JP2001059113A - Gas permeable refractory - Google Patents

Gas permeable refractory

Info

Publication number
JP2001059113A
JP2001059113A JP11231964A JP23196499A JP2001059113A JP 2001059113 A JP2001059113 A JP 2001059113A JP 11231964 A JP11231964 A JP 11231964A JP 23196499 A JP23196499 A JP 23196499A JP 2001059113 A JP2001059113 A JP 2001059113A
Authority
JP
Japan
Prior art keywords
raw material
molten steel
gas
gas permeable
bubbling
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
Application number
JP11231964A
Other languages
Japanese (ja)
Other versions
JP4231163B2 (en
Inventor
Tatsuya Ouchi
龍哉 大内
Shuichi Hara
周一 原
Masaki Yamamoto
正樹 山本
Tetsuo Tsuzuki
哲生 続木
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Krosaki Harima Corp
Original Assignee
Krosaki Harima Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Krosaki Harima Corp filed Critical Krosaki Harima Corp
Priority to JP23196499A priority Critical patent/JP4231163B2/en
Publication of JP2001059113A publication Critical patent/JP2001059113A/en
Application granted granted Critical
Publication of JP4231163B2 publication Critical patent/JP4231163B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Landscapes

  • Porous Artificial Stone Or Porous Ceramic Products (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Furnace Charging Or Discharging (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a gas permeable refractory for porous plugs, with which sufficient reliability of bubbling can be maintained, even in the case of treating molten steel having low viscosity, such as molten special steel. SOLUTION: Alumina spherical raw material having 0.1-0.5 mm grain diameter in a content of 60-90 wt.% and mullite quality raw material having 0.1-0.5 mm grain diameter in a content of 10-40 wt.%, are contained as a coarse grain raw material, and as the whole blended material, the content of raw material grains having >0.5 mm, is regulated to <=10 wt.%. The obtd. gas permeable refractory has 0.5-6 MPa hot bending strength at 1400 deg.C and 0.5-2.0 CGS permeability. In the case of using the gas permeable refractory, the reliability of the bubbling is improved and the interruption of the operation caused by defective spouting of the gas is reduced and the quality of the special steel is stabilized and the manufacturing cost is reduced.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、溶鋼中へガスを吹
き込むことにより、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取鍋等の底に取り付けられるポ
ーラスプラグに使用する通気性耐火物に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of blowing a gas into molten steel to make the temperature of the molten steel uniform with the stirring of the molten steel.
The present invention relates to a breathable refractory used for a porous plug attached to the bottom of a ladle or the like for homogenizing molten steel components, improving a secondary refining effect, and floating and removing nonmetallic inclusions.

【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5〜30回である。このポーラスプラ
グで最も重要な要求特性は、バブリングにおける信頼性
である。バブリング信頼性とは、必要な時に溶鋼中へ必
ずガスを吐出することができることを意味する。このバ
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、製造工程がここで中断してしまい、
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 5 to 30 times. The most important required characteristic of the porous plug is reliability in bubbling. Bubbling reliability means that gas can always be discharged into molten steel when needed. If the bubbling reliability is low and the gas cannot be discharged at the time of emergency, the molten steel component and the molten steel temperature cannot be made uniform, so the manufacturing process is interrupted here,
Molten steel must be returned to the converter or electric furnace.

【0003】一般にポーラスプラグは取鍋の底に取り付
けられており、多くの場合には先ず転炉や電気炉から溶
鋼を受鋼する時に溶鋼の攪拌を目的にガスを吐出する。
その後、ガス吹きを中断して鍋を移動し、例えば、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分間は、普通、ガスを吐出しない。
[0003] Generally, a porous plug is attached to the bottom of a ladle, and in many cases, first, when molten steel is received from a converter or an electric furnace, gas is discharged for the purpose of stirring the molten steel.
Thereafter, the gas blowing is interrupted and the pot is moved, and for example, gas is discharged again during ladle refining. Then, for about 60 minutes during casting after refining, gas is not normally discharged.

【0004】このようなポーラスプラグの使用において
問題となるのは、ガスの吐出を中断することである。こ
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
が浸入凝固して、溶鋼浸潤層を形成し、再びガスを吹い
てもガスが吐出しにくくなってしまい、中断後必要なガ
スを吐出するためには、ポーラスプラグ表面の溶鋼浸潤
層を相当なガス圧で吹き飛ばす必要がある。
A problem with the use of such a porous plug is that the gas discharge is interrupted. During this interruption, 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 the gas even if the gas is blown again, and discharge the necessary gas after the interruption. For this purpose, it is necessary to blow off the molten steel infiltration layer on the surface of the porous plug with a considerable gas pressure.

【0005】また、鋳造後取鍋が空になると、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ど
うかを測定して通気性能を確認する作業を行う。この
時、ガス圧でポーラスプラグの溶鋼浸潤層が吹き飛ぶ
と、新鮮な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。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もので、
酸素と溶融した酸化鉄によりポーラスプラグの表面の溶
鋼浸潤層が溶け、新鮮な表面を露出させることができ
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、洗浄不良によって
次の使用時にガス吐出不良になることもある。
[0005] When the ladle is empty after casting, gas is supplied to the porous plug to measure whether a predetermined flow rate is secured and to check the ventilation performance. At this time, if the molten steel infiltration layer of the porous plug blows off due to the gas pressure, the surface of the fresh refractory is exposed, so that a satisfactory flow rate can be secured. However, when the flow rate is insufficient, the surface needs to be cleaned with oxygen. This work is to blow oxygen from an iron pipe toward the tip of the porous plug with gas pressure applied to the porous plug,
The molten steel infiltration layer on the surface of the porous plug is melted by the oxygen and the molten iron oxide, so that a fresh surface can be exposed. This operation is a high-temperature operation, and it is very difficult to reliably clean the bottom of the pot because it is difficult to see the bottom of the pot.

【0006】このポーラスプラグのガス吐出再開に際し
ての溶鋼浸潤層の影響を少なくするための試みが従来か
ら多く提案されている。
Many attempts have been made to reduce the influence of the molten steel infiltration layer when resuming gas discharge from 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0.3〜1mm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侵入を少な
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 a gas discharge defect, a pore diameter of 0.3 to 1 mm of alumina spherical raw material is used. It is described that the distribution width of steel is narrowed to reduce the intrusion of molten steel.

【0008】また、特公平7−74091号公報には、
溶鋼浸潤層形成部分にジルコニアムライト原料を使用す
ることで、ジルコニアムライトとメタル及びスラグが反
応し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 by using a zirconia mullite raw material in a portion where a molten steel infiltration layer is formed, zirconia mullite reacts with metal and slag to improve viscosity and reduce infiltration of molten steel.

【0009】上記の対策によって、通常の場合には、確
かに、ある程度の効果が見られたが、特殊鋼のように溶
鋼の粘性が低い場合には、溶鋼浸潤層の形成を低減する
効果は少なく、普通鋼の場合と比較してガスを吹き込も
うとしてもガスが吐出するまで時間を要したり、ガスが
出ても流量が不足する場合があった。さらには、取鍋が
空になって酸素洗浄する時にも、また、取鍋の滞留時間
が長い場合にも、さほどの効果は期待できなかった。
Although the above countermeasures certainly have a certain effect in the normal case, when the viscosity of the molten steel is low, as in the case of special steel, the effect of reducing the formation of the molten steel infiltration layer is not significant. In some cases, as compared with the case of ordinary steel, even if gas is blown, it takes time until the gas is discharged, and even if the gas comes out, the flow rate may be insufficient. Further, when the ladle is emptied and oxygen washing is performed, or when the ladle has a long residence time, no significant effect can be expected.

【0010】[0010]

【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、特殊鋼のように粘性が低い溶鋼を処理する
場合にも、十分なバブリング信頼性を維持できるポーラ
スプラグのための通気性耐火物を提供することにある。
SUMMARY OF THE INVENTION The problem to be solved by the present invention is to provide a porous plug having sufficient air-permeability even when treating low-viscosity molten steel such as specialty steel. It is to provide refractories.

【0011】[0011]

【課題を解決するための手段】特殊鋼の場合に溶鋼浸潤
層が吹き飛ばしにくくなり普通鋼の場合と比べてガス吐
出不良が発生し易い原因は、特殊鋼の場合には溶鋼の粘
性が低いことが多いため、普通鋼よりもポーラスプラグ
使用中に通気性耐火物中により深く溶鋼が侵入して溶鋼
浸潤層が厚くなることによると推定される。
[Means for Solving the Problems] The reason why the molten steel infiltration layer is less likely to be blown off in the case of special steel and gas discharge failure is more likely to occur than in the case of ordinary steel is that the viscosity of the molten steel is low in the case of special steel. This is presumed to be due to the fact that the molten steel penetrates deeper into the gas-permeable refractory when the porous plug is used than the ordinary steel, and the molten steel infiltration layer becomes thicker.

【0012】そこで、一旦、使用した後のポーラスプラ
グのガス吐出不良は、溶鋼を侵入しにくくして溶鋼浸潤
層を形成し難くし、且つ、ガス吐出による溶鋼浸潤層を
吹き飛ばし易くすることで改善できることに着目した。
Therefore, poor gas discharge of the porous plug once used is improved by making it difficult for molten steel to penetrate and to form a molten steel infiltration layer, and making it easy to blow out the molten steel infiltration layer by gas discharge. We focused on what we could do.

【0013】先ず、溶鋼を侵入しにくくするためには、
ポーラスプラグの気孔径を小さくすることが考えられ
る。そして、気孔径を小さくするためには、使用する原
料の粒度をさらに小さくする必要がある。しかしなが
ら、使用する原料の粒度を小さくして通気率を小さくす
ると、他方において、精錬時に必要な吐出ガス流量を確
保できない問題がある。従来、ポーラスプラグに使用す
る原料の粒度は、例えば、特開平10−251738号
公報には粒径0.3〜1mmのアルミナ原料を使用する
ことが示されているが、通常は1mm以下の原料を主体
に使用している。ところが、本発明者等のこれまでの経
験からは、この粒度構成では溶鋼浸潤層の厚みを小さく
するのは難しいことが分かっている。
First, in order to make it difficult for molten steel to enter,
It is conceivable to reduce the pore diameter of the porous plug. In order to reduce the pore diameter, it is necessary to further reduce the particle size of the raw material used. However, reducing the particle size of the raw material to be used and reducing the air permeability, on the other hand, has a problem in that the flow rate of the discharge gas required during refining cannot be secured. Conventionally, as for the particle size of the raw material used for the porous plug, for example, Japanese Patent Application Laid-Open No. H10-251538 discloses that an alumina raw material having a particle size of 0.3 to 1 mm is used. Is mainly used. However, the experience of the present inventors shows that it is difficult to reduce the thickness of the molten steel infiltration layer with this grain size configuration.

【0014】次に、溶鋼浸潤層をガス圧で吹き飛び易く
するための方策について考えると、溶鋼浸潤層と未浸潤
部との境界付近における膨張率の差等から形成されてい
る亀裂を利用して、ガス圧を加え、この亀裂を基点に先
端部を吹き飛ばす着想を得た。この着想の実現のために
は、この部分の強度を下げて吹き飛び易くすることを考
えた。
Next, considering a method for making the molten steel infiltrated layer easily blow off by gas pressure, a crack formed by a difference in expansion coefficient near the boundary between the molten steel infiltrated layer and the uninfiltrated portion is utilized. , Gas pressure was applied and the tip was blown off from the crack as a base point. To realize this idea, we considered reducing the strength of this part to make it easier to blow off.

【0015】本願発明は、この強度の指標として通気性
耐火物熱間での曲げ強度に着目して完成した。従来のポ
ーラスプラグに使用される通気性耐火物の熱間強度は、
例えば特開平10−182259号公報においては、1
400℃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、また、単に
熱間強度を下げるだけでは耐用性が低下するので、耐用
性とのバランスをとることが重要である。
The present invention has been completed by focusing on the bending strength between heat of a breathable refractory as an index of the strength. The hot strength of breathable refractories used for conventional porous plugs is
For example, in JP-A-10-182259, 1
It is said that 12 to 14 MPa at 400 ° C. is good. However, this strength makes it difficult for the molten steel infiltration layer to blow off, and simply lowering the hot strength lowers the durability, so balance with the durability. is important.

【0016】すなわち、本発明は、粒径0.1〜0.5
mmのアルミナ球状原料を60〜90重量%と、粒径
0.1〜0.5mmのムライト質原料を10〜40重量
%を粗粒原料として使用し、配合物全体で0.5mmを
超える原料粒子が10重量%以下とした通気性耐火物を
得て、耐用性と熱間強度とのバランスがとれ、ガス吐出
に際して溶鋼浸潤層が吹き飛び易く、ガス吐出の信頼性
に優れたポーラスプラグとすることができた。
That is, according to the present invention, the particle size is 0.1 to 0.5.
mm-alumina spherical raw material of 60 to 90% by weight and mullite raw material of 0.1 to 0.5 mm in particle size of 10 to 40% by weight as coarse raw material, and a raw material exceeding 0.5 mm in the whole composition A porous plug with a particle of 10% by weight or less is obtained, and a balance between durability and hot strength is obtained, the molten steel infiltration layer easily blows off when discharging gas, and the gas plug has excellent gas discharging reliability. I was able to.

【0017】本発明において、粗粒とは0.1mm以上
の原料粒子を意味し、主として気孔を形成するための骨
格となる。これに対して微粉部は、0.1mm未満の原
料粒子のことで、粗粒どうしを接着するためのマトリク
ス部を構成する。
In the present invention, coarse particles mean raw material particles having a diameter of 0.1 mm or more, and mainly serve as a skeleton for forming pores. On the other hand, the fine powder portion refers to raw material particles having a size of less than 0.1 mm, and constitutes a matrix portion for bonding coarse particles.

【0018】本発明において粗粒として使用するアルミ
ナ原料は、一般に市販されている球状原料を使用する。
球状でない原料を使用すると、通気に寄与しない密閉気
孔が増加するので十分な強度が得られにくく、また気孔
径が大きくなり、且つ、ばらつきが生じ易い。粒径が
0.5mmを超えると気孔径が大きくなり溶鋼が侵入し
易くなり、0.1mm未満では気孔径が小さくなりすぎ
て低通気率となってしまう。その使用量が60重量%未
満では、良好な通気性のある気孔が形成されにくくな
り、90重量%を超えると微粉部が不足するため結合強
度が不足してしまう。また、Al23含有量が95重量
%以上のものであれば十分使用することができ、95重
量%以下ではスラグ等による溶損が大きくなり耐用性が
低下する。
As the alumina raw material used as coarse particles in the present invention, generally available spherical raw materials are used.
When a non-spherical raw material is used, the number of closed pores that do not contribute to ventilation increases, so that it is difficult to obtain sufficient strength, and the pore diameter is large and variation is likely to occur. If the particle size exceeds 0.5 mm, the pore diameter becomes large and molten steel easily penetrates. If the particle size is less than 0.1 mm, the pore diameter becomes too small, resulting in low air permeability. If the amount is less than 60% by weight, pores having good air permeability are difficult to be formed. If the amount is more than 90% by weight, the fine powder portion is insufficient and the bonding strength is insufficient. If the Al 2 O 3 content is 95% by weight or more, it can be used satisfactorily. If the Al 2 O 3 content is 95% by weight or less, erosion due to slag or the like becomes large and durability is reduced.

【0019】同じく粗粒部として使用するムライト質原
料は、一般に市販されている電融ムライトや合成ムライ
トが使用でき、粒径が0.1〜0.5mmの範囲のもの
を10〜40重量%使用する。粒径が0.5mmを超え
ると気孔径が大きくなり溶鋼が侵入し易くなり、0.1
mm未満では気孔径が小さくなりすぎて低通気率となっ
てしまう。ムライト質原料は耐スポーリング性を付与す
るためと溶鋼浸潤を少なくするために使用し、その使用
量が10重量%未満では、耐スポーリング性が不足し、
40重量%を超えるとSiO2が多くなり耐食性が低下
する。
As the mullite raw material also used as the coarse-grained portion, commercially available fused mullite or synthetic mullite can be used, and those having a particle size in the range of 0.1 to 0.5 mm are 10 to 40% by weight. use. If the particle size exceeds 0.5 mm, the pore diameter becomes large and molten steel easily penetrates,
If it is less than mm, the pore diameter becomes too small, resulting in a low air permeability. The mullite raw material is used for imparting spalling resistance and for reducing the infiltration of molten steel. If the amount is less than 10% by weight, the spalling resistance is insufficient.
If it exceeds 40% by weight, SiO 2 increases and the corrosion resistance decreases.

【0020】この他に、粗粒原料としては、これらに加
えて一般に通気性耐火物に使用する原料、例えばジルコ
ニア、ジルコニアムライト、マグネシア、スピネル等が
使用できる。
In addition, raw materials generally used for breathable refractories, such as zirconia, zirconia mullite, magnesia, and spinel, can be used as coarse-grained raw materials.

【0021】また、微粉部の原料としては、粒径0.1
mm未満の従来の通気性耐火物に使用されている原料を
使用することができる。中でも仮焼アルミナ、粘土及び
酸化クロムからなる微粉部を使用するとマトリクス部の
耐食性の面から効果的である。仮焼アルミナと酸化クロ
ムは耐食性を向上させ、粘土は結合力を高める効果があ
る。
The raw material of the fine powder portion has a particle size of 0.1
Raw materials used for conventional breathable refractories of less than mm can be used. Among them, the use of a fine powder portion composed of calcined alumina, clay and chromium oxide is effective in terms of the corrosion resistance of the matrix portion. Calcined alumina and chromium oxide improve the corrosion resistance, and clay has the effect of increasing the bonding strength.

【0022】原料配合物全体では、0.5mm以上の原
料は10重量%以下である必要がある。通気性耐火物の
溶鋼浸潤層を小さくするためには、0.5mm以上の原
料を使用しないほうが効果が大であるが、配合物全体の
10重量%以下であれば許容範囲内として悪影響なく使
用できる。この理由から、粒径が0.5mmを超えるア
ルミナ球状原料又は電融ムライト原料は使用可能である
が、配合全体の0.5mm以上の原料が10重量%以下
の範囲内で使用する。
In the entire raw material mixture, the raw material having a size of 0.5 mm or more needs to be 10% by weight or less. In order to reduce the molten steel infiltration layer of the breathable refractory, it is more effective not to use a raw material of 0.5 mm or more, but if it is 10% by weight or less of the whole composition, it is used within an allowable range without any adverse effect. it can. For this reason, an alumina spherical raw material or an electrofused mullite raw material having a particle size of more than 0.5 mm can be used, but the raw material having a size of 0.5 mm or more in the entire mixture is used within a range of 10% by weight or less.

【0023】上記の原料配合物を通常の成形、乾燥、焼
成を経ることで、1400℃での熱間曲げ強度が0.5
〜6MPで、通気率が0.5〜2.0CGSの通気性耐
火物を得ることができる。
By subjecting the above raw material mixture to normal molding, drying and firing, the hot bending strength at 1400 ° C. is 0.5.
At ~ 6MP, a breathable refractory having a permeability of 0.5 to 2.0 CGS can be obtained.

【0024】通常の通気性耐火物の熱間曲げ強度は、J
IS R 2656による測定方法の測定結果では、1
0MPa前後であるが、本発明の場合、0.5〜6MP
aと通常より熱間曲げ強度が低い範囲が良好である。こ
の理由は、本発明で特定する原料配合物から通気性耐火
物を製造する場合、この範囲内の時にバブリング信頼性
が高くなるからである。熱間強度が6MPaを超えると
使用時にポーラスプラグの表面の溶鋼浸潤層が吹き飛び
にくくなるためか、ガス吐出不良が発生し易くなり、熱
間強度が0.5MPa未満では耐用性が低下する。
The hot bending strength of ordinary breathable refractories is J
According to the measurement result of the measurement method according to IS R 2656, 1
Although it is around 0 MPa, in the case of the present invention, it is 0.5 to 6MPa.
a and the range where the hot bending strength is lower than usual are good. The reason for this is that when producing a breathable refractory from the raw material mixture specified in the present invention, bubbling reliability is increased when the content falls within this range. If the hot strength exceeds 6 MPa, the molten steel infiltration layer on the surface of the porous plug is less likely to be blown off during use, or gas discharge failure is likely to occur. If the hot strength is less than 0.5 MPa, the durability decreases.

【0025】また、本発明の通気性耐火物の通気率は、
JIS R 2115による通気率は、0.5〜2.0
CGSである。0.5CGS未満では精錬作業時の流量
が不足し、2.0CGSを超えると気孔径が大きくなる
ため溶鋼が侵入しガス吐出不良になる。
Further, the permeability of the breathable refractory of the present invention is as follows:
The air permeability according to JIS R 2115 is 0.5 to 2.0
CGS. If it is less than 0.5 CGS, the flow rate during the refining operation will be insufficient, and if it exceeds 2.0 CGS, the pore diameter will be large, so molten steel will penetrate, resulting in poor gas discharge.

【0026】[0026]

【発明の実施の形態】以下、具体的な実施例によって本
発明の実施の形態を説明する。
Embodiments of the present invention will be described below with reference to specific examples.

【0027】[0027]

【表1】 表1に示す配合物に、水とバインダーを添加し混練後、
プレスで成形し、乾燥後1650℃で焼成することで通
気性耐火物を得た。
[Table 1] After adding water and a binder to the composition shown in Table 1 and kneading,
It was molded by a press, dried and fired at 1650 ° C. to obtain a breathable refractory.

【0028】実施例1〜6は、アルミナ球状原料と電融
ムライトの粒度構成を特定範囲内で変更し、さらに、こ
れにジルコニアムライト、粘土、酸化クロム、仮焼アル
ミナを含有した例を示している。
Examples 1 to 6 show examples in which the particle size composition of the alumina spherical raw material and the electrofused mullite was changed within a specific range, and further contained zirconia mullite, clay, chromium oxide, and calcined alumina. I have.

【0029】比較例1〜3は、0.5mm以上の原料が
本発明の規定範囲外であり比較例4と比較例5は粗粒に
0.1〜1mmの範囲の原料を使用した例である。
In Comparative Examples 1 to 3, raw materials having a size of 0.5 mm or more are out of the specified range of the present invention, and Comparative Examples 4 and 5 are examples in which raw materials having a range of 0.1 to 1 mm are used for coarse particles. is there.

【0030】評価は得られたそれぞれの通気性耐火物か
らなるポーラスプラグを、実際の取鍋でそれぞれ3回使
用し、使用後の解析した結果によって行った。
The evaluation was carried out by using the obtained porous plug made of the breathable refractory three times in an actual ladle and analyzing the results after use.

【0031】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。溶鋼浸潤深さは、使用後
のポーラスプラグの断面を観察した。また使用後の損傷
寸法で耐食性を評価したものである。
The bubbling reliability was determined as a result of 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 infiltration depth of the molten steel was determined by observing the cross section of the porous plug after use. Further, the corrosion resistance was evaluated based on the damage size after use.

【0032】同表に示すように、何れの実施例も、バブ
リング信頼性、酸素洗浄性、メタル浸潤深さ、耐用回数
ともに良好であった。
As shown in the table, all of the examples exhibited good bubbling reliability, oxygen cleaning properties, metal infiltration depth, and useful life.

【0033】これに対して、比較例1は、実使用でバブ
リング信頼性と酸素洗浄性が不良であった。比較例2は
熱間曲げ強度が0.5MPaより低く、損傷寸法が大き
く耐用性に劣る結果となった。比較例3は、熱間曲げ強
度が7MPaと大きくかつ通気率が0.5CGSより小
さく、バブリング信頼性に劣る結果となった。比較例4
及び比較例5は粗粒に1〜0.1mmの範囲の原料を使
用した例であるが、気孔径が大きくかつ熱間強度が高い
ためバブリング信頼性が低く酸素洗浄に時間を要する結
果となった。
On the other hand, Comparative Example 1 was inferior in bubbling reliability and oxygen cleanability in actual use. In Comparative Example 2, the hot bending strength was lower than 0.5 MPa, the damage size was large, and the durability was poor. In Comparative Example 3, the hot bending strength was as large as 7 MPa and the air permeability was smaller than 0.5 CGS, resulting in poor bubbling reliability. Comparative Example 4
And Comparative Example 5 is an example in which the raw material in the range of 1 to 0.1 mm is used for the coarse particles. However, since the pore diameter is large and the hot strength is high, the bubbling reliability is low and the oxygen cleaning requires time. Was.

【0034】[0034]

【発明の効果】本発明の通気性耐火物を使用することに
よって、ポーラスプラグのバブリング信頼性は向上し、
ガス吐出不良による操業の中断が減少し、品質が安定す
るとともに製造コストは低減する。
By using the breathable refractory of the present invention, the bubbling reliability of the porous plug is improved.
Disruption of operation due to poor gas discharge is reduced, and quality is stabilized and manufacturing cost is reduced.

【0035】また、酸素洗浄時間を短くすることができ
るので、高熱下での作業負荷が軽減できる。
Further, since the oxygen cleaning time can be shortened, the work load under high heat can be reduced.

【0036】さらに、比較的溶鋼による浸潤層の形成が
少ない使用条件においては、酸素洗浄しなくてもバブリ
ング信頼性は良好となる。
Further, under the use condition in which the formation of the infiltration layer by the molten steel is relatively small, the bubbling reliability is improved without oxygen cleaning.

───────────────────────────────────────────────────── 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) 4G019 FA11 4K013 BA14 CA18 CA23 4K055 MA06  ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masaki Yamamoto 1-1-1, Higashihama-cho, Yawatanishi-ku, Kitakyushu-city, Fukuoka Prefecture (72) Inventor Tetsuo Suzuki 1-1-1, Higashihama-cho, Yawatanishi-ku, Kitakyushu-shi, Fukuoka F term in Kurosaki Ceramics Co., Ltd. (reference) 4G019 FA11 4K013 BA14 CA18 CA23 4K055 MA06

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 粒径0.1〜0.5mmのアルミナ球状
原料を60〜90重量%と粒径0.1〜0.5mmのム
ライト質原料を10〜40重量%を粗粒原料として含
み、配合物全体で0.5mmを超える原料粒子の含有量
が10重量%以下であることを特徴とする通気性耐火
物。
1. A coarse-grain raw material comprising 60 to 90% by weight of an alumina spherical raw material having a particle size of 0.1 to 0.5 mm and 10 to 40% by weight of a mullite raw material having a particle size of 0.1 to 0.5 mm. A breathable refractory, characterized in that the content of raw particles exceeding 0.5 mm in the whole composition is 10% by weight or less.
【請求項2】 1400℃での熱間曲げ強度が0.5〜
6MPa、通気率が0.5〜2.0CGSであることを
特徴とする請求項1に記載の通気性耐火物。
2. A hot bending strength at 1400 ° C. of 0.5 to
The breathable refractory according to claim 1, wherein the refractory has a pressure of 6 MPa and a permeability of 0.5 to 2.0 CGS.
JP23196499A 1999-08-18 1999-08-18 Breathable refractory Expired - Lifetime JP4231163B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP23196499A JP4231163B2 (en) 1999-08-18 1999-08-18 Breathable refractory

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP23196499A JP4231163B2 (en) 1999-08-18 1999-08-18 Breathable refractory

Publications (2)

Publication Number Publication Date
JP2001059113A true JP2001059113A (en) 2001-03-06
JP4231163B2 JP4231163B2 (en) 2009-02-25

Family

ID=16931820

Family Applications (1)

Application Number Title Priority Date Filing Date
JP23196499A Expired - Lifetime JP4231163B2 (en) 1999-08-18 1999-08-18 Breathable refractory

Country Status (1)

Country Link
JP (1) JP4231163B2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007099562A (en) * 2005-10-04 2007-04-19 Kurosaki Harima Corp Air permeable refractory and method of producing the same
US8186999B2 (en) 2003-12-10 2012-05-29 Nobel Biocare Services Ag System and arrangement for production and insertion of a dental bridge structure
JP2015038031A (en) * 2005-09-26 2015-02-26 サン−ゴバン セントレ デ レシェルシェ エト デチュード ユーロピーン Sintered refractory product exhibiting enhanced thermal shock resistance

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8186999B2 (en) 2003-12-10 2012-05-29 Nobel Biocare Services Ag System and arrangement for production and insertion of a dental bridge structure
JP2015038031A (en) * 2005-09-26 2015-02-26 サン−ゴバン セントレ デ レシェルシェ エト デチュード ユーロピーン Sintered refractory product exhibiting enhanced thermal shock resistance
JP2007099562A (en) * 2005-10-04 2007-04-19 Kurosaki Harima Corp Air permeable refractory and method of producing the same

Also Published As

Publication number Publication date
JP4231163B2 (en) 2009-02-25

Similar Documents

Publication Publication Date Title
JP5016609B2 (en) High durability sleeve brick
EP0006775B1 (en) Gas-permeable refractory elements
JP5166302B2 (en) Continuous casting nozzle
JP2001059113A (en) Gas permeable refractory
JPH082975A (en) Refractory for casting application
JP2012062232A (en) Air-permeability refractory and its manufacturing method
JP2009242122A (en) Brick for blast furnace hearth and blast furnace hearth lined with the same
US6637629B2 (en) Immersion nozzle
JP4231164B2 (en) Porous plug
JP4456443B2 (en) Pitch-containing difficult adhesion continuous casting nozzle
JP3803740B2 (en) Manufacturing method of refractories for gas blowing
JP4589151B2 (en) Nozzle for continuous casting and continuous casting method
JP4203157B2 (en) Magnesia refractory
JPH0952755A (en) Magnesia-chrome refractory
JP6855646B1 (en) Refractory for sliding nozzle plate and its manufacturing method
JP3774557B2 (en) Refractory for injecting inert gas into molten metal and method for producing the same
JP2007099562A (en) Air permeable refractory and method of producing the same
JP2002012478A (en) Slip casting material of hot-metal conduit including blast furnace conduit
JPH10158072A (en) Magnesia-carbon castable refractory and its applied body
JP2005187289A (en) Fireproofing material for spraying
JP3238592B2 (en) Irregular cast refractory moldings
JP2810111B2 (en) Gas injected refractories
JP2001030047A (en) Immersion nozzle having sliding surface
JP2004323260A (en) Nozzle material for continuous casting and nozzle for continuous casting
JPH08208313A (en) Platelike refractory for sliding nozzle

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

Ref document number: 4231163

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

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

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

EXPY Cancellation because of completion of term