Using Al2O3-MgO castable in large ladle can avoid containation of molten steel from carbon-containing refractories and increas ladle servic life remarkably,The addition of magnesia and fine powder,the effect of grain ...Using Al2O3-MgO castable in large ladle can avoid containation of molten steel from carbon-containing refractories and increas ladle servic life remarkably,The addition of magnesia and fine powder,the effect of grain size on the proper-ties of the castable,especially linear change and structure spalling have been studied,Castable pro-dued for large ladle with small weare rate has got good applicatio result.展开更多
The paper describes the process of producing high quality magnesite-chrome bricks for VOD re-fining furnace,The service life reaches 14 heats,average life 12 heats.The studies show that the wear of the magnesity-chrom...The paper describes the process of producing high quality magnesite-chrome bricks for VOD re-fining furnace,The service life reaches 14 heats,average life 12 heats.The studies show that the wear of the magnesity-chrome bricks is mainly due to chemical corrosion,thermal spalling induced by thermal shock and the corrosion aroused from accumulation of molten materials in transition zone.展开更多
Dolomite refractory products with excellent hydration resistance have been produced by using CeO2-and CeO2/Fe2O3-bearing dolomite clinkers,Their physical properties as well as hydration resistance have been investigat...Dolomite refractory products with excellent hydration resistance have been produced by using CeO2-and CeO2/Fe2O3-bearing dolomite clinkers,Their physical properties as well as hydration resistance have been investigated,The addition of CeO2 has little harmful effect on the high temperature properties of dolomite refractory products such as hot MOR and slag resistance,And the shelf lives of the dolomite refractory products containing CeO2 and CeO2/Fe2O3 additions at the same condition are two times that of the common dolomite refractory produt.The dolomite refractory product containing CeO2/Fe2O3 combination possesses the best hydration resistance,but gives poor slag resistance.展开更多
The application results of semi-rebonded magnesite-chrome bricks at RH lowe vessel of NKK Corporation Keihin Works have been analysed,The results indicate that the main reasons that cause the damage of the refactory b...The application results of semi-rebonded magnesite-chrome bricks at RH lowe vessel of NKK Corporation Keihin Works have been analysed,The results indicate that the main reasons that cause the damage of the refactory brcks include:chemical attack of slage to the semi-rebonded magnesite-chrome bricks;pene-tration of molten stel,slag into the bricks;and therma spalling due to temperature fluctua-tion during steel making operation.The results of multiple effection of these factors lead to alternative action of erosion(chemical attack and penetration)and spalling(thermal spalling and structure peeling) resulting in the damage of the brik ,In order to improve the performance of the bricks ,it is necessary to promote the resistance to erosion and thermal shock resistance as well as to keep the accurate dimensions of the brick,The measures of improvement of resistance to erosion of magne-site-chrome bricks taken by the researches mainly include:lowering the contents of impu-rities in the bricks(mainly including SiO2,CaO,and next Fe2O3 and Al2O3);promoting the extent of direct bond of the brick;forming a large amount of magnesia-chrome composite spinel well-distributed in the bricks through adding a large amount of synthesized materi-als;enhancing the resistance to erosion by adding a little amount of high-effective additives,Improvement of thermal shock resistance of the bricks is mainly through introducing some additive to make a certain amount of mi-cro-cracks occur in the brick so as to obtain an effect of increasing toughnes or through for-mation of second high temperature solid phase in the brick by adopting additive,In addition,it is needed to improve the quality of the brick appearance and ensure accurate dimensions of the brick,The purpose of this paper is to further iprove the service life of the refractory bricks by making use of the improvement mea-sures taken on the basis of the analysis results of the used bricks.展开更多
ZrO2 -containing refractories have been increasingly used for cement rotary kilns. This paper discusses how the properties and performance of ZrO2-containing refractories are improved in terms of chemical attack resis...ZrO2 -containing refractories have been increasingly used for cement rotary kilns. This paper discusses how the properties and performance of ZrO2-containing refractories are improved in terms of chemical attack resistance, thermal shock resistance , thermal conductivity and mechanical stress.展开更多
文摘Using Al2O3-MgO castable in large ladle can avoid containation of molten steel from carbon-containing refractories and increas ladle servic life remarkably,The addition of magnesia and fine powder,the effect of grain size on the proper-ties of the castable,especially linear change and structure spalling have been studied,Castable pro-dued for large ladle with small weare rate has got good applicatio result.
文摘The paper describes the process of producing high quality magnesite-chrome bricks for VOD re-fining furnace,The service life reaches 14 heats,average life 12 heats.The studies show that the wear of the magnesity-chrome bricks is mainly due to chemical corrosion,thermal spalling induced by thermal shock and the corrosion aroused from accumulation of molten materials in transition zone.
文摘Dolomite refractory products with excellent hydration resistance have been produced by using CeO2-and CeO2/Fe2O3-bearing dolomite clinkers,Their physical properties as well as hydration resistance have been investigated,The addition of CeO2 has little harmful effect on the high temperature properties of dolomite refractory products such as hot MOR and slag resistance,And the shelf lives of the dolomite refractory products containing CeO2 and CeO2/Fe2O3 additions at the same condition are two times that of the common dolomite refractory produt.The dolomite refractory product containing CeO2/Fe2O3 combination possesses the best hydration resistance,but gives poor slag resistance.
文摘The application results of semi-rebonded magnesite-chrome bricks at RH lowe vessel of NKK Corporation Keihin Works have been analysed,The results indicate that the main reasons that cause the damage of the refactory brcks include:chemical attack of slage to the semi-rebonded magnesite-chrome bricks;pene-tration of molten stel,slag into the bricks;and therma spalling due to temperature fluctua-tion during steel making operation.The results of multiple effection of these factors lead to alternative action of erosion(chemical attack and penetration)and spalling(thermal spalling and structure peeling) resulting in the damage of the brik ,In order to improve the performance of the bricks ,it is necessary to promote the resistance to erosion and thermal shock resistance as well as to keep the accurate dimensions of the brick,The measures of improvement of resistance to erosion of magne-site-chrome bricks taken by the researches mainly include:lowering the contents of impu-rities in the bricks(mainly including SiO2,CaO,and next Fe2O3 and Al2O3);promoting the extent of direct bond of the brick;forming a large amount of magnesia-chrome composite spinel well-distributed in the bricks through adding a large amount of synthesized materi-als;enhancing the resistance to erosion by adding a little amount of high-effective additives,Improvement of thermal shock resistance of the bricks is mainly through introducing some additive to make a certain amount of mi-cro-cracks occur in the brick so as to obtain an effect of increasing toughnes or through for-mation of second high temperature solid phase in the brick by adopting additive,In addition,it is needed to improve the quality of the brick appearance and ensure accurate dimensions of the brick,The purpose of this paper is to further iprove the service life of the refractory bricks by making use of the improvement mea-sures taken on the basis of the analysis results of the used bricks.
文摘ZrO2 -containing refractories have been increasingly used for cement rotary kilns. This paper discusses how the properties and performance of ZrO2-containing refractories are improved in terms of chemical attack resistance, thermal shock resistance , thermal conductivity and mechanical stress.
