JP3714697B2 - Blast furnace outlet - Google Patents
Blast furnace outlet Download PDFInfo
- Publication number
- JP3714697B2 JP3714697B2 JP05645795A JP5645795A JP3714697B2 JP 3714697 B2 JP3714697 B2 JP 3714697B2 JP 05645795 A JP05645795 A JP 05645795A JP 5645795 A JP5645795 A JP 5645795A JP 3714697 B2 JP3714697 B2 JP 3714697B2
- Authority
- JP
- Japan
- Prior art keywords
- blast furnace
- refractory
- resistance
- furnace outlet
- weight
- 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 - Fee Related
Links
Landscapes
- Ceramic Products (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
- Furnace Housings, Linings, Walls, And Ceilings (AREA)
Description
【0001】
【産業上の利用分野】
本発明は高炉において溶銑およびまたは溶滓を流出させるための高炉の出銑口に関するものである。
【0002】
【従来の技術】
高炉の出銑口は一般に珪酸塩耐火材およびまたは高アルミナ材に炭化珪素材およびまたは窒化珪素材や炭素質材が配合されたマッド材と称される練土状の不定形耐火物を閉塞機(マッドガン)を用いて圧入充填することにより閉塞される。そして出銑時には開口機により出銑口を閉塞しているマッド材中に鉄棒を打ち込むことにより穿孔開口して出銑を行なっている。
近年、高炉の操業は羽口から熱風と共に重油、ピッチや微粉炭等の燃料を共に炉内に吹き込むことにより、燃費の引き下げや出銑量の増加等高生産性となり、非出銑時間が短くなり、出銑のための出銑口の開閉作業が頻繁となり、高熱下での作業の度合が高まって来た。また従来のマッド材では出銑時に溶銑および溶滓による浸食や損耗が大きく、出銑口径の拡大のために安定した操業が出来ず、また溶銑と溶滓との混合度が高まり品質的にも悪影響をおよぼす結果となっている。尚現在の出銑所要時間は一般に約3〜4時間で1日当りほぼ5〜6回の程度の出銑回数となっている。又出銑口の開閉作業は高温且つ悪環境下での作業であるため、此の作業の増加は環境衛生上および操業の安全上問題が多いばかりではなく、安定した出銑が行えず、溶銑の湯道となる主樋、スキンマー部、溶銑樋およびスラグ樋等の使用条件が過酷となり、その損傷が激しいので前記の如く珪酸塩材およびまたは高アルミナ材を主材とし、これに炭素質材,炭化珪素材や窒化珪素材の少なくとも一者以上を配合した練土状の不定形耐火物,マッド材が使用されているが、いまだ上記諸問題を解決する迄には至っていない。またこれらの問題点を解決するために特開平2−205610号公報には出銑口に円筒形の耐火物を装着した出銑口を形成する方法(以下先行技術と云う)が開示されているが、出銑口を形成する円筒形の耐火物によって出銑時における出銑口の損傷拡大が抑制され、長時間の出銑が可能となり、出銑口の開閉回数の減少を図ることが出来るとしているが、これに用いられる円筒状の耐火物の使用条件より熱間での強度および粘性が高く高温下での耐摩耗性に秀でており、溶銑や溶滓に対する反応性が小さいことかつ熱応力に対する抵抗性が高く、割れにくい性質を具備することが必要とされるが、これらの要求を満足させ得る耐火物が得られず、この方法でも現在所期の目的を達成する迄に至ってないのが現状である。
【0003】
【発明が解決しようとする課題】
本発明はこの現状に鑑み、前述した諸問題を解決し得る円筒状耐火物として溶銑,溶滓に対する化学的反応性が小さく熱間強度、粘性が高くて高温下での耐摩耗性に秀ぐれかつ熱応力に対する抵抗性が高くて、割れにくい特性を具備して使用中の出銑口の拡大が小さく、長時間の安定した出銑を可能とし、出銑回数を減少することの出来る高炉出銑口用円筒形状の耐火物を提供することにある。
【0004】
【課題を解決するための手段】
本発明者等は前述した諸問題を解決すべく鋭意研究をかさねた結果、高炉出銑口の使用条件より
▲1▼熱間での強度および粘性が高く高温下での耐摩耗性が高いこと。
▲2▼溶銑および溶滓に対する反応性が小さく溶損が少ないこと。
▲3▼熱応力に対する抵抗性が高く割れにくいこと。
等々が求められることに着目し、前記3項に対する満足すべき耐火材料として炭化珪素質材およびAl2O390%以上を含有する高アルミナ質材やアルミナ質材による複合耐火物が最も適合する耐火材構成であることを種々基礎試験の結果見い出した。その耐火物の素材構成は炭化珪素質材20〜90重量%,アルミナ質材5〜50、ムライト質材5〜30重量%としてSiCとAl2O3およびSiO2を必須成分として含有し、このSiCとAl2O3およびSiO2の3者の合量が90%以上であり、かつ気孔率が15%以下であることを特徴とするものである。
【0005】
次に本発明の円筒形状の耐火物の限定した理由を示す。
▲1▼炭化珪素質材20〜90重量%については、
SiCは熱間強度および熱間耐摩耗性を高め且つ高熱伝導性材であるため溶損が少なくかつ有害な亀裂,割れの発生を抑制することが出来るが90重量%以上となると組織の結合力が弱くなり熱間耐摩耗性が劣化する。又20%以下となると組織の結合力が弱くなり、強度が低くかつ熱伝導率の低下を招き、耐損傷性,耐亀裂割れ性が劣化し耐用寿命が短くなるためである。
▲2▼アルミナ(Al2O3)質材5〜50重量%については
Al2O3は耐食性および強度を高めるが含有量が5重量%未満となると組織の結合力の向上結果が小さく、又50重量%を超えると耐熱スポーリング性が低くなり、割れが発生し易くなるためである。
▲3▼ムライト質材5〜30重量%については
ムライト質材料は耐火物自体の耐熱衝撃性を高め、かつ針状結晶質物であるため熱間温度を高めるものであるが、5重量%以内ではその効果が小さくかつ30重量%を超えると耐化学的溶損性がそこなわれるためである。
▲4▼SiCとAl2O3およびSiO2の合量が90%以下の含有量となると混入素材によっては異なるが一般に多成分系となり耐熱性、耐食性および熱間強度が低下し更に耐熱衝撃性の低下を招き、耐用寿命の低下をきたす等の欠点を生ずるためである。
▲5▼気孔率が15%以上となると組織緻密度が低くなるため、組織内への異物の浸透度が高くなり、耐食性が低くなると共に溝状亀裂の発生がし易くかつ耐熱間摩耗性が低くなることにより15%以下とする。
【0006】
【実施例】
次に本発明の円筒状の耐火物の実施例を示す。
実施例に用いる材料の化学成分値例を表1、円筒形状耐火物の粒度構成を表2に示す。
【0007】
【表1】
【0008】
【表2】
【0009】
【表3】
【0010】
本発明の実施例は表1に示した各種耐火材料を用い、表2に示す粒度構成として、SiO2系の無機質バインダー2重量%および水4.5重量%を添加、混練した後、この混練物を吸水性鋳型を振動させながらこの鋳型内に徐々に投入して充填し、保形できる程度に硬化した後、脱型、乾燥し、最高温度1550℃、総時間65時間で焼成して製作した結果を比較品とともに表3に示す。
【0011】
以上の結果から、これらのうちから本発明品1、2および比較品No2、No3を供試材として高炉の出銑口で実炉試験を行ったその結果を表4に示す。
【0012】
【表4】
【0013】
表3に示されるように炭化珪素質材とアルミナ質材を一定としムライト質材の添加量について耐熱スポーリング性を考慮し本発明品1、2および比較品としてムライト無添加品である比較品No2について試作品と同じ製造方法により内径φ50mm外径φ120mm長さ500mmの円筒形耐火物を成形し最高温度1550℃で焼成し、高炉出銑口用耐火物を製出する。この円筒形の出銑口用耐火物を2本継ぎセットして実使用を行う。また比較品No3は従来通りの不定形耐火物マッド材として出銑口部に閉塞機を用いて直接圧入施工を行い同様実用に供する。この使用実施条件は次の通りである。
1.高炉の炉容量 2828cm3
2.出銑時の溶湯温度 1550〜1570℃
3.溶湯の通道量 4〜5ton/分
【0014】
【発明の効果】
以上の実施例実用試験結果表4に示されるように現在一般に主として行われている比較品No3に対して、本発明品1,2の耐用はそれぞれ350%,385%と成る。また亀裂発生による溝状の異状損傷とは片べりする傾向も改善され安定した操業ができ、その上連続出銑操業が出来ると共に長寿命化が計れる。出銑口の開閉度数が少なくなり悪環境下での過酷な炉前作業が従来の約1/3となり、作業面、コスト面及び溶湯の品質が向上しバラツキの減少につながり作業面および生産費の低減と高い耐用寿命と高品質の溶湯を得ることが出来てその効果は絶大なるものがある。[0001]
[Industrial application fields]
The present invention relates to hot metal and / or an outlet of a blast furnace for allowing molten iron to flow out in the blast furnace.
[0002]
[Prior art]
The exit of the blast furnace is generally a plugging machine for clay-shaped, irregular-shaped refractories called mud materials in which silicon carbide and / or silicon nitride and carbonaceous materials are mixed with silicate and / or high alumina materials. It is blocked by press-fitting with (mud gun). And at the time of unloading, the opening is performed by punching an iron rod into a mud material whose opening is closed by an opening machine.
In recent years, the operation of blast furnaces has become highly productive by reducing fuel consumption and increasing the amount of tapping by blowing fuel such as heavy oil, pitch and pulverized coal together with hot air from the tuyere into the furnace, and the non-tapping time is short. As a result, the opening and closing work for the output has become frequent, and the degree of work under high heat has increased. In addition, the conventional mud material has a large amount of erosion and wear due to hot metal and hot metal at the time of brewing, and stable operation cannot be performed due to the increase in the diameter of the brewing iron. The result is an adverse effect. The current time required for the extraction is generally about 3 to 4 hours, and the number of extractions is about 5 to 6 times per day. In addition, since the opening and closing operation of the taphole is a work under high temperature and in a bad environment, this increase in work not only has many problems in terms of environmental hygiene and operational safety, but also stable taping cannot be performed. The main conditions of the main runner, skinmer section, hot metal, and slag gutter, etc., become severe, and the damage is severe, so the silicate material and / or the high alumina material is the main material as mentioned above, and the carbonaceous material However, a clay-like amorphous refractory material and mud material containing at least one of silicon carbide and silicon nitride materials are used, but the above problems have not yet been solved. In order to solve these problems, Japanese Patent Application Laid-Open No. 2-205610 discloses a method (hereinafter referred to as the prior art) for forming a spout with a cylindrical refractory attached to the spout. However, the cylindrical refractory that forms the spout suppresses the expansion of the spout at the time of the spout, enabling a long time spout and reducing the number of times the spout is opened and closed. However, it has higher hot strength and viscosity than the operating conditions of the cylindrical refractory used for this, and is excellent in wear resistance at high temperatures, and has low reactivity to hot metal and hot metal and Although it is necessary to have a high resistance to thermal stress and a property that is difficult to crack, a refractory material that can satisfy these requirements cannot be obtained, and even this method has achieved the current purpose. There is no current situation.
[0003]
[Problems to be solved by the invention]
In view of this situation, the present invention is a cylindrical refractory that can solve the above-mentioned problems, and has low chemical reactivity to hot metal and hot metal, high hot strength, high viscosity, and excellent wear resistance at high temperatures. In addition, it has high resistance to thermal stress, is hard to break, has a small expansion of the taps in use, enables stable taping for a long time, and can reduce the number of taps. The object is to provide a cylindrical refractory for the mouth.
[0004]
[Means for Solving the Problems]
As a result of diligent research to solve the above-mentioned problems, the inventors of the present invention have (1) higher hot strength and viscosity and higher wear resistance at high temperatures than the operating conditions of the blast furnace outlet. .
(2) The hot metal and the reactivity to the hot metal are small and the melting loss is small.
(3) High resistance to thermal stress and resistance to cracking.
As a satisfactory refractory material for the above three items, a silicon carbide material and a high refractory material containing 90% or more of Al 2 O 3 or a composite refractory material made of an alumina material are most suitable. As a result of various basic tests, it was found that the composition was refractory material. The material composition of the refractory contains SiC, Al 2 O 3 and SiO 2 as essential components as silicon carbide material 20 to 90% by weight, alumina material 5 to 50, mullite material 5 to 30% by weight. The total amount of SiC, Al 2 O 3 and SiO 2 is 90% or more, and the porosity is 15% or less.
[0005]
Next, the reason why the cylindrical refractory of the present invention is limited will be described.
(1) About 20 to 90% by weight of silicon carbide material
SiC is a high thermal conductivity material with high hot strength and hot wear resistance, so it has little melting loss and can suppress the occurrence of harmful cracks and cracks. Weakens and the hot wear resistance deteriorates. On the other hand, if it is 20% or less, the bonding force of the structure becomes weak, the strength is low and the thermal conductivity is lowered, the damage resistance and crack cracking resistance are deteriorated, and the service life is shortened.
( 2 ) About 5 to 50% by weight of the alumina (Al 2 O 3 ) material, Al 2 O 3 increases the corrosion resistance and strength. However, when the content is less than 5% by weight, the result of improving the bonding strength of the structure is small. If it exceeds 50% by weight, the heat spalling property is lowered and cracking is likely to occur.
(3) About 5 to 30% by weight of the mullite material, the mullite material increases the thermal shock resistance of the refractory itself and increases the hot temperature because it is a needle-like crystalline material. This is because if the effect is small and exceeds 30% by weight, the chemical erosion resistance is impaired.
(4) When the total content of SiC, Al 2 O 3 and SiO 2 is 90% or less, it will generally be a multi-component system depending on the mixed material, but heat resistance, corrosion resistance and hot strength will be reduced, and thermal shock resistance will be further reduced. This is because it causes a decrease in the service life and a decrease in the service life.
(5) When the porosity is 15% or more, the density of the structure is lowered, so that the degree of penetration of foreign matter into the structure is increased, the corrosion resistance is lowered, the groove crack is easily generated, and the hot wear resistance is increased. It becomes 15% or less by becoming low.
[0006]
【Example】
Next, examples of the cylindrical refractory according to the present invention will be described.
Examples of chemical composition values of materials used in the examples are shown in Table 1, and the particle size constitution of the cylindrical refractory is shown in Table 2.
[0007]
[Table 1]
[0008]
[Table 2]
[0009]
[Table 3]
[0010]
The examples of the present invention use various refractory materials shown in Table 1, and after adding and kneading 2 wt% of SiO 2 inorganic binder and 4.5 wt% of water as the particle size constitution shown in Table 2, this kneading The product is gradually put into the mold while vibrating the water-absorbing mold, filled and cured to the extent that it can retain its shape, then demolded and dried, and then fired at a maximum temperature of 1550 ° C for a total time of 65 hours. Table 3 shows the results together with comparative products.
[0011]
From the above results, Table 4 shows the results of actual furnace tests conducted at the blast furnace outlet using the inventive products 1 and 2 and comparative products No 2 and No 3 as test materials.
[0012]
[Table 4]
[0013]
As shown in Table 3, the present invention products 1 and 2 and the comparative product which is a mullite additive-free product as a comparative product considering the heat spalling resistance of the added amount of the mullite material with the silicon carbide material and the alumina material constant For No2, a cylindrical refractory having an inner diameter of 50 mm, an outer diameter of 120 mm, and a length of 500 mm is formed by the same manufacturing method as that of the prototype and fired at a maximum temperature of 1550 ° C. to produce a refractory for the blast furnace outlet. Two cylindrical refractories for the spout are used for actual use. Comparative product No. 3 is used as a conventional refractory mud material by direct press-fitting using a closing machine at the spout opening as well as for practical use. The use conditions are as follows.
1. Blast furnace capacity 2828cm 3
2. Molten metal temperature at the time of tapping 1550-1570 ° C
3. Molten metal passage 4-5ton / min [0014]
【The invention's effect】
As shown in Table 4 above, the practical use test results of the present invention products 1 and 2 are 350% and 385%, respectively, with respect to the comparative product No3 which is currently mainly performed. In addition, the tendency to break apart from the groove-like abnormal damage due to crack generation is improved, and stable operation is possible. In addition, continuous tapping operation can be performed and the life can be extended. The opening / closing frequency of the sprue opening is reduced, and the harsh pre-furnace work in a bad environment is reduced to about 1/3 of the conventional one, improving the work surface, cost and the quality of the molten metal, leading to a reduction in variation and the work surface and production costs. Can be obtained, a high service life and a high-quality molten metal, and the effect is enormous.
Claims (1)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP05645795A JP3714697B2 (en) | 1995-02-20 | 1995-02-20 | Blast furnace outlet |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP05645795A JP3714697B2 (en) | 1995-02-20 | 1995-02-20 | Blast furnace outlet |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH08225815A JPH08225815A (en) | 1996-09-03 |
JP3714697B2 true JP3714697B2 (en) | 2005-11-09 |
Family
ID=13027640
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP05645795A Expired - Fee Related JP3714697B2 (en) | 1995-02-20 | 1995-02-20 | Blast furnace outlet |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3714697B2 (en) |
-
1995
- 1995-02-20 JP JP05645795A patent/JP3714697B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JPH08225815A (en) | 1996-09-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN111574206A (en) | Anti-corrosion iron runner castable for large blast furnace | |
CN108083786B (en) | Anhydrous micro-titanium accumulated material for blast furnace taphole and preparation method thereof | |
US5411997A (en) | Mud material used for iron tap hole in blast furnace | |
JP3714697B2 (en) | Blast furnace outlet | |
CN114644512B (en) | Erosion-resistant submerged nozzle for continuous casting of special steel and preparation method thereof | |
JP3977900B2 (en) | Blast furnace outlet closing mud material | |
JP3766137B2 (en) | Low-carbon MgO-C refractory for vacuum degassing refining furnace | |
JP5168080B2 (en) | Unshaped refractories for vertical furnaces | |
JP3747948B2 (en) | Blast furnace outlet | |
JP2779514B2 (en) | Tuyere for blast furnace | |
EP0094342B1 (en) | Combination electrodes for the electric steel production with protective jacket of temperature resistant materials on its metal shaft | |
JP4234804B2 (en) | Plate brick for sliding nozzle device | |
KR960015652B1 (en) | Composition of mud | |
JP7557328B2 (en) | Manufacturing method of mag-carbon bricks for LF pots | |
JPS62260768A (en) | Refractories for blast furnace basin | |
JPH08231277A (en) | Mud material for closing tap hole of blast furnace | |
CN111673902A (en) | Preparation method and special equipment of high-strength wear-resistant iron runner material | |
JP4695354B2 (en) | Carbon-containing refractory brick | |
JP2024010280A (en) | Refractory brick and method for producing the same | |
JPH0465370A (en) | Casting material for molten pig iron pretreating vessel | |
JPH09296212A (en) | Lance for blowing gas | |
JPH07115956B2 (en) | Mud material for tapping of blast furnace | |
JP2002160981A (en) | Stopper for pig iron tap hole of blast furnace | |
JPH08157252A (en) | Refractory for molten iron preliminary treating vessel | |
JPH09235162A (en) | Tuyere ring for blast furnace and production thereof |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20040330 |
|
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: 20050823 |
|
A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20050823 |
|
R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
LAPS | Cancellation because of no payment of annual fees |