JP3729495B2 - Baking repair material - Google Patents

Description

【００２５】
（式中、ｎは２以上の整数）
で示され、融点が４４〜１００℃、好ましくは６０〜８４℃のものである。ｐ−アルキルフェノールは、塩化アルミニウム、硫酸、フツ化水素酸、フツ化瑚素等の存在下、エチレン系炭化水素とフェノールを反応させて工業的に得られるもので、下記の表１に示すものが例示される。
【００２６】
【表１】

【００２７】
また、ビスフェノールとしては、一般式
ＨＯ−Ｃ₆ Ｈ₄ −Ｃ（Ｒ）（Ｒ′）−Ｃ₆ Ｈ₄ −ＯＨ
（式中、Ｒ、Ｒ′は水素、アルキル基であり、同一でも異なっていてもよい。）で示されるものである。具体的には、Ｒ、Ｒ′が共にメチル基であるビスフェノールＡ（融点１５５〜１５７℃）、Ｒ、Ｒ′が共に水素であるビスフェノールＦ等が挙げられる。
【００２８】
また、ラクタム類の中ではε−カプロラクタムが焼付材の燃焼性、展開性の向上に効果的であり、粉末状焼付材にも使用されている。焼付材のブリケット化による硬化遅延を防止するためにラクタム類を添加する場合はε−カプロラクタム（ｍ．ｐ．６９℃）の添加が望ましい。他にジフェニル（ｍ．ｐ．６９℃）、ジフェニルアミン（ｍ．ｐ．５２℃）も例示される。
【００２９】
焼付助剤であるｐ−アルキルフェノール類、ラクタム類、ビスフェノール、ジフェニル、ジフェニルアミン類として、粉末状として市販されているものを使用するとよい。
【００３０】
次に、ワックスは、常温では固体で融点以上の温度にすると粘性が非常に低い液体となることが挙げられ、溶解したワックスは熱間で材料に流動性を与える効果があることより、融点以下ではプリケット成形用バインダーとして作用し、融点以上では焼付材の展開性、接着性を促進する等の優れた特性を持つものである。ワックスは、天然ワックス、合成ワックスに分類され、さらに動植物系、鉱物系、石油系など細かく分類される多種多様なものであり、市販されている各種のものが使用可能であるが、本発明におけるワックスとしては、その融点が熱間バインダーの融点よりも低いものである。
【００３１】
使用できるワックスにおける融点の下限値については、製造されるブリケット焼付材が保管中に接する雰囲気温度よりも高ければよい。例えば、転炉用の焼付材は夏季の現場保管中に４０〜５０℃となる可能性があるため、５０℃以上のものとするとよく、また、上述した熱間バインダーの融点１００℃〜３００℃のものより低くいものであり、例えばパラフィンワックス（ｍ．ｐ．５３℃）、モンタンワックス（ｍ．ｐ．８５℃）等が例示される。
【００３２】
ワックスは常温において固形であるが、粉末状のものも市販されているので、適宜使用できる。加温した焼付材にワックスを溶かして添加混練する場合は、固形状、粉末状どちらでも使用可能である。また、予め焼付材粉末にワックスを混合した後加温混練する場合は、粉末状のワックスを使用するのがよい。粉末は細かいほど混練時間が短くてすむ。
【００３３】
成形用バインダーとして、ワックス又は、該ワックスと焼付助剤とを用いる本発明のブリケット状焼付補修材の特徴として、熱間投入時に材料中の成型用バインダーが先に溶融し、その後、フェノール樹脂粉末、石炭系ピッチなどの熱間バインダーに引火・溶融することにより初期発煙抑制効果が得られることが挙げられる。すなわち、成型用バインダーと熱間バインダーとの溶融時期の差が初期発煙の抑制を可能とするものであるが、ブリケット１個当りの体積が初期発煙の抑制に影響を与えることが見いだされ、初期発煙の抑制に適したブリケット１個当たりの体積は５×１０^-6〜１２００×１０^-6ｍ³ とするのがよいことが見いだされた。また、ブリケットの形状としては球状、角柱状、アーモンド状、円柱状等で特に問わない。
【００３４】
ブリケット１個当りの体積が、５×１０^-6ｍ³ 未満の場合はブリケット内部に瞬時に熱が伝わるため、成型用バインダーと熱間バインダーがほぼ同時に溶融し、初期発煙抑制効果が得られにくい。−方、ブリケット１個当りの体積が１２００×１０^-6ｍ³ より大きい場合は、ブリケットの内部まで熱が伝わるのに時間がかかり、初期発煙抑制効果は得られるものの、材料の硬化時間が遅くなり操業に支障をきたす恐れがある。
【００３５】
本発明のブリケット状焼付補修材にあっては、焼付助剤とワックスを同時に用いることにより、どちらか一方のみを使用する場合に較べ、材料の熱間流動性が向上し、短時間で広範囲の焼付が可能となるが、特に、焼付助剤は熱間バインダーとの相溶性に優れると共に、ワックスに比して燃焼性に優れているので、ブリケット化による硬化遅延現象を防止することを可能とするものであり、特に、焼付助材の添加量は重要な意味を持つ。
【００３６】
ｐ−アルキルフェノール類、ラクタム類、ビスフェノール、ジフェニル、ジフェニルアミンから選ばれる１種または２種以上の焼付助剤は、ワックスに較べて熱間での燃焼が激しいため、ブリケットサイズが大きい場合は補修時間の遅延を防止する効果が得られるのに対し、ブリケットサイズが小さい場合はブリケット内部に瞬時に熱が伝わるため、投入初期の発煙が激しくなる恐れがある。
【００３７】
このため、製造するブリケット１個あたりの体積により最適な焼付助剤の添加量を変えるとよい。ブリケット１個当たりの体積が５×１０^-6〜３００×１０^-6ｍ³ の範囲では、焼付助剤の添加量は耐火骨材と熱間バインダーとの合量に対して外掛けで０. ２〜５重量％が適当である。また、ブリケット１個当たりの体積が３００×１０^-6〜１２００×１０^-6ｍ³ の範囲では焼付助剤の添加量は耐火骨材と熱間バインダーとの合量に対して外掛けで５〜８重量％とするのがよい。元々、焼付補修材中には、上記の焼付助剤の項で記載したように展開性向上、接着性向上、炭化促進を目的として焼付助剤が添加されるが、ブリケット化による硬化遅延を避けるためには、本発明におけるブリケット状焼付補修材においては上記範囲内の焼付助剤の添加量とすることが必要である。
【００３８】
また、ワックスの添加量は、成型用バインダーとしてワックス単独とする場合には、ワックスを除くブリケット状焼付補修材１００重量部に対して外掛けで２．５〜１２重量部とするとよい。ワックスの添加量が１２重量部より多いと、施工体としての気孔率が増大し、強度が低下する等の問題が生じる。また、焼付助剤が成型用バインダーとして利用される場合には、ワックスの添加量は、上述したワックス単独とする場合の添加量から成型用バインダーとして機能する焼付助剤の添加量を差し引いた量を添加量とすることができるが、ワックスを除くブリケット状焼付補修材１００重量部に対して外掛けで少なくとも１重量部はワックス分とするとよく、これにより、成型体の強度を強固なものとでき、また成型性に優れるものとできる。
【００３９】
混練温度を焼付助剤の溶融温度以上にすれば、液状になった焼付助剤が成型用バインダーとして機能するので、焼付助剤添加量の分だけワックスの添加量を少なくすることができ、施工体の気孔率増加を抑制できる。特に、ブリケットサイズが大きくなると焼付助剤添加量を増加する必要があるので、焼付助剤の溶融温度以上での混練は耐用性低下防止に効果的である。
【００４０】
一方、３００×１０^-6ｍ³ 以下のサイズでブリケットを製造する場合は、焼付助剤の添加量も少なくて済むので、焼付助剤は粉末として材料中に混合し、ワックスを単独で成型用バインダーとしてもよい。従って、サイズの小さなブリケットを製造する場合は、焼付助剤よりも融点が低いワックスを使用して混練温度を低くすることが可能である。
【００４１】
その他、本発明のブリケット状焼付補修材には、金属粉末を添加することも可能である。金属粉末としてはＡｌ粉末が適当であるＡｌ粉末は酸化による発熱量が高く硬化促進に効果があり、生成するＡｌ₂ Ｏ₃ は高い耐熱性を有する。特に、耐火骨材にＭｇＯが配合されている場合は、ＭｇＯとの反応によりスピネルを生成することにより更なる耐用性の向上を期待できる。添加量としては、耐火骨材１００重量部に対して１〜１０重量部の範囲がよい。
【００４２】
次に、本発明のブリケット状焼付補修材の成型方法について説明する。
【００４３】
本発明のブリケット状焼付補修材は、耐火骨材、熱間バインダー、焼付助剤、ワックス等からなるが、焼付助剤における融点がワックスの融点より大きい場合には、混練温度を焼付助剤の融点以下として、混練温度以下に融点を持つワックスを成型用バインダーとして混練するとよく、これにより、混練温度を低くできる。また、ワックスと共に焼付助剤を成型用バインダーとして機能させることができるが、その場合には、予め両者の溶融温度以上に加熱して共に溶融した後、耐火骨材と熱間バインダーとからなる粉末状材料に添加、混練するとよく、また、ワックスと焼付助剤とを共に粉末のまま耐火骨材と熱間バインダーとからなる粉末材料中に投入した後、ワックスと焼付助剤の両者の溶融温度以上の温度で加温混練してもよい。
【００４４】
混練した材料を成型するには、金枠成型法、押し出し成型法、ペレタイジング法、ＣＩＰ成型法などいずれも使用可能であるが、中でも一対のモールドロールを有し、同期回転により混練材料を挟み込んで加圧成型するタイプのブリケットマシンを用いることにより連続的にブリケット化するとよく、生産性が向上する。ブリケットマシンを用いて成型する場合、使用するバインダーによっては低い成型体強度しか得られず少しの衝撃で成型体が崩壊したり、モールドロールヘの面付きにより所定の形状に成型できなかったりといった障害が生じることがあるが、ワックスを含有させることで高強度の成型体を製造することができる。更に、ワックスが有する滑材としての特徴がモールドロールヘの材料の面付きを完全に防止することができるといった優位性を有している。従って、本発明のブリケット状焼付補修材はモールドロールによる連続成型に最適なものといえる。また、モールドロールにも様々な種類があり、ブリケットの形状や寸法を変えることが可能である。また、本発明で用いるワックス及び焼付助剤は、それぞれの融点以上に加温することにより低粘性の液体となるため、石炭系タールなどに較べて少ない添加量で焼付材粉末を濡らすことができる。
【００４５】
モールドロールにてブリケツト状に成型する場合を含め、本発明のブリケット状焼付補修材における成型用バインダーの添加量としては、ワックス単独、または焼付助剤とワックスとの合量として、成型用バインダーを除くブリケット状焼付補修材１００重量部に対して外掛けで２．５〜１２重量部、好ましくは３〜１０重量部が望ましい。２．５重量部未満の添加量では充分な成型体強度が得られず、フレコンなどへの袋詰めの工程や少しの衝撃でブリケットが崩壊する危険性がある。また、１２重量部を超える添加量では、熱間施主時の揮発分が増加するため施工体組織がポーラスとなり、耐用性の低下を招く恐れがある。
【００４６】
本発明で製造するブリケット状焼付補修材は、転炉などに投入されたときに速やかに補修部位に移動できるような形状に成型するのがよい。球状に成型するのが最も望ましいが、角柱状、アーモンド状、円柱状などに成型しても転がりを付与できる。
【００４７】
以下に、実施例、比較例を示し、本発明のブリケット焼付材について具体的に説明するが、本発明はこれら実施例や説明によって限定されるものではない。
【００４８】
【実施例】
表２、表３、表４に実施例及び比較例におけるそれぞれの配合（重量％）および後述するテスト方法による結果を示す。
【００４９】
本発明である実施例１〜７は、融点の異なるワックスを用い、焼付助剤としてｐ−オクチルフェノールを使用して成型した１個当たりの体積が５×１０^-6〜３００×１０^-6ｍ³ のブリケット試料であり、実施例８〜１４は、１個当たりの体積が３００×１０^-6〜１２００×１０^-6ｍ³ の範囲で各種焼付助剤を使用して成型したブリケット試料である。比較例１は、ブリケット１個当たりの体積が５×１０^-6ｍ³ 未満で、焼付助剤を添加しない試料である。また比較例２は、成型用バインダーとして無水タールを用いて成型したブリケット試料である。また、比較例３〜５にブリケット化していない従来のドライタイプ、セミウェットタイプ、半固形タイプを示した。比較例６は１個当たりの体積が３００×１０^-6〜１０００×１０^-6ｍ³ の範囲で、焼付助剤を添加していない試料である。
【００５０】
実施例１〜７の成型方法を、実施例１により説明すると、耐火骨材としてＭｇＯ粉末（粒径０．３ｍｍ以下が３０重量％）８５重量部とコールタールピッチ粉末（ｍ．ｐ．１１０℃）１５重量部、ｐ−オクチルフェノール（ｍ．ｐ．８４℃）０．５重量部とからなる焼付材を成型温度と同じ６０℃に加温した後、パラフィンワックス（ｍ．ｐ．５３℃）３重量部を溶かして混合・混練した。成型装置は油圧式ハンドプレスを使用し、成型温度６０℃、成型圧５０Ｍｐａとし、直径３０ｍｍの円柱状ブリケット（１個当りの体積３３．５×１０^-6ｍ³ ）を試作した。実施例２〜７においては、各成分の添加量、成型温度、体積を表２に示すように変更した以外は、実施例１と同様である。
【００５１】
また、実施例８〜１５の成型方法においては、実施例８により説明すると、耐火骨材としてＭｇＯ粉末（粒径０．３ｍｍ以下が３０重量％）８５重量部とコールタールピッチ粉末（ｍ．ｐ．１１０℃）１５重量部とからなる焼付材を成型温度と同じ９５℃に加温した後、パラフィンワックス（ｍ．ｐ．５３℃）２重量部とｐ−オクチルフェノール（ｍ．ｐ．８４℃）６重量部とを溶かして混合・混練した。成型装置は油圧式ハンドプレスを使用し、成型温度９５℃、成型圧５０Ｍｐａとし、金型のサイズを変更することにより、直径６０ｍｍの円柱状ブリケット（１個当りの体積５２３．６×１０^-6ｍ³ ）を試作した。実施例９〜１５においては、各成分の添加量、成型温度、試料の体積を表２に示すように変更した以外は、実施例８と同様である。
【００５２】
なお、焼付補修材における成型用バインダーの添加量は、成型用バインダーを除くブリケット状焼付補修材１００重量部に対して、実施例１においては、２．９９重量部、実施例２においては、６．９７重量部、実施例３においては、７．５重量部、実施例４においては、１０．５重量部、実施例５においては、６．８重量部、実施例６においては、６．９７重量部、実施例７においては、７．５重量部、実施例８においては、８．０重量部、実施例９においては、８．０重量部、実施例１０においては、８．０重量部、実施例１１においては、７．５５重量部、実施例１２においては、８．０重量部、実施例１３においては、８．０重量部、実施例１４においては、８．０重量部、実施例１５においては、１０．０重量部、比較例１においては、７．０重量部、比較例２においては、８．５重量部である。
【００５３】
次に、各種焼付材のテスト方法について説明する。
【００５４】
まず、ブリケット状焼付補修材の成型体強度は、荷重を加え破壊が起きた時の荷重（ｋｇｆ／ｃｍ² ）により測定し、１０ｋｇｆ／ｃｍ² を超える場合を「極強」とし、５〜１０ｋｇｆ／ｃｍ² の場合を「強」、５ｋｇｆ／ｃｍ² の場合を「中」とした。また、経時変化については試料をビニール袋に入れ、２５℃の状態で１週間放置し、その成型体強度を同様に測定し、経時変化がない場合を「なし」とし、成型体強度が低下した場合を「強度低下」とした。
【００５５】
焼付特性の測定は、展開テストを図１に示す方法で、また、接着テストを図２に示す方法で行った。なお、図１〜図３には、試料７を球形状に図示するが、試料の形状は円柱状である。
【００５６】
図１（ａ）は展開テストに使用した箱型加熱炉の断面模式図であり、図中１は箱型加熱炉、２は上蓋、３はバーナー、４ａはプレート部、５はプレート受け台、６は面積０. １ｍ² のプレートである。図１（ｂ）はプレート部４ａの拡大図であり、７は試料を示す。図１（ｃ）は試料が溶融−展開−硬化した状態を示す図である。
【００５７】
展開テストは、図１に示すように、まず、面積０. １ｍ² のセラミックス製のプレートをあらかじめ箱型炉で加熱しておき、炉の上蓋を開け、プレート表面温度が１０００℃の時、試料８００ｇをプレート上に投入する。ブリケット試料は正確に８００ｇとすることができないので、８００ｇを超えない範囲でブリケット試料を計り取った後、崩壊したブリケット試料を加えて、８００ｇとなるように微調整を行った。
【００５８】
試料の硬化後、すばやく試料をプレートごと取り出し、展開後の試料の直径をノギスにて測定し、展開性とした。また、試料周囲の反り有無を目視により確認すると共に、試料を鉄ヘラを使用してプレート表面から剥がし落とす時の剥がし難さ及び材料強度を判定した。また、材料組織を目視観察により判定し、空洞のないものを良好とした。また、回収した試料片について見掛け気孔率を測定した。
【００５９】
図２（ａ）は、実施例１〜７、比較例１〜５で作製した試料の接着テストに使用した箱型加熱炉の断面模式図であり、図中１は箱型加熱炉、２は上蓋、３はバーナー、４ｂはプレート部、５はプレート受け台、８は面積０. ０１ｍ² のプレートである。図２（ｂ）はプレート部４ｂの拡大図であり、９は鉄製円筒金枠（φ７０ｍｍ）を示す。図２（ｃ）は１５０ｇの試料１０をプレート８上に投入する時の状態を示す。図２（ｄ）は試料が溶融−硬化した後、剪断強度を測定する状態を示す。
【００６０】
接着テストは、図２に示すように、まず、面積０. ０１ｍ² のセラミックス製プレートをあらかじめ箱型炉で加熱しておき、炉の上蓋を開け、プレート表面温度が１０００℃の時、鉄製円筒金枠をプレートの上に素早く置き、金枠の中に試料を１５０ｇ（体積約７０×１０^-6ｍ³ ）投入する。１５０ｇの採取方法は展開試験の場合と同じである。
【００６１】
試料の溶融から硬化までの時間を測定した。このとき、材料投入時の発塵の有無を目視により判定した。また、材料投入後１０秒後、１分後・・６分後における発煙量の推移を目視により測定した。なお、発煙量は、最大に発煙した状態を１００％とし、５０％とは最大に発煙している状態の５０％の状態とした。また、硬化後素早く試料をプレート、金枠ごと取り出し、プレートと金枠の剪断強度を測定し、剪断接着強度（ＭＰａ）を求め、耐ハクリ性を評価した。
【００６２】
以上の焼付テストにおいて、展開性、耐剥離性、材料強度、硬化時間、接着強度の各熱間特性は、下記の表５に示す判定記号を用いて評価した。実機における施工性、耐用性は各熱間特性を総合的に考慮して比較される。
【００６３】
ブリケット１個当りの重量が１５０ｇ（体積約７０×１０^-6ｍ³ ）を超える試料についての硬化時間は、図２で行った硬化時間測定が出来ないため、図３に示す方法により測定した。
【００６４】
図３（ａ）〜（ｃ）は、実施例８〜１５、比較例６で作製した試料の接着テストに使用した箱型加熱炉の断面模式図である。図中１は箱型加熱炉、２は上蓋、３はバーナー、４ｂはプレート部、５はプレート受け台、８は面積０．１ｍ² のプレートである。図３（ｂ）はプレート部４ｂの拡大図であり、９は鉄製円筒金枠（φ１５０ｍｍ）を示す。図３（ｃ）は試料１０をプレート８上に投入する時の状態を示す。
【００６５】
面積０．１ｍ² のセラミックス製プレートをあらかじめ箱型炉で加熱しておき、炉の上蓋を開け、プレート表面温度が１０００℃の時、鉄製円筒金枠（φ１５０ｍｍ）をプレートの上に素早く置き、金枠の中にブリケット試料１個を投入する。試料の溶融から硬化までの時間を、焼付助剤を添加しない成型前の粉末試料（ブリケット試料と等量）と比較した。
【００６６】
実施例８と対比される比較用の粉末試料は、耐火骨材としてＭｇＯ粉末（粒径０．３ｍｍ以下が３０重量％）８５重量部とコールタールピッチ粉末（ｍ．ｐ．１１０℃）１５重量部とからなる焼付材を９５℃に加温した後、パラフィンワックス（ｍ．ｐ．５３℃）２重量部を溶かして混合・混練したものを、実施例８によるブリケット試料と等量としたものであり、それぞれ、図３に示す接着テストにより比較し、実施例８による試料の相対硬化時間を測定した。発塵の有無、相対発煙量は図２と同様に目視により測定した。実施例９〜１５、比較例６も同様である。
【００６７】
【表２】

【００６８】
【表３】

【００６９】
【表４】

【００７０】
【表５】

【００７１】
表３に示す実施例１〜７より、成型用バインダーとして融点の異なるパラフィンワックス、モンタンワックスを用いて成型したブリケット試料は、添加量が２．５〜１２重量％の範囲で十分な成型体強度を持つことが確認できる。さらに、ブリケット品を１週間放置した後も全く経時変化がなく、保管性に優れていることがわかる。
【００７２】
接着テストにおいて硬化時間の遅延もなく、全試料において５分以下であった。展開テストにおける耐剥離性は強く、特にｐ−オクチルフェノールを３重量％添加した実施例５は非常に強い耐剥離性を示している。Ａｌ粉末を添加した実施例６においては優れた材料強度を示すことが分かる。発塵は全くなく、ブリケット化の効果が確認される。
【００７３】
接着テストにおける発煙量の推移に関し、ワックスで成型したブリケット品は、材料投入直後の発煙が完全に防止されていることが分かる。ワックスの熱による溶融とともに、徐々にコールタールピッチ等の熱間バインダーに引火して行き、投入から２〜４分後に発煙のピークを迎えるが、その後、すぐに発煙量が減少して行き、５〜６分で殆ど発煙がなくなっている。実施例７はブリケット１個当たりの体積を８. ２×１０^-6ｍ³ （１９ｇ）としたものであり、硬化時間が短縮されていることが分かる。
【００７４】
比較例１は、ブリケット１個当たりの体積を４. ２×１０^-6ｍ³ （１０ｇ）とし、焼付助剤を添加しなかったものであるが、投入１０秒後ですでに発煙が多量に発生し、展開性の低下、硬化時間の遅延が見られた。比較例２は、無水タールを成型用バインダーとしてブリケット化した配合であり、成型直後はある程度の強度を持っていたが、１週間の放置により、脆化してしまった。比較例３、４は現在各所で使用されているドライ及びセミウェットタイプのものであり、展開性、接着性に優れているが、ドライタイプにおいては熱間投入時に多量に発塵し、投入直後から激しく発煙した。また、セミウェットタイプは発塵量がある程度抑えられるものの、ドライタイプと同様に熱間投入直後から激しく発煙した。比較例５は、無水タールにより混練した可塑性半固形タイプであるが、施工体表面付近に空洞が発生し、また、材料投入後６分経過しても発煙が続いた。
【００７５】
表５に示すように、ブリケット１個当たりの体積が約７０×１０^-6ｍ³ （１５０g ）を超える試料について、発塵の有無及び発煙量の推移を測定した結果、ｐ−オクチルフェノールを６重量％添加して５２３. ６×１０^-6ｍ³ （１２００ｇ）に成型した実施例８及び、ｐ−オクチルフェノールを７重量％添加して８４６. ０×１０^-6ｍ³ （２０００ｇ）に成型した実施例９のいずれも、投入初期の激しい発煙を抑制する効果が確認できる。また、ｐ−オクチルフェノール以外の焼付助剤を使用した実施例１０〜１２も同様に、投入初期の激しい発煙を抑制する効果が確認できる。これらの実施例８〜１２はブリケット１個の体積が大きく、重量も１ｋｇを超えるため、発煙が終了するまでの時間が長くなるが、焼付助剤を添加しない成型前の粉末試料との硬化時間の比較を示した相対硬化時間（比較用の粉末試料＝１００とする）を見れば、硬化時間の遅延を抑制する効果が確認できる。
【００７６】
また、ｐ−オクチルフェノール添加量を４重量％とし、ブリケット１個あたりの体積を５２３. ６×１０^-6ｍ³ 及び８４６. ０×１０^-6ｍ³ とした実施例１３、１４は、若干の硬化時間の遅延があるが、熱間投入直後の発煙は完全に防止されている。実施例１５は、ブリケット１個あたりの体積が１０００×１０^-6ｍ³ を超える場合であり、実施例１３ 、１４と同様、若干の硬化時間の遅延があるが、熱間投入直後の発煙は完全に防止されている。また、実施例８〜１５に対し、焼付助剤を添加せずワックスのみを使用して成型した比較例６は、硬化時間が大幅に長くなる結果となった。
【００７７】
【発明の効果】
本発明のブリケット焼付補修材は、焼付助剤の適量をブリケット状焼付補修材中に含み、常温では固体で加熱により溶融するワックス又は、該ワックスと焼付助剤とを成型用バインダーとして使用してブリケット状に成型することにより、従来の粉末状焼付材の熱間特性を損なうことなく、投入時の発塵、発煙を防止することが可能となり、作業環境が大幅に改善できる。
【図面の簡単な説明】
【図１】 図１は、焼付特性における展開テストに際しての試験炉及び試験方法の概説図である。
【図２】 図２は、焼付特性における接着テストに際しての試験炉及び試験方法の概説図である。
【図３】 図３は、ブリケット１個当りの重量が１５０g を超える試料の焼付テストに際しての試験炉及び試験方法の概説図である。
【符号の説明】
１は箱型加熱炉、２は上蓋、３はバーナー、４ａ、４ｂはプレート部、５はプレート受け台、６は面積０. １ｍ² のプレート、７は試料、８は面積０．０１ｍ² のプレート、９は鉄製円筒金枠、１０は試料である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a baking repair material used in a metal smelting furnace or a molten metal container and a method for producing the same, and particularly aims at improving the working environment.
[0002]
[Prior art]
Hot baking materials used for repairing various refining furnaces such as converters, electric furnaces, AOD furnaces, LF pots, and furnace bottoms are refractory aggregates such as magnesia and dolomite, phenolic resin, and coal-based tar. , Coal pitch, various fluidization aids, development aids, combustion aids, and optionally various additives such as metals. Hot bake material uses the residual heat of the kiln, for example, in a converter, the bake material is introduced from the furnace port immediately after the hot steel is discharged, and after flowing and spreading, it is cured and bonded at a predetermined damaged point. By coating, it has the effect of protecting the damaged part.
[0003]
The material is composed of (1) a wet type that is kneaded in a slurry form with a low-viscosity liquid phenol resin, (2) a plastic semi-solid type (kneader material) that is kneaded with a high-viscosity coal-based tar, and (3) a phenol resin. Dry type that mixes powdery binders such as powder and coal-based pitch with aggregates, and (4) Dry type baking materials with rapeseed oil, soybean oil, heavy oil etc. for the purpose of suppressing dusting to some extent A semi-wet type with a small amount added is used.
[0004]
In the wet type kneaded into the slurry form of (1), sedimentation and separation of aggregates during transportation and storage, and characteristic changes due to aging of the phenol resin are likely to occur. In Japanese Patent Publication No. 5-41594 and Japanese Patent Publication No. 6-31161, a method of adding powdered paraffin is described as a measure against the sedimentation and separation of aggregates. The usable period is as short as two months or less. The plastic semi-solid type (kneader material) (2) requires a high-power kneader mixer for kneading, and requires a longer hot work time compared to the dry and semi-wet types. There are drawbacks such as being easily disturbed. On the other hand, compared with the kneader material of (2), the dry type of (3) and the semi-wet type of (4), which were initially low in terms of shortening of the curing time and adhesive strength and hot developability, were obtained. Through repeated improvements, durability equal to or higher than that of a kneader material can be obtained, and it can be manufactured relatively easily by mixing a powdered binder with an aggregate. Currently, hot repairs using (3) dry type or (4) semi-wet type baking materials are possible due to relatively little change and better suitability for long-term storage than wet type and plastic semi-solid type. It has become mainstream.
[0005]
A method of adding lactams as a powdered binder (Patent No. 2555550), a method of adding diphenyl or diphenylamine for the purpose of shortening the curing time and improving durability by improving the adhesive strength and hot developability of powdered baking materials (Japanese Patent Laid-Open No. Hei 8-169772), a method of adding bisphenol or p-alkylphenol (International Publication WO 98/50321), and the like have been proposed and the intended purpose has been achieved. These powdery baking materials are basically supplied in combustible bags such as flexible containers, and when placed in a furnace such as a converter where the repair temperature exceeds 1000 ° C, the powdery binder is instantly ignited. Combustion starts. The hot air generated at this time causes the fine powder and binder powder in the material to rise and burns more intensely. Usually, the converter equipment has a dust collector to collect dust and smoke, but when the baking material is put in, the converter is tilted, so the baking material is put away from the duct position of the dust collector. Will be. For this reason, fine powder in the material and soot generated by incomplete combustion are scattered to the surroundings, and the working environment is greatly deteriorated, and there is a possibility of adversely affecting the environment outside the factory. By making the material semi-wet, dust generation and smoke generation can be suppressed to some extent, but the effect is not satisfactory.
[0006]
Japanese Patent Application Laid-Open No. 4-170370 and Japanese Patent Publication No. 6-46142 propose a method of adding wax to a baking material, but the effect is similar to that of the aforementioned lactams, diphenyl, diphenylamine and the like. In addition, it is expected to improve adhesive strength and hot spreadability, and no effect of suppressing dust generation and smoke generation at the time of material input is obtained.
[0007]
Japanese Patent Laid-Open No. 9-87725 proposes a method of using phenol resin powder and / or pitch powder, terpene resin, and wax powder in combination as a method of reducing the amount of smoke generated during hot repair of a baking material. Since it is a powder material, it is impossible to suppress smoke and dust generation immediately after hot addition. In order to suppress dust generation and not start intense combustion immediately after charging, a semi-solid type method like a kneader material is appropriate, but the above-mentioned disadvantage (necessary long construction time between hot, There is currently no type that can overcome (prone to hinder operations). In addition, coal-based tar is known to be highly viscous and sticky, and can be used as an adhesive. Although there was a period when it was used, the extension of the hardening time by coal-based tar use cannot be suppressed, and it is hardly used now.
[0008]
Japanese Patent Application Laid-Open No. 63-74973 describes a method of forming a powdered baking material into a small briquette shape using paraffin as a binder for the purpose of smoke generation and oxidation prevention during hot construction. However, there is a problem that the construction time is longer than that of the powdered baking material.
[0009]
[Problems to be solved by the invention]
Based on the above problems, the problem to be solved by the present invention is that the dry type and semi-wet type baking materials have high hot characteristics and durability, and the sedimentation and separation of aggregates found in wet type baking materials. Dust is suppressed when the material is thrown in between 1000 ° C and over, and there is no worry about the trouble of operation due to long-term repair of binders and long-term repair found in kneader materials. It is in the point which provides the baking material for repair which has the hardening time equivalent to a semi-wet type.
[0010]
[Means for Solving the Problems]
The briquette-like baking repair material of the present invention is one or more selected from refractory aggregate and phenol resin powder, coal-based pitch powder, and petroleum-based pitch powder that are burned and carbonized hot to form a carbon bond. A hot binder (hereinafter, hot binder), one or more baking assistants (hereinafter, baking assistants) selected from p-alkylphenols, lactams, bisphenols, diphenyls, diphenylamines, and the heat. It contains a wax having a melting point lower than that of the intermediate binder (hereinafter referred to as wax).
[0011]
The volume per briquette is 5 × 10 ^-6 ~ 1200 × 10 ^-6 m ^Three It is the range of these.
[0012]
The amount of baking aid added is 5 x 10 per briquette. ^-6 ~ 300 × 10 ^-6 m ^Three In the range, the outer shell is 0.2 to 5% by weight.
[0013]
The amount of baking aid added is 300 x 10 per briquette. ^-6 ~ 1200 × 10 ^-6 m ^Three In the range of 5 to 8% by weight, it is characterized by the outer covering.
[0014]
Either a baking aid and a wax are used as molding binders, or a baking repair material in which wax is used alone as a molding binder to form a briquette, and the amount of molding binder added to the baking repair material is determined by molding. It is characterized in that it is 2.5 to 12 parts by weight with respect to 100 parts by weight of the briquette-like baking repair material excluding the binder.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
As a means for suppressing the initial smoke at the time of hot charging, which is the first problem, a molded material having a property that a baking material composed of a powdery refractory aggregate and a hot binder is solid at room temperature and is melted by heating. It is effective to form a briquette with a binder for use. However, a baking material simply molded into a briquette form has a problem that a delay in curing time occurs because it takes time until the molding binder is melted when hot. Therefore, the second problem is to suppress the delay in curing time of the baking repair material molded into a briquette shape.
[0016]
The inventors of the present invention include a baking aid and a wax in a refractory aggregate and a hot binder, and when molded into a briquette form to be a baking material, it is possible to suppress both the initial smoke generation and the delay in the curing time at the time of hot charging. The present invention has been found and the present invention has been made.
[0017]
The baking repair material of the present invention is basically composed of a refractory aggregate whose particle size is adjusted, a hot binder having a melting point of 300 ° C. or less, and an appropriate amount of a baking aid, and if necessary, such as a metal powder. Warm powdered baking material with various additives added, use wax that melts by heating as molding binder, or use baking assistant and wax as molding binder, and mold at above melting point Briquette baking obtained by melting the binder, adding and mixing, molding, or mixing the powder of the binder for molding in advance with the powdered baking material before heating, then heating and kneading it above its melting point and molding It is a repair material.
[0018]
The feature of the present invention is that the wax is solid at room temperature and melts by heating, or by using the baking aid and the wax as a molding binder, there is no dust generation when the material is added hot, immediately after the addition. The amount of smoking is greatly suppressed, and the addition of a baking aid in an amount corresponding to the briquette size to be produced can prevent the curing time from being delayed and can greatly improve the working environment.
[0019]
The present invention relates to a briquette-like baking repair material, which is characterized by the simultaneous use of a baking aid and wax. Details are described below.
[0020]
As the base refractory material, it is possible to use a known refractory material supplied as a natural or artificial product, regardless of whether it is acidic, neutral or basic as a refractory aggregate, either alone or in combination of two or more. it can. Any particle size can be used as long as it is a known particle size range that can be used for ordinary dry-type baking repair materials. For example, the content of fine powder of 0.3 mm or less is adjusted to 10 to 60% by weight.
[0021]
As a hot binder for forming a carbon bond hot and curing and adhering the baking material, one or more of phenol resin powder, petroleum pitch powder and coal pitch powder can be used. In order to shorten the curing time, it is desirable that the melting point is 100 ° C to 300 ° C, preferably 100 ° C to 250 ° C. The hot binder is 5 to 40 parts by weight, preferably 10 to 30 parts by weight with respect to 100 parts by weight of the refractory aggregate, and if it is less than 5 parts by weight, a sufficient carbon bond is not formed and the construction is inferior in strength and adhesiveness. If the amount exceeds 40 parts by weight, the construction body has a large apparent porosity, and the slag resistance is poor.
[0022]
The baking aids p-alkylphenols, lactams, bisphenols, diphenyl, and diphenylamine are solid at room temperature and become a low-viscosity liquid at temperatures above the melting point, as waxes described later. Furthermore, the melted liquid is highly compatible with the hot binder and has the effect of promoting the combustion and carbonization by melting with each other hot.
[0023]
p-alkylphenols have the general formula
[0024]
[Chemical 1]

[0025]
(Where n is an integer of 2 or more)
The melting point is 44-100 ° C, preferably 60-84 ° C. The p-alkylphenol is industrially obtained by reacting an ethylene hydrocarbon with phenol in the presence of aluminum chloride, sulfuric acid, hydrofluoric acid, silicon fluoride, etc., and those shown in Table 1 below. Illustrated.
[0026]
[Table 1]

[0027]
As bisphenol, general formula
HO-C ₆ H _Four -C (R) (R ')-C ₆ H _Four -OH
(Wherein R and R ′ are hydrogen and an alkyl group, which may be the same or different). Specific examples include bisphenol A (melting point: 155 to 157 ° C.) in which R and R ′ are both methyl groups, and bisphenol F and the like in which R and R ′ are both hydrogen.
[0028]
Of the lactams, ε-caprolactam is effective in improving the burning and spreading properties of the baking material, and is also used in powdered baking materials. In order to prevent hardening delay due to briquetting of the baking material, addition of ε-caprolactam (mp 69 ° C.) is desirable. Other examples include diphenyl (mp 69 ° C.) and diphenylamine (mp 52 ° C.).
[0029]
It is good to use what is marketed as a powder form as p-alkylphenols, lactams, bisphenol, diphenyl, and diphenylamines that are baking aids.
[0030]
Next, it is mentioned that the wax is solid at room temperature and becomes a liquid with a very low viscosity when the temperature is higher than the melting point. It acts as a binder for forming a pricket, and has an excellent characteristic such as promoting the spreadability and adhesion of the baking material above the melting point. The waxes are classified into natural waxes and synthetic waxes, and are classified into various types such as animal and plant systems, mineral systems, and petroleum systems, and various commercially available products can be used. The wax has a melting point lower than that of the hot binder.
[0031]
About the lower limit of melting | fusing point in the wax which can be used, what is necessary is just to be higher than the atmospheric temperature which the briquette baking material manufactured contacts in storage. For example, a baking material for a converter may be 40 to 50 ° C. during on-site storage in the summer, so it may be 50 ° C. or higher, and the above-mentioned hot binder has a melting point of 100 to 300 ° C. Examples thereof include paraffin wax (mp 53 ° C.), montan wax (mp 85 ° C.), and the like.
[0032]
The wax is solid at room temperature, but a powdery one is also commercially available and can be used as appropriate. When the wax is dissolved in the heated baking material and added and kneaded, either solid or powder can be used. In addition, when a wax is previously mixed with a baking powder and then heated and kneaded, a powdery wax is preferably used. The finer the powder, the shorter the kneading time.
[0033]
As a feature of the briquette-like baking repair material of the present invention using wax or the wax and a baking aid as a molding binder, the molding binder in the material is first melted at the time of hot charging, and then the phenol resin powder It is mentioned that an initial smoke suppression effect can be obtained by igniting and melting a hot binder such as coal-based pitch. That is, the difference in the melting time between the molding binder and the hot binder makes it possible to suppress the initial smoke, but it has been found that the volume per briquette affects the suppression of the initial smoke. The volume per briquette suitable for smoke control is 5 x 10 ^-6 ~ 1200 × 10 ^-6 m ^Three It was found to be good. In addition, the shape of the briquette is not particularly limited and may be spherical, prismatic, almond, cylindrical, or the like.
[0034]
The volume per briquette is 5 × 10 ^-6 m ^Three If it is less than 1, the heat is instantaneously transmitted to the inside of the briquette, so that the molding binder and the hot binder are melted almost simultaneously, and it is difficult to obtain the effect of suppressing the initial smoke generation. -On the other hand, the volume per briquette is 1200 x 10 ^-6 m ^Three If it is larger, it takes time for heat to be transferred to the inside of the briquette, and although an initial smoke suppression effect is obtained, the curing time of the material is delayed, which may hinder the operation.
[0035]
In the briquette-like baking repair material of the present invention, by using a baking aid and a wax at the same time, the hot fluidity of the material is improved as compared with the case where only one of them is used, and a wide range can be obtained in a short time. Baking is possible, but in particular, the baking aid is excellent in compatibility with the hot binder and also has excellent flammability compared to wax, so that it is possible to prevent the curing delay phenomenon due to briquetting. In particular, the amount of baking aid is important.
[0036]
One or more baking aids selected from p-alkylphenols, lactams, bisphenols, diphenyls, diphenylamines are more flammable than hot waxes, so if the briquette size is large, the repair time While the effect of preventing the delay can be obtained, when the briquette size is small, heat is instantaneously transmitted to the inside of the briquette.
[0037]
For this reason, it is good to change the optimal addition amount of the baking aid depending on the volume per briquette to be manufactured. The volume per briquette is 5 × 10 ^-6 ~ 300 × 10 ^-6 m ^Three In this range, the addition amount of the baking aid is suitably 0.2 to 5% by weight based on the total amount of the refractory aggregate and the hot binder. Also, the volume per briquette is 300 × 10 ^-6 ~ 1200 × 10 ^-6 m ^Three In this range, the addition amount of the baking aid is preferably 5 to 8% by weight based on the total amount of the refractory aggregate and the hot binder. Originally, a baking aid is added to the baking repair material for the purpose of improving spreadability, improving adhesion, and promoting carbonization as described in the above-mentioned baking auxiliary agent, but avoids hardening delay due to briquetting. Therefore, in the briquette-like baking repair material according to the present invention, it is necessary to set the addition amount of the baking aid within the above range.
[0038]
Further, when the wax alone is used as the molding binder, the amount of the wax added is preferably 2.5 to 12 parts by weight with respect to 100 parts by weight of the briquette-like baking repair material excluding the wax. When the added amount of the wax is more than 12 parts by weight, the porosity as the construction body increases and the strength is lowered. In addition, when the baking aid is used as a molding binder, the amount of wax added is the amount obtained by subtracting the amount of the baking aid functioning as a molding binder from the amount of addition when the wax is used alone. However, it is preferable that at least 1 part by weight of the briquette-like baking repair material excluding the wax is used as a wax component to increase the strength of the molded body. It can also be excellent in moldability.
[0039]
If the kneading temperature is higher than the melting temperature of the baking aid, the liquid baking aid functions as a molding binder, so the amount of wax added can be reduced by the amount of baking aid added. An increase in the porosity of the body can be suppressed. In particular, when the briquette size is increased, it is necessary to increase the addition amount of the baking aid, so that kneading at a temperature equal to or higher than the melting temperature of the baking aid is effective in preventing deterioration in durability.
[0040]
Meanwhile, 300 × 10 ^-6 m ^Three In the case of manufacturing briquettes with the following sizes, since the addition amount of the baking aid may be small, the baking aid may be mixed in the material as a powder, and the wax may be used alone as a molding binder. Therefore, when manufacturing a briquette with a small size, it is possible to lower the kneading temperature by using a wax having a melting point lower than that of the baking aid.
[0041]
In addition, it is also possible to add metal powder to the briquette-like baking repair material of the present invention. Al powder is suitable as the metal powder. The Al powder has a high calorific value due to oxidation and is effective in promoting hardening. ₂ O _Three Has high heat resistance. In particular, when MgO is blended in the refractory aggregate, further improvement in durability can be expected by generating spinel by reaction with MgO. As addition amount, the range of 1-10 weight part is good with respect to 100 weight part of refractory aggregates.
[0042]
Next, a method for molding the briquette-like baking repair material of the present invention will be described.
[0043]
The briquette-like baking repair material of the present invention comprises a refractory aggregate, a hot binder, a baking aid, a wax, and the like. If the melting point of the baking aid is larger than the melting point of the wax, the kneading temperature is set to the baking aid. A wax having a melting point below the melting point may be kneaded as a molding binder, thereby lowering the kneading temperature. Also, the baking aid can be made to function as a molding binder together with the wax. In that case, the powder is composed of a refractory aggregate and a hot binder after being heated and melted at a temperature higher than the melting temperature of both. It is better to add and knead to the shaped material, and after adding the wax and baking aid together in powder form into the powder material consisting of refractory aggregate and hot binder, the melting temperature of both wax and baking aid Heat kneading may be performed at the above temperature.
[0044]
In order to mold the kneaded material, any of a metal frame molding method, an extrusion molding method, a pelletizing method, a CIP molding method, etc. can be used. By using a pressure-forming type briquette machine, briquetting is preferably performed continuously, and productivity is improved. When molding using a briquette machine, depending on the binder used, only a low molded body strength can be obtained, and the molded body may collapse with a slight impact, or it may not be molded into a predetermined shape due to the surface of the mold roll. In some cases, a high-strength molded body can be produced by containing a wax. Furthermore, the characteristic of the wax as a lubricant has the advantage that the surface of the material on the mold roll can be completely prevented. Therefore, it can be said that the briquette-like baking repair material of the present invention is optimal for continuous molding by a mold roll. There are various types of mold rolls, and the shape and dimensions of the briquette can be changed. In addition, since the wax and baking aid used in the present invention become a low-viscosity liquid by heating above their melting points, the baking powder can be wetted with a small addition amount compared to coal-based tar and the like. .
[0045]
The amount of the binder for molding in the briquette-like baking repair material of the present invention, including the case where it is molded into a briquette shape with a mold roll, is the wax alone or the total amount of the baking aid and the wax. 2.5 to 12 parts by weight, preferably 3 to 10 parts by weight, is desirable with respect to 100 parts by weight of the briquette-like baking repair material. If the addition amount is less than 2.5 parts by weight, sufficient strength of the molded product cannot be obtained, and there is a risk that the briquette collapses due to the step of bagging the flexible container or the like and a slight impact. Moreover, when the addition amount exceeds 12 parts by weight, the volatile content during hot application increases, so that the construction body structure becomes porous, and the durability may be reduced.
[0046]
The briquette-like baking repair material produced in the present invention is preferably molded into a shape that can quickly move to the repair site when put into a converter or the like. Although it is most desirable to form it into a spherical shape, rolling can be imparted even if it is formed into a prismatic shape, an almond shape, a cylindrical shape, or the like.
[0047]
Hereinafter, examples and comparative examples will be shown, and the briquette baking material of the present invention will be specifically described. However, the present invention is not limited to these examples and descriptions.
[0048]
【Example】
Table 2, Table 3, and Table 4 show the results of the respective blends (% by weight) in Examples and Comparative Examples and the test method described later.
[0049]
Examples 1 to 7 according to the present invention use waxes having different melting points, and the volume per one molded using p-octylphenol as a baking aid is 5 × 10. ^-6 ~ 300 × 10 ^-6 m ^Three The briquette samples of Examples 8 to 14 have a volume of 300 x 10 per piece. ^-6 ~ 1200 × 10 ^-6 m ^Three This is a briquette sample molded using various baking aids. Comparative Example 1 has a volume per briquette of 5 × 10 ^-6 m ^Three Less than, it is a sample which does not add a baking aid. Comparative Example 2 is a briquette sample molded using anhydrous tar as a molding binder. Further, Comparative Examples 3 to 5 show conventional dry type, semi-wet type, and semi-solid type that are not briquetted. In Comparative Example 6, the volume per piece is 300 × 10 ^-6 ~ 1000 × 10 ^-6 m ^Three In this range, the sample does not contain a baking aid.
[0050]
The molding methods of Examples 1 to 7 will be described with reference to Example 1. As fireproof aggregate, 85 parts by weight of MgO powder (particle size of 0.3 mm or less is 30% by weight) and coal tar pitch powder (mp 110 ° C.) ) A baking material consisting of 15 parts by weight and 0.5 parts by weight of p-octylphenol (mp 84 ° C.) was heated to 60 ° C., the same as the molding temperature, and then paraffin wax (mp 53 ° C.) 3 A part by weight was dissolved and mixed and kneaded. The molding device uses a hydraulic hand press, the molding temperature is 60 ° C., the molding pressure is 50 Mpa, and the cylindrical briquette with a diameter of 30 mm (volume per piece 33.5 × 10 ^-6 m ^Three ). In Examples 2-7, it is the same as that of Example 1 except having changed the addition amount, molding temperature, and volume of each component as shown in Table 2.
[0051]
Further, in the molding methods of Examples 8 to 15, as explained in Example 8, 85 parts by weight of MgO powder (particle size of 0.3 mm or less is 30% by weight) and coal tar pitch powder (mp .110 ° C.) 15 parts by weight of the baking material was heated to 95 ° C., the same as the molding temperature, and then 2 parts by weight of paraffin wax (mp 53 ° C.) and p-octylphenol (mp 84 ° C.). 6 parts by weight were dissolved and mixed and kneaded. The molding apparatus uses a hydraulic hand press, the molding temperature is 95 ° C., the molding pressure is 50 Mpa, and the size of the mold is changed to change a cylindrical briquette with a diameter of 60 mm (volume per volume: 563.6 × 10 6 ^-6 m ^Three ). Examples 9 to 15 are the same as Example 8 except that the addition amount of each component, the molding temperature, and the volume of the sample are changed as shown in Table 2.
[0052]
The amount of the binder for molding in the baking repair material is 2.99 parts by weight in Example 1 and 6 in Example 2 with respect to 100 parts by weight of the briquette baking repair material excluding the molding binder. .97 parts by weight, 7.5 parts by weight in Example 3, 10.5 parts by weight in Example 4, 6.8 parts by weight in Example 5, 6.97 in Example 6 Parts by weight, 7.5 parts by weight in Example 7, 8.0 parts by weight in Example 8, 8.0 parts by weight in Example 9, 8.0 parts by weight in Example 10 In Example 11, 7.55 parts by weight, in Example 12, 8.0 parts by weight, in Example 13, 8.0 parts by weight, in Example 14, 8.0 parts by weight, In Example 15, 10.0 parts by weight, in Comparative Example 1 Is 7.0 parts by weight, in Comparative Example 2 is 8.5 parts by weight.
[0053]
Next, a method for testing various baking materials will be described.
[0054]
First, the strength of the briquette-like baked repair material is the load when a load is applied and fracture occurs (kgf / cm ² ) And 10 kgf / cm ² When exceeding 5 is considered “extremely strong”, 5-10 kgf / cm ² In the case of “strong”, 5 kgf / cm ² The case of was set to “medium”. As for the change over time, the sample was put in a plastic bag and allowed to stand at 25 ° C. for 1 week, and the strength of the molded body was measured in the same manner. The case was defined as “strength reduction”.
[0055]
The seizure characteristics were measured by a development test as shown in FIG. 1 and an adhesion test as shown in FIG. 1 to 3, the sample 7 is illustrated in a spherical shape, but the shape of the sample is a columnar shape.
[0056]
FIG. 1A is a schematic cross-sectional view of a box-type heating furnace used for a deployment test, in which 1 is a box-type heating furnace, 2 is an upper lid, 3 is a burner, 4a is a plate portion, 5 is a plate pedestal, 6 is 0.1m in area ² Plate. FIG. 1B is an enlarged view of the plate portion 4a, and 7 indicates a sample. FIG.1 (c) is a figure which shows the state which the sample melt | dissolved-develop | hardened.
[0057]
As shown in FIG. 1, the deployment test starts with an area of 0.1 m. ² The ceramic plate is heated in advance in a box furnace, the upper lid of the furnace is opened, and when the plate surface temperature is 1000 ° C., 800 g of a sample is put on the plate. Since the briquette sample cannot be accurately adjusted to 800 g, the briquette sample was weighed within a range not exceeding 800 g, and then the collapsed briquette sample was added to make fine adjustments to 800 g.
[0058]
After hardening the sample, the sample was quickly taken out together with the plate, and the diameter of the developed sample was measured with a caliper to make it developable. Further, the presence or absence of warpage around the sample was visually confirmed, and the difficulty of peeling and the material strength when the sample was peeled off from the plate surface using an iron spatula were determined. Further, the material structure was judged by visual observation, and a material having no void was determined as good. Moreover, the apparent porosity was measured about the collect | recovered sample piece.
[0059]
FIG. 2A is a schematic cross-sectional view of a box-type heating furnace used for the adhesion test of the samples prepared in Examples 1 to 7 and Comparative Examples 1 to 5, in which 1 is a box-type heating furnace, 2 is Upper lid, 3 is a burner, 4b is a plate portion, 5 is a plate holder, 8 is an area of 0.01 m ² Plate. FIG. 2B is an enlarged view of the plate portion 4b, and 9 indicates an iron cylindrical metal frame (φ70 mm). FIG. 2 (c) shows a state when 150 g of the sample 10 is put on the plate 8. FIG. 2D shows a state in which the shear strength is measured after the sample has been melted and cured.
[0060]
As shown in FIG. 2, the adhesion test starts with an area of 0.01 m. ² The ceramic plate is heated in advance in a box furnace, the furnace lid is opened, and when the surface temperature of the plate is 1000 ° C, an iron cylindrical metal frame is quickly placed on the plate, and 150 g of the sample is placed in the metal frame. (Volume about 70 × 10 ^-6 m ^Three )throw into. The method for collecting 150 g is the same as in the development test.
[0061]
The time from melting to curing of the sample was measured. At this time, the presence or absence of dust generation at the time of material addition was determined visually. Further, the change in the amount of smoke generated 10 seconds after the material was added, 1 minute later, and 6 minutes later was visually measured. Note that the smoke generation amount was 100% when the maximum smoke was generated, and 50% was 50% of the maximum smoke. In addition, the sample was quickly taken out together with the plate and the metal frame after curing, the shear strength of the plate and the metal frame was measured, the shear adhesive strength (MPa) was determined, and the anti-cracking property was evaluated.
[0062]
In the above baking test, each hot characteristic of developability, peel resistance, material strength, curing time, and adhesive strength was evaluated using the judgment symbols shown in Table 5 below. The workability and durability in the actual machine are compared by comprehensively considering each hot characteristic.
[0063]
The weight per briquette is 150g (volume is about 70x10 ^-6 m ^Three The curing time for samples exceeding) was measured by the method shown in FIG. 3 because the curing time measurement performed in FIG. 2 cannot be performed.
[0064]
FIGS. 3A to 3C are schematic cross-sectional views of the box-type heating furnace used for the adhesion test of the samples prepared in Examples 8 to 15 and Comparative Example 6. FIG. In the figure, 1 is a box-type heating furnace, 2 is an upper lid, 3 is a burner, 4b is a plate portion, 5 is a plate holder, and 8 is an area of 0.1 m. ² Plate. FIG. 3B is an enlarged view of the plate portion 4b, and 9 shows an iron cylindrical metal frame (φ150 mm). FIG. 3C shows a state when the sample 10 is put on the plate 8.
[0065]
Area 0.1m ² The ceramic plate is heated in advance in a box furnace, the top lid of the furnace is opened, and when the surface temperature of the plate is 1000 ° C, an iron cylindrical metal frame (φ150mm) is quickly placed on the plate and placed in the metal frame. Insert one briquette sample. The time from melting to curing of the sample was compared with a powder sample before molding without adding a baking aid (equivalent to a briquette sample).
[0066]
The powder sample for comparison compared with Example 8 is 85 parts by weight of MgO powder (particle size 0.3 mm or less is 30% by weight) and 15 parts by weight of coal tar pitch powder (mp 110 ° C.) as the refractory aggregate. What was made equal to the briquette sample of Example 8 was obtained by heating a baking material consisting of 5 parts to 95 ° C., and then dissolving and mixing and kneading 2 parts by weight of paraffin wax (mp 53 ° C.) Each was compared by the adhesion test shown in FIG. 3, and the relative curing time of the sample according to Example 8 was measured. The presence or absence of dust generation and the relative amount of smoke were measured visually as in FIG. The same applies to Examples 9 to 15 and Comparative Example 6.
[0067]
[Table 2]

[0068]
[Table 3]

[0069]
[Table 4]

[0070]
[Table 5]

[0071]
From Examples 1 to 7 shown in Table 3, briquette samples molded using paraffin wax and montan wax having different melting points as molding binders have sufficient molded body strength within a range of 2.5 to 12% by weight. Can be confirmed. Furthermore, it can be seen that the briquette product does not change with time even after being left for one week, and is excellent in storage property.
[0072]
In the adhesion test, there was no delay in curing time, and it was 5 minutes or less in all samples. The peel resistance in the development test is strong, and in particular, Example 5 to which 3% by weight of p-octylphenol was added shows very strong peel resistance. In Example 6 to which Al powder was added, it can be seen that excellent material strength is exhibited. There is no dust generation and the effect of briquetting is confirmed.
[0073]
Regarding the transition of the amount of smoke generated in the adhesion test, it can be seen that the briquette product molded with wax completely prevents smoke generation immediately after the material is charged. As the wax melts due to heat, it gradually ignites hot binders such as coal tar pitch, and reaches a peak of smoke after 2 to 4 minutes, but then the amount of smoke decreases immediately and 5 Smoke is almost gone in ~ 6 minutes. In Example 7, the volume per briquette was 8.2 × 10. ^-6 m ^Three (19g), and it can be seen that the curing time is shortened.
[0074]
In Comparative Example 1, the volume per briquette is 4.2 × 10. ^-6 m ^Three (10 g), and no baking aid was added, but a large amount of smoke was already generated 10 seconds after the addition, and the spreadability was lowered and the curing time was delayed. Comparative Example 2 was a blend in which anhydrous tar was briquetted as a molding binder, and had a certain degree of strength immediately after molding, but it became brittle when left for one week. Comparative Examples 3 and 4 are dry and semi-wet types that are currently used in various places and are excellent in developability and adhesiveness. In the dry type, a large amount of dust is generated at the time of hot charging, and immediately after the charging. Smoke violently. In addition, although the semi-wet type generated a small amount of dust, it smoked violently immediately after the hot addition as in the dry type. Comparative Example 5 is a plastic semi-solid type kneaded with anhydrous tar, but cavities were generated in the vicinity of the surface of the construction body, and smoke generation continued even 6 minutes after the material was added.
[0075]
As shown in Table 5, the volume per briquette is about 70 × 10 ^-6 m ^Three As a result of measuring the presence or absence of dust generation and the transition of smoke generation for samples exceeding (150 g), 63.6% by weight of p-octylphenol was added and 523.6 × 10 6 was added. ^-6 m ^Three Example 8 molded to (1200 g) and 76.0% by weight of p-octylphenol were added to 846.0 × 10. ^-6 m ^Three In Example 9 molded to (2000 g), the effect of suppressing intense smoke generation at the initial stage of charging can be confirmed. Similarly, in Examples 10 to 12 using a baking aid other than p-octylphenol, the effect of suppressing intense smoke generation at the initial stage of charging can be confirmed. In these Examples 8-12, since the volume of one briquette is large and the weight exceeds 1 kg, the time until the end of smoke generation becomes longer, but the curing time with the powder sample before molding without adding a baking aid. The relative curing time (comparative powder sample = 100) showing the comparison of the above can confirm the effect of suppressing the delay of the curing time.
[0076]
Further, the amount of p-octylphenol added is 4% by weight, and the volume per briquette is 523.6 × 10 6. ^-6 m ^Three And 846.0 0 × 10 ^-6 m ^Three In Examples 13 and 14, there was a slight delay in the curing time, but smoke generation immediately after hot addition was completely prevented. In Example 15, the volume per briquette is 1000 × 10 ^-6 m ^Three As in Examples 13 and 14, there is a slight delay in the curing time, but smoke generation immediately after hot addition is completely prevented. Moreover, compared with Examples 8-15, the comparative example 6 which shape | molded using only a wax, without adding a baking adjuvant, resulted in the hardening time becoming long significantly.
[0077]
【The invention's effect】
The briquette baking repair material of the present invention contains an appropriate amount of baking aid in the briquette baking repair material, and uses a wax that is solid at room temperature and melts by heating, or the wax and baking aid as a molding binder. By forming into briquette, it is possible to prevent dusting and smoke generation at the time of charging without impairing the hot characteristics of the conventional powdered baking material, and the working environment can be greatly improved.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a test furnace and a test method for a development test in seizure characteristics.
FIG. 2 is a schematic diagram of a test furnace and a test method for an adhesion test in a seizure characteristic.
FIG. 3 is a schematic diagram of a test furnace and a test method in a baking test of a sample having a weight of more than 150 g per briquette.
[Explanation of symbols]
1 is a box-type furnace, 2 is an upper lid, 3 is a burner, 4a and 4b are plate sections, 5 is a plate support, and 6 is an area of 0.1 m. ² Plate, 7 is sample, 8 is area 0.01m ² , 9 is an iron cylindrical metal frame, and 10 is a sample.

Claims (5)

Refractory aggregates, one or more hot binders selected from phenol resin powder, coal-based pitch powder, petroleum-based pitch powder that are burned and carbonized hot to form carbon bonds, and p-alkylphenols A briquette-like baking repair material comprising one or more baking assistants selected from lactams, bisphenols, diphenyls, diphenylamines, and a wax having a melting point lower than that of the hot binder. The briquette baking repair material according to claim 1, wherein the volume per briquette is in the range of 5 × 10 ^{−6 to} 1200 × 10 ⁻⁶ m ³ . When the addition amount of the baking aid is in the range of 5 × 10 ^{−6 to} 300 × 10 ⁻⁶ m ³ per briquette, the amount of the baking aid is about 0 with respect to the total amount of the refractory aggregate and the hot binder. The briquette baking repair material according to claim 2, wherein the content is 2 to 5% by weight. When the volume of the baking aid is in the range of 300 × 10 ^{−6 to} 1200 × 10 ⁻⁶ m ³ per briquette, it is 5 to 5 on the basis of the total amount of the refractory aggregate and the hot binder. The briquette baking repair material according to claim 2, characterized in that it is 8% by weight. A baking repair material in which both a baking aid and a wax are used as a molding binder, or a wax alone is molded into a briquette as a molding binder, and the amount of molding binder added to the baking repair material is The briquette baking repair material according to any one of claims 1 to 4, wherein the briquette baking repair material excluding a binder is used in an amount of 2.5 to 12 parts by weight with respect to 100 parts by weight. .

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