JPH0517208A - Production of coarse aggregate blended magnesia-carbon refractories - Google Patents
Production of coarse aggregate blended magnesia-carbon refractoriesInfo
- Publication number
- JPH0517208A JPH0517208A JP3192680A JP19268091A JPH0517208A JP H0517208 A JPH0517208 A JP H0517208A JP 3192680 A JP3192680 A JP 3192680A JP 19268091 A JP19268091 A JP 19268091A JP H0517208 A JPH0517208 A JP H0517208A
- Authority
- JP
- Japan
- Prior art keywords
- magnesia
- carbon
- coarse aggregate
- weight
- mgo
- 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)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、溶融金属容器の内張り
材として使用されるマグネシア・カーボンれんがの製造
方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a magnesia carbon brick used as a lining material for a molten metal container.
【０００２】[0002]
【従来の技術】ＭｇＯを主成分としたマグネシア・カー
ボンれんがは、優れた耐スポール性、耐スラグ侵食性を
有しており、転炉、ステンレス鋼溶製炉などの溶融金属
容器の内張り材として広く使用されている。しかし、転
炉、ステンレス鋼溶製炉などにおいて、精錬温度の上
昇、二次燃焼比率の上昇など、また溶融還元やスクラッ
プ溶解などの新しい操業方法によって、マグネシア・カ
ーボンれんがの使用条件を著しく過酷なものとしてい
る。このような条件下において、マグネシア・カーボン
れんがはスラグなどに対する高い耐食性を有することも
必要であるが、耐スポーリング性も不可欠の具備特性で
ある。耐スポール性の向上については特開昭６２−５６
３５４号公報にはカーボンの粒度や添加量の調整による
影響が記載されており、特開昭５８−２０４８６６号公
報にはピッチ添加との関係が、特公昭６２−９５５３号
公報にはカーボン質ファイバーの配合の効果が開示され
ている。2. Description of the Related Art Magnesia carbon bricks containing MgO as a main component have excellent spall resistance and slag erosion resistance, and are used as a lining material for molten metal containers such as converters and stainless steel melting furnaces. Widely used. However, in converters, stainless steel smelting furnaces, etc., the operating conditions of magnesia and carbon bricks have become extremely harsh due to rising refining temperature, increasing secondary combustion ratio, and new operating methods such as smelting reduction and scrap melting. I am supposed to. Under such conditions, the magnesia-carbon brick needs to have high corrosion resistance against slag and the like, but spalling resistance is also an essential property. Regarding the improvement of spall resistance, JP-A-62-56
Japanese Patent No. 354 discloses the effect of adjusting the particle size of carbon and the amount of carbon added, Japanese Patent Laid-Open No. 58-204866 discloses a relationship with pitch addition, and Japanese Patent Publication No. 62-9553 discloses carbon fiber. The effect of blending is disclosed.
【０００３】[0003]
【発明が解決しようとする課題】ところが、これらの耐
スポーリング性の向上手段はれんがの低かさ比重、低弾
性率化による低強度化をもたらす可能性が大きく、溶鋼
流に対する耐摩耗性やスクラップ投入などによる物理的
衝撃に対する抵抗性を極めて低下させる問題点がある。
最近の転炉、ステンレス鋼溶製炉などの溶融金属容器の
内張り材として広く使用されるマグネシア・カーボンれ
んがは、強度と耐スポール性のバランスが重要であり、
耐スポーリング性を向上させるために強度を犠牲にする
ことは実際の使用上好ましくない。However, these means for improving spalling resistance are likely to bring about a low bulk specific gravity of bricks and a low elasticity due to a low elastic modulus, and have a high wear resistance against molten steel flow and scrap. There is a problem that resistance to physical impact due to throwing in is extremely lowered.
The balance between strength and spall resistance is important for magnesia carbon bricks, which are widely used as lining materials for molten metal containers such as modern converters and stainless steel melting furnaces.
It is not preferable for practical use to sacrifice strength to improve spalling resistance.
【０００４】[0004]
【課題を解決するための手段】本発明者らは、前述の問
題点の解決を図って、マグネシア・カーボンれんがの組
織に着目し、粗骨材と微粉領域のバランスがれんが物性
に及ぼす影響を種々検討した。その結果、一般的には粗
骨材はマグネシアクリンカーが主体であるが、これにマ
グネシア・カーボン質粗骨材を採用することで、強度・
耐スポール性が大巾に向上することを見出した。すなわ
ち、主たる原料がＭｇＯで、カーボン５〜１５重量％、
Ａｌ、Ｍｇ、Ｃａ、Ｓｉの中の一種または二種以上或は
それらの合金を２〜１０重量％、フェノール系バインダ
ーよりなるマグネシア・カーボン質耐火性配合をあらか
じめ混練、成形、熱処理、粉砕して１０〜４０ｍｍの粗
骨材に調整して得られる粗骨材（Ａ）と、主たる原料が
ＭｇＯで、カーボン１０〜３０重量％、Ａｌ、Ｍｇ、Ｃ
ａ、Ｓｉの中の一種または二種以上或はそれらの合金を
２〜７重量％、フェノール系バインダーよりなるマグネ
シア・カーボン質耐火性配合（Ｂ）とを、混合比率が粗
骨材（Ａ）の混合率で１０〜４０重量％混合して、成
形、熱処理を施すことによって得られる粗骨材ブレンド
マグネシア・カーボン質耐火物の製造方法である。[Means for Solving the Problems] The inventors of the present invention have attempted to solve the above-mentioned problems, paying attention to the structure of magnesia-carbon bricks, and examined the effect of the balance between coarse aggregate and fine powder areas on the physical properties of bricks. Various studies were conducted. As a result, magnesia clinker is generally the main constituent of coarse aggregate, but by adopting magnesia / carbonaceous coarse aggregate, strength and
It has been found that the spall resistance is greatly improved. That is, the main raw material is MgO, and the carbon content is 5 to 15% by weight.
One, two or more kinds of Al, Mg, Ca, Si or their alloys are mixed in an amount of 2 to 10% by weight, and a magnesia-carbon refractory compound consisting of a phenolic binder is kneaded, molded, heat-treated and crushed in advance. Coarse aggregate (A) obtained by adjusting to coarse aggregate of 10 to 40 mm, and MgO as a main raw material, 10 to 30 wt% carbon, Al, Mg, C
a, 2 to 7% by weight of one or more of Si and alloys thereof, and a magnesia-carbon refractory compound (B) consisting of a phenolic binder in a mixing ratio of coarse aggregate (A) It is a method for producing a coarse aggregate-blended magnesia-carbonaceous refractory obtained by mixing at a mixing ratio of 10 to 40% by weight, molding and heat treatment.
【０００５】[0005]
【作用】マグネシア・カーボンれんがの耐スポーリング
性を向上させる手段の一つに粒度構成を粗化にしてれん
が組織の緻密化を抑制する方法がある。この場合、一般
的にはマグネシアクリンカーのトップサイズの拡大、ま
たは粗粒域の添加量増加などが実施される。しかし、マ
グネシアクリンカーは熱膨張率が大きく、また特に電融
マグネシアクリンカーのように表面が鏡面のように滑ら
かなものは黒鉛・金属・その他の添加物との物理的な接
着性に劣ると考えられる。本発明者らは耐スポーリング
性を向上させると同時に強度付与も狙って、粗骨材にマ
グネシア・カーボン質フェノール樹脂硬化体の採用に着
目した。その根拠は、前述のマグネシアクリンカーの特
性に比較して、熱膨張率は１０〜２０％低いこと、また
黒鉛・金属・その他の添加との物理的な接着性にも同材
質のため優れることである。[Function] One of the means for improving the spalling resistance of the magnesia-carbon brick is to make the grain structure coarse so as to suppress the densification of the brick structure. In this case, generally, the top size of the magnesia clinker is enlarged, or the amount of addition in the coarse grain region is increased. However, magnesia clinker has a large coefficient of thermal expansion, and in particular, the one with a smooth surface such as a mirror surface like electro-fused magnesia clinker is considered to have poor physical adhesion to graphite, metal and other additives. .. The present inventors focused on the adoption of a magnesia-carbonaceous phenolic resin cured product as a coarse aggregate in order to improve the spalling resistance and at the same time impart strength. The rationale is that the coefficient of thermal expansion is 10 to 20% lower than that of the above-mentioned magnesia clinker, and it is also excellent in physical adhesion to graphite, metal, and other additives due to the same material. is there.
【０００６】以下、発明の内容について詳細に述べる。
まず、粗骨材（Ａ）は高強度であることが重要である。
そのため原料はＭｇＯ主体で、カーボン５〜１５重量
％、Ａｌ、Ｍｇ、Ｃａ、Ｓｉの中の一種または二種以上
或はそれらの合金を２〜１０重量％、フェノール系バイ
ンダーよりなる。カーボンが５重量％より少ない場合、
熱膨張率や他原料との物理的な接着性の特徴が発揮され
ず、１５重量％より多い場合、強度面で劣る。Ａｌ、Ｍ
ｇ、Ｃａ、Ｓｉの中の一種または二種以上或はそれらの
合金が２重量％より少ない場合、強度面で劣り、１０重
量％より多い場合、メタルの過剰な反応により組織破壊
を生じる。粗骨材の粒度は１０〜４０ｍｍが望ましい。
粒度が１０ｍｍより小さい場合、従来のマグネシア・カ
ーボンれんがとほとんど同等の特性を示す粗骨材ブレン
ドの特徴が生かされず、４０ｍｍより大きい場合、粗骨
材ブレンドマグネシア・カーボンれんがの製造におい
て、セグリゲーションや成形性に問題がある。The details of the invention will be described below.
First, it is important that the coarse aggregate (A) has high strength.
Therefore, the raw material is mainly MgO, 5 to 15% by weight of carbon, 2 to 10% by weight of one or more of Al, Mg, Ca and Si or alloys thereof, and a phenolic binder. If the carbon content is less than 5% by weight,
The characteristics of the thermal expansion coefficient and the physical adhesiveness with other raw materials are not exhibited, and when it is more than 15% by weight, the strength is poor. Al, M
When the content of one or more of g, Ca and Si or their alloys is less than 2% by weight, the strength is inferior, and when the content is more than 10% by weight, excessive metal reaction causes structural destruction. The grain size of the coarse aggregate is preferably 10 to 40 mm.
When the particle size is smaller than 10 mm, the characteristics of the coarse aggregate blend exhibiting almost the same characteristics as the conventional magnesia-carbon brick are not utilized, and when the particle size is larger than 40 mm, the segregation or molding in the production of the coarse-aggregate magnesia carbon brick is performed. There is a problem with sex.
【０００７】耐火性配合（Ｂ）は、強度と耐スポーリン
グ性を有することが重要である。原料はＭｇＯ主体で、
カーボン１０〜３０重量％、Ａｌ、Ｍｇ、Ｃａ、Ｓｉの
中の一種または二種以上或はそれらの合金を２〜７重量
％、フェノール系バインダーよりなる。カーボンが１０
重量％より少ない場合、耐スポーリング性に劣り、３０
重量％より多い場合、強度・耐酸化性に劣る。Ａｌ、Ｍ
ｇ、Ｃａ、Ｓｉの中の一種または二種以上或はそれらの
合金が２重量％より少ない場合、強度・耐酸化性に劣
り、７重量％より多い場合、耐スポーリング性に劣る。It is important that the refractory formulation (B) has strength and spalling resistance. The raw material is mainly MgO,
10 to 30% by weight of carbon, 2 to 7% by weight of one or more of Al, Mg, Ca and Si or alloys thereof, and a phenolic binder. 10 carbon
If less than 30% by weight, the spalling resistance is inferior, and
If it exceeds 5% by weight, the strength and oxidation resistance are poor. Al, M
If the content of one or more of g, Ca, and Si or their alloys is less than 2% by weight, the strength and oxidation resistance are poor, and if more than 7% by weight, the spalling resistance is poor.
【０００８】粗骨材（Ａ）と耐火性配合（Ｂ）との混合
比率は粗骨材（Ａ）の混合率で１０〜４０重量％である
ことが望ましい。粗骨材（Ａ）が１０重量％より少ない
場合、従来のマグネシア・カーボンれんがとほとんど同
等の特性を示し粗骨材ブレンドの特徴が生かされず、４
０重量％より多い場合、粗骨材ブレンドマグネシア・カ
ーボンれんがの製造において、セグリゲーションや成形
性に問題がある。カーボンは天然または人造黒鉛、メゾ
フェイズカーボン、コークス、カーボンブラックなど
で、できるだけ高純度のものが望ましい。主たる原料で
あるＭｇＯはできるだけ高純度であることが好ましく、
電融品、焼結品などが使用可能であるが、ペリクレース
結晶系の大きいものが望ましい。以下、実施例に基づき
粗骨材ブレンドマグネシア・カーボンれんがの効果につ
いて説明する。The mixing ratio of the coarse aggregate (A) and the refractory compound (B) is preferably 10 to 40% by weight in terms of the mixing ratio of the coarse aggregate (A). When the content of coarse aggregate (A) is less than 10% by weight, it exhibits almost the same properties as conventional magnesia carbon bricks, and the characteristics of coarse aggregate blend are not utilized.
When it is more than 0% by weight, there is a problem in segregation and formability in the production of the coarse aggregate blended magnesia carbon brick. Carbon is natural or artificial graphite, mesophase carbon, coke, carbon black, and the like, and it is desirable that the purity is as high as possible. It is preferable that the main raw material MgO be as pure as possible,
Electrofused products and sintered products can be used, but those with a large periclase crystal system are preferred. Hereinafter, the effect of the coarse aggregate blended magnesia carbon brick will be described based on examples.
【０００９】[0009]
【実施例】表１に試作物性評価結果を示す。表中に示す
粗骨材（Ａ）の原料組成にそれぞれ液状のフェノール系
バインダーを粗骨材（Ａ）全量に対して２．７〜３．０
重量％の範囲内の必要量添加して混練、真空フリクショ
ン成形、乾燥（９０℃×２４ｈｒｓ）硬化処理（２５０
℃×１０ｈｒｓ）を施し、評価サンプルを得た。比較例
１、２、３及び４に示すようにカーボン、金属の添加量
が特許請求の範囲外であると実施例に比較して熱間強
度、焼成後の組織の点で劣っている。[Examples] Table 1 shows the evaluation results of physical properties of prototypes. A liquid phenolic binder is added to the raw material composition of the coarse aggregate (A) shown in the table, and the total amount of the coarse aggregate (A) is 2.7 to 3.0.
Add necessary amount within the range of wt%, knead, vacuum friction molding, dry (90 ° C. × 24 hrs) curing treatment (250
C. × 10 hrs) was applied to obtain an evaluation sample. As shown in Comparative Examples 1, 2, 3 and 4, when the amounts of carbon and metal added are out of the scope of the claims, the hot strength and the structure after firing are inferior to the Examples.
【００１０】また、粗骨材（Ａ）と耐火性配合物（Ｂ）
との配合物による粗骨材ブレンドマグネシア・カーボン
質耐火物についても、それぞれ液状、フェノール系バイ
ンダーを耐火性配合物（Ｂ）の全量に対して２．８〜
３．２重量％の範囲内の必要量添加して、混練、真空フ
リクション成形、乾燥（９０℃×２４ｈｒｓ）硬化処理
（２５０℃×１０ｈｒｓ）を施し、サンプルを得た。比
較例１〜４は前述の通りであり、５、６については粗骨
材（Ａ）の粒度の外れ、７、８、９及び１０は耐火性配
合物（Ｂ）におけるカーボン、金属の添加量が外れてお
り、１１、１２は粗骨材（Ａ）の量の外れにより亀裂が
生じ耐スポーリング性の点が劣っていることが認められ
る。Also, coarse aggregate (A) and refractory compound (B)
As for the coarse aggregate blended magnesia / carbon refractory prepared by blending with the above, liquid and phenolic binders are used in amounts of 2.8-based on the total amount of the refractory blend (B).
A necessary amount within the range of 3.2% by weight was added, and kneading, vacuum friction molding, and drying (90 ° C. × 24 hrs) curing treatment (250 ° C. × 10 hrs) were performed to obtain a sample. Comparative Examples 1 to 4 are as described above, 5 and 6 are out of the particle size of the coarse aggregate (A), and 7, 8, 9 and 10 are the addition amounts of carbon and metal in the refractory compound (B). It is recognized that the cracking is caused by the deviation of the amount of the coarse aggregate (A) and the spalling resistance is inferior.
【００１１】[0011]
【表１Ａ】 [Table 1A]
【００１２】[0012]
【表１Ｂ】 [Table 1B]
【００１３】[0013]
【表１Ｃ】 [Table 1C]
【００１４】[0014]
【表１Ｄ】 [Table 1D]
【００１５】[0015]
【表１Ｅ】 [Table 1E]
【００１６】[0016]
【発明の効果】本発明によって、以下の効果を奏するこ
とができる。従来のマグネシア・カーボンれんがの耐用
を向上させる手段の一つとして、マグネシア・カーボン
質粗骨材を採用することにより、技術的にかなり困難で
あった熱間強度、耐スポーリング性の両特性を同時に向
上させた。According to the present invention, the following effects can be obtained. As one of the means to improve the durability of conventional magnesia / carbon bricks, by adopting the magnesia / carbon coarse aggregate, both technical characteristics of hot strength and spalling resistance, which were technically difficult, were achieved. Improved at the same time.
─────────────────────────────────────────────────────
─────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成３年８月２０日[Submission date] August 20, 1991
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１１[Correction target item name] 0011
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１１】[0011]
【表１Ａ】 [Table 1A]
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１２[Correction target item name] 0012
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１２】[0012]
【表Ｂ】 [Table B]
【手続補正３】[Procedure 3]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１３[Correction target item name] 0013
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１３】[0013]
【表１Ｃ】 [Table 1C]
【手続補正４】[Procedure amendment 4]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１４[Correction target item name] 0014
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１４】[0014]
【表１Ｄ】 [Table 1D]
【手続補正５】[Procedure Amendment 5]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１５[Correction target item name] 0015
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１５】[0015]
【表１Ｅ】 [Table 1E]
───────────────────────────────────────────────────── フロントページの続き (72)発明者 駿河 俊博 福岡県北九州市八幡西区東浜町１−１ 黒 崎窯業株式会社内 (72)発明者 山本 博 福岡県北九州市八幡西区東浜町１−１ 黒 崎窯業株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshihiro Suruga 1-1 Higashihama-cho, Hachimansai-ku, Kitakyushu, Fukuoka Kurosaki Ceramics Co., Ltd. (72) Hiroshi Yamamoto 1-1 Black Higashi-hama-cho, Hachimansai-ku, Kitakyushu, Fukuoka Saki Ceramics Co., Ltd.
Claims (1)
５重量％、Ａｌ、Ｍｇ、Ｃａ、Ｓｉの中の一種または二
種以上或はそれらの合金を２〜１０重量％、フェノール
系バインダーよりなるマグネシア・カーボン質耐火性配
合をあらかじめ混練、成形、熱処理、粉砕して１０〜４
０ｍｍの粗骨材に調整して得られる粗骨材（Ａ）と、主
たる原料がＭｇＯで、カーボン１０〜３０重量％、Ａ
ｌ、Ｍｇ、Ｃａ、Ｓｉの中の一種または二種以上或はそ
れらの合金を２〜７重量％、フェノール系バインダーよ
りなるマグネシア・カーボン質耐火性配合（Ｂ）とを、
混合比率が粗骨材（Ａ）の混合率で１０〜４０重量％混
合して、成形、熱処理を施すことによって得られる粗骨
材ブレンドマグネシア・カーボン質耐火物の製造方法。Claims: 1. The main raw material is MgO and carbon 5 to 1
5% by weight, 1 to 2 or more of Al, Mg, Ca, Si or 2 to 10% by weight of an alloy thereof, and a magnesia-carbon refractory compound consisting of a phenolic binder are previously kneaded, molded and heat treated. , Crushed 10-4
Coarse aggregate (A) obtained by adjusting to 0 mm of coarse aggregate, the main raw material is MgO, carbon 10 to 30 wt%, A
Magnesia-carbonaceous refractory compound (B) consisting of 2 to 7% by weight of one, two or more of 1, 1, Mg, Ca and Si or an alloy thereof, and a phenolic binder (B),
A method for producing a coarse aggregate blend magnesia carbonaceous refractory obtained by mixing and mixing the coarse aggregate (A) at a mixing ratio of 10 to 40% by weight and subjecting to molding and heat treatment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3192680A JP3002296B2 (en) | 1991-07-08 | 1991-07-08 | Method for producing coarse aggregate blended magnesia-carbon refractory |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3192680A JP3002296B2 (en) | 1991-07-08 | 1991-07-08 | Method for producing coarse aggregate blended magnesia-carbon refractory |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0517208A true JPH0517208A (en) | 1993-01-26 |
| JP3002296B2 JP3002296B2 (en) | 2000-01-24 |
Family
ID=16295261
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3192680A Expired - Fee Related JP3002296B2 (en) | 1991-07-08 | 1991-07-08 | Method for producing coarse aggregate blended magnesia-carbon refractory |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3002296B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109503128A (en) * | 2018-12-28 | 2019-03-22 | 海城利尔麦格西塔材料有限公司 | A kind of high intensity converter mouth castable and preparation method |
-
1991
- 1991-07-08 JP JP3192680A patent/JP3002296B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109503128A (en) * | 2018-12-28 | 2019-03-22 | 海城利尔麦格西塔材料有限公司 | A kind of high intensity converter mouth castable and preparation method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3002296B2 (en) | 2000-01-24 |
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