简介:Theapplicationresultsofsemi-rebondedmagnesite-chromebricksatRHlowevesselofNKKCorporationKeihinWorkshavebeenanalysed,Theresultsindicatethatthemainreasonsthatcausethedamageoftherefactorybrcksinclude:chemicalattackofslagetothesemi-rebondedmagnesite-chromebricks;pene-trationofmoltenstel,slagintothebricks;andthermaspallingduetotemperaturefluctua-tionduringsteelmakingoperation.Theresultsofmultipleeffectionofthesefactorsleadtoalternativeactionoferosion(chemicalattackandpenetration)andspalling(thermalspallingandstructurepeeling)resultinginthedamageofthebrik,Inordertoimprovetheperformanceofthebricks,itisnecessarytopromotetheresistancetoerosionandthermalshockresistanceaswellastokeeptheaccuratedimensionsofthebrick,Themeasuresofimprovementofresistancetoerosionofmagne-site-chromebrickstakenbytheresearchesmainlyinclude:loweringthecontentsofimpu-ritiesinthebricks(mainlyincludingSiO2,CaO,andnextFe2O3andAl2O3);promotingtheextentofdirectbondofthebrick;formingalargeamountofmagnesia-chromecompositespinelwell-distributedinthebricksthroughaddingalargeamountofsynthesizedmateri-als;enhancingtheresistancetoerosionbyaddingalittleamountofhigh-effectiveadditives,Improvementofthermalshockresistanceofthebricksismainlythroughintroducingsomeadditivetomakeacertainamountofmi-cro-cracksoccurinthebricksoastoobtainaneffectofincreasingtoughnesorthroughfor-mationofsecondhightemperaturesolidphaseinthebrickbyadoptingadditive,Inaddition,itisneededtoimprovethequalityofthebrickappearanceandensureaccuratedimensionsofthebrick,Thepurposeofthispaperistofurtheriprovetheservicelifeoftherefractorybricksbymakinguseoftheimprovementmea-surestakenonthebasisoftheanalysisresultsoftheusedbricks.
简介:Thenon-burnedcorundumspineluppernozzle,maldeofelectro-fusedcorunndumpowder,highpureelectro-fusedspinelwiththermosettingresinasbinder,addedwithcompoundant-oxdationadditives,hassuperiorHMOR,excellentcorrosionresistanceandsimpleproductionprocess,Theuppernozzlewasusedin90MTladleandtheservicelifewasimprovedby50%to60%
简介:TheapplicationresultsofSemi-rebondedMagnesite-ChromebricksatRHlowervessloftheNKKCorporationKeihinWorkshavebeenanalysed.Theresultsindicatethatthemainreasonsthatcausethedamageoftherefractorybricksincludechemicalat-tackofslagtotheSemi-rebondedMagnesite-Chromebricks;penetrationofmoltensteelandslagnintothebricks;andthermalspallingduetoteperaturefluctuationduringsteelmakingoperation.There-sulitsofmultipleeffectionofthesefactorsleadtoalternativeactionoferosion(chemiclattackandpenetration)andspalling(thermalspallingandstructurepeeling)resultinginthedamageofthebrick,Inordertoimprovetheperformanceofthebricks,itisnecessarytopromotetheresistancetoero-sionandthermalshockresistanceaswellastokeeptheauratedimensionsofthebrick.Themeasurestoimprovetheresistancetoerosionofmagnesite-chromebrickstakenbytheresearchersmainlyin-clude:loweringthecontentsofimpuritiesinthebricks(mainlyincludingSiO2,CaO,andnextFe2O3andAl2O3);promotingtheextentofdirectbondofthebrick;formingalargeamountofmagnesia-chromecompositespinelwell-distributedinthebricksthroughaddingalargeamountofsynthe-sizedmaterials;enhancingtheresistancetoerosionbyaddingalittleamountofhigh-effectiveaddi-tives,Improvementofthermalshockresistanceofthebricksismainlythroughintroducingsomeaddi-tivetomakeacertainamountofmicro-cracksoccur-inginthebricksoastoobtaintheeffectofincreasetoughnessorthroughformationofsecondhightem-perturesolidphseinthebrickbyadoptingaddi-tive,Inddition,itisneededtoimprovethequalityofthebrickappearanceandensureaccuratedimen-sionsofthebrick,Thepurposeofthispaperistodescribethefurtherimprovementoftheservicelifeofrefactorybrickbythemeasurestakenonthebasisofthenalysisresultstotheusedbricks.
简介:Inordertoprolongtheservicelifeofthecoolingzoneoflargescalecokedryquenchingovens,sixkindspossiblerefractoriesforthecoolingzoneoflargescalecokedryquenchingovens:SiCcontainingbrickA,SiCcontainingbrickB,mullite-andalusitebrick,spinelcontainingbrick,zirconiacontainingbrick,corundum-mullitebrickandgradeBmullitebrick,wereanalyzedinproperties.ItisfoundthatthecoolingzoneliningadoptingSiCcontainingbricksormullite-andalusitebrickshasmuchlongerservicelife.Basedonthis,anewtypeofwearresistantbrickwasdeveloped.Thebrickhasacompressivestrengthof135MPa,awearlossof2.10cm~3(onlyaquarterofthatofthegradeBmullitebrick),andahigherbulkdensitythanthegradeBmullitebrick.Theapplicationofthebrickina140t·h~(-1)cokedryquenchingovenshowedthatitperformedbetterthanthegradeBmullitebrick.Thecoolingzoneadoptingthenewbrickshasalowercokedischargingtemperature,whichisbeneficialtotheenhancementofheatrecoveryefficiencyandsteampowergeneration.
简介:UsingAl2O3-MgOcastableinlargeladlecanavoidcontainationofmoltensteelfromcarbon-containingrefractoriesandincreasladleservicliferemarkably,Theadditionofmagnesiaandfinepowder,theeffectofgrainsizeontheproper-tiesofthecastable,especiallylinearchangeandstructurespallinghavebeenstudied,Castablepro-duedforlargeladlewithsmallweareratehasgotgoodapplicatioresult.