated 5 times to observe the damage state. Table 1 shows the results.
【００２７】[0027]
【表１】 実施例１は、焼結アルミナ７０重量％、電融ムライト２
２重量％、粘土５重量％及び酸化クロム３重量％からな
る配合物であり、溶鋼浸潤深さ、回転浸食テスト及びス
ポーリングテストの結果は良好であった。実施例２〜４
は、それぞれの組成を本発明の規定範囲内で変更したも
のである。何れも、メタル浸潤層は薄く、耐食性も良好
であった。[Table 1] In Example 1, 70% by weight of sintered alumina, fused mullite 2
The composition was composed of 2% by weight, 5% by weight of clay, and 3% by weight of chromium oxide. Examples 2 to 4
In the above, each composition was changed within the range specified in the present invention. In each case, the metal infiltration layer was thin and had good corrosion resistance.
【００２８】表１に示す比較例１は、アルミナ質原料が
６０重量％と少ないため、回転浸食テストでの溶損が大
きく耐食性が低い。比較例２はアルミナ質原料が多いた
めＳｉＯ2分が不足し、低強度となった。比較例３はム
ライト質原料が少ないため耐スポーリング性が劣る。比
較例４は、ムライト質原料が多すぎて耐食性が低下して
いる。比較例５はＳｉＯ2量が少ないためメタル浸潤層
が大きくなった。In Comparative Example 1 shown in Table 1, since the amount of the alumina raw material was as small as 60% by weight, the erosion was large in the rotary erosion test and the corrosion resistance was low. In Comparative Example 2, the content of SiO 2 was insufficient due to the large amount of the alumina raw material, and the strength was low. Comparative Example 3 is poor in spalling resistance due to a small amount of mullite raw material. In Comparative Example 4, the mullite raw material was too large and the corrosion resistance was reduced. In Comparative Example 5, since the amount of SiO 2 was small, the metal infiltration layer was large.
【００２９】表２は、使用原料が本発明の範囲内のもの
で、成形圧力を変えることで強度及び通気率を変化させ
た実施例を比較例とともに示す。評価は得られた通気性
耐火物でポーラスプラグを製作し、実際の取鍋でそれぞ
れ５回使用し、使用後の解析を行ったものである。Table 2 shows examples in which the raw materials used are within the scope of the present invention and the strength and the air permeability were changed by changing the molding pressure, together with comparative examples. In the evaluation, a porous plug was manufactured from the obtained breathable refractory, and the plug was used five times with an actual ladle and analyzed after use.
【００３０】バブリング信頼性は、３回使用した結果、
ガス吐出不良の有無と必要な流量が得られたかどうかで
評価した。問題なし−○、流量が不足−△、ガス吐出不
良−×とした。酸素洗浄性は、酸素洗浄時に必要な流量
が得られるまでの時間で評価し、２分以内−○、２〜５
分−△、５分以上−×とした。メタル浸潤深さは、使用
後のポーラスプラグの断面を観察した。The bubbling reliability was determined by using three times.
Evaluation was made based on the presence or absence of gas discharge failure and whether the required flow rate was obtained. No problem--, insufficient flow rate--, poor gas discharge-- Oxygen detergency is evaluated by the time until the required flow rate is obtained during oxygen detergency, and within 2 minutes-○, 2 to 5
Min- △, 5 minutes or more—X. The metal infiltration depth was determined by observing the cross section of the porous plug after use.
【００３１】[0031]
【表２】 表２において、実施例５〜８は、圧縮強度、熱間曲げ強
度及び通気率が発明の範囲内であり、実炉で良好に使用
されることがわかった。[Table 2] In Table 2, in Examples 5 to 8, the compressive strength, the hot bending strength and the air permeability were within the range of the invention, and it was found that they were favorably used in an actual furnace.
【００３２】比較例６は、圧縮強度と熱間曲げ強度が本
発明の規定範囲外でありバブリング信頼性に劣る。比較
例７と比較例８は通気率が本発明の規定範囲外であり、
バブリング信頼性に劣る。比較例９と１０は通気率を高
くするために従来の高強度タイプを低圧で成形したもの
であり、溶鋼浸潤深さが大きくバブリング信頼性に劣る
ことがわかる。In Comparative Example 6, the compressive strength and the hot bending strength were out of the ranges specified in the present invention, and the bubbling reliability was poor. In Comparative Examples 7 and 8, the air permeability was out of the specified range of the present invention,
Poor bubbling reliability. In Comparative Examples 9 and 10, the conventional high-strength type was molded at low pressure in order to increase the air permeability, and it can be seen that the molten steel infiltration depth was large and the bubbling reliability was poor.
【００３３】[0033]
【発明の効果】本発明のポーラスプラグは、耐食性に優
れ、且つ溶鋼浸入を抑制でき、通気量が多い条件で使用
しても操業が安定し、ガス吐出不良による操業の中断ス
トが低減する。The porous plug of the present invention is excellent in corrosion resistance, can suppress the infiltration of molten steel, stabilizes the operation even when used under the condition of a large amount of ventilation, and reduces the interruption of operation due to poor gas discharge.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 山本 正樹 福岡県北九州市八幡西区東浜町１番１号 黒崎窯業株式会社内 (72)発明者 続木 哲生 福岡県北九州市八幡西区東浜町１番１号 黒崎窯業株式会社内 Ｆターム(参考） 4G030 AA22 AA36 AA37 BA20 BA25 BA27 CA04 CA09 GA09 GA11 HA04 HA05 4K013 BA14 CA23 4K055 MA06 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaki Yamamoto 1-1, Higashihama-cho, Yawatanishi-ku, Kitakyushu-shi, Fukuoka Inside Kurosaki Ceramics Co., Ltd. F term in Kurosaki Ceramics Co., Ltd. (reference) 4G030 AA22 AA36 AA37 BA20 BA25 BA27 CA04 CA09 GA09 GA11 HA04 HA05 4K013 BA14 CA23 4K055 MA06
Claims (2)
イト質原料３〜２５重量％を含有し、全体のＳｉＯ2の
含有量が３〜１０重量％である配合物からなり、 焼成後の圧縮強度が１〜２０ＭＰａであり、 １４００℃での熱間曲げ強度が０．２〜２ＭＰａであ
り、 且つ、 通気率が２〜５ＣＧＳである通気性耐火物を使用したポ
ーラスプラグ。1. A composition containing 65 to 90% by weight of an alumina raw material and 3 to 25% by weight of a mullite raw material and having a total SiO 2 content of 3 to 10% by weight, and compression after firing. A porous plug using a breathable refractory having a strength of 1 to 20 MPa, a hot bending strength at 1400 ° C. of 0.2 to 2 MPa, and a permeability of 2 to 5 CGS.
径が１〜０．１ｍｍの粗粒部として含有されており、さ
らに、粘土と酸化クロムが微粉部として５〜１５重量％
含有されている請求項１に記載の通気性耐火物を使用し
たポーラスプラグ。2. An alumina-based material and a mullite-based material are contained as coarse particles having a particle size of 1 to 0.1 mm, and clay and chromium oxide are 5 to 15% by weight as fine powder.
A porous plug using the breathable refractory according to claim 1 contained therein.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23196799A JP4231164B2 (en) | 1999-08-18 | 1999-08-18 | Porous plug |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23196799A JP4231164B2 (en) | 1999-08-18 | 1999-08-18 | Porous plug |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2001059114A true JP2001059114A (en) | 2001-03-06 |
| JP4231164B2 JP4231164B2 (en) | 2009-02-25 |
Family
ID=16931867
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23196799A Expired - Fee Related JP4231164B2 (en) | 1999-08-18 | 1999-08-18 | Porous plug |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4231164B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115572156A (en) * | 2022-09-29 | 2023-01-06 | 浙江自立高温科技股份有限公司 | Aluminum-silicon-chromium breathable element without molten steel infiltration and preparation method thereof |
-
1999
- 1999-08-18 JP JP23196799A patent/JP4231164B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115572156A (en) * | 2022-09-29 | 2023-01-06 | 浙江自立高温科技股份有限公司 | Aluminum-silicon-chromium breathable element without molten steel infiltration and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4231164B2 (en) | 2009-02-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2103580B1 (en) | Durable sleeve bricks | |
| JP5774135B2 (en) | Sintered materials based on doped chromium oxide | |
| JPS6096567A (en) | Manufacture of sliding nozzle plate | |
| JPH09202667A (en) | Castable refractory for slide gate | |
| JPH082975A (en) | Refractory for casting application | |
| JP4231164B2 (en) | Porous plug | |
| JP3128515B2 (en) | Nozzle for continuous casting of steel | |
| JP4231163B2 (en) | Breathable refractory | |
| JP3015305B2 (en) | Nozzle for continuous casting of steel | |
| US6637629B2 (en) | Immersion nozzle | |
| JP2009242122A (en) | Brick for blast furnace hearth and blast furnace hearth lined with the same | |
| JP4589151B2 (en) | Nozzle for continuous casting and continuous casting method | |
| JP4203157B2 (en) | Magnesia refractory | |
| KR930009349B1 (en) | Refractory brick of mgo-c matrix | |
| JP2975849B2 (en) | Refractories for steelmaking | |
| JP2001030047A (en) | Immersion nozzle having sliding surface | |
| JPH08208313A (en) | Platelike refractory for sliding nozzle | |
| JP2002029858A (en) | Castable for lining tundish | |
| JP2795805B2 (en) | Ladle brick | |
| JP3177200B2 (en) | Method for producing low-permeability magnesia-chromium refractory | |
| JPH08104567A (en) | Zirconia refractory | |
| JP3536886B2 (en) | Method for producing porous refractory for gas-blown porous plug | |
| JP2604047B2 (en) | Porous high zirconia cast refractory and method for producing the same | |
| JP2001080969A (en) | Nonlithic refractory raw material and monolithic refractries | |
| JP2001153321A (en) | Monolithic refractory for slip casting construction of waste melting furnace and waste melting furnace using it |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20060810 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20080619 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080725 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080924 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20081107 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20081205 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111212 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20141212 Year of fee payment: 6 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |