简介:Thispaperdescribesthebenefits,technicaldifficultiesanddisadvantagesofthecurrentheavyreductionsolutionsforplateproduction.Forupdatedplatemills,thispapergivesabetterideafortheheavyreductioncontrolintherollingprocess.Thatistokeepthereductionamountconstantinthefront-endandback-endsectionsoftheplateandtoadopttaperedrollingwithvariablereductioninthemiddlesectionoftheplate.Thissolution(alreadyappliedforapatent)cannotonlyfullyutilizethecapacityofthemillmotors,butalsopreventdifficultiesinplatebitingcausedbytheconventionalheavyreductionsolutionswithexcessivedraft.Thistechnicalsolutionhasbeenimplementedatthe5mplatemillplantofBaosteel,andindustrialtestshaveprovedthefeasibilityofit.Thispaperpresentsandanalyzestheindustrialtestdataandprovesthatthetaperedheavyreductiontechnologycanreducethenumberofrollingpasses.Inaddition,thispaperlooksforwardtothefutureresearchinthisarea.
简介:Sometimesmaindrivermotors’torqueexceedsthemaximumlimitinBaosteel’s5mheavyplatemill.Experienceshowedthattorqueoverloadedoccurredincasesofsomespecialrollingsequenceandspecialrollingplatedimension.Mostoftheoverloadedoccurredonlyinstantaneousatsometimepointduringtherollingpass,whichespeciallyeasilyhappenedatthebiteandmotoraccelerationtimeafterthebite.Thispaperanalyzestheimpactfactorsformotortorqueoverloadandcarefullystudiesthekeydetailsofthemillrollingspeedcontrol.Thesolutiontoimprovethespeedcontrolwasgivenatthepreconditionofkeepingproductionyield.Theimplementationofthesolutionsignificantlyreducedtheoccurrenceoftorqueoverloadedtimes.
简介:TheSteckelmill,alongestablishedsolutionfortheeconomicalproductionofrelativelysmallvolumesofhotrolledstrip,hasbeenrejuvenatedinrecentyearsbyarangeofnewapplications,boostedbytheneedofimprovingtheenergeticefficiencyoftherollingprocess.ThetraditionaladvantagesoftheSteckelmillintermsofflexibilityandreducedcapitalandoperationalcostsarenowenhancedbytechnologicaldevelopmentsthathavesignificantlyexpandeditsapplicationrangeintothecombinedproductionofstripandplateandimprovedtheproductquality.Theincreasedawarenessofthenecessityofasustainablegrowthinthesteelindustryhasstimulatedthedevelopmentofprocesssolutionswithanimprovedefficiencyintheuseofnaturalresources,lowercarbonemissionsandincreasedyield.ModernSteckelmillsareanadequateresponsetothetrendtowardslowenergystripandplateproduction,inparticularintheirplate-Steckelmillvariant.SiemensVAIhaveplayedakeyroleintheinnovationandtransformationoftheSteckelmillconcept,withanumberofrecentinstallations,presentedinthispaperfromthepointofviewoftheircontributiontothedevelopmentofgreenersteelrollingtechnologies.
简介:HeavyplaterollingprocessingineverysinglepasswassimulatedbythemethodofFEM.Distributionoftheinflowstrainonthespecifiedpathandrelatedparameters(platethicknessH,passreductiondH,rollingspeedV)inthethicknessdirectionoftheplatecenterwerestudied.TheresultsshowthattheplatethicknessHandpassreductiondHhavesignificanteffectsontheinflowstrainonthespecifiedpath,whiletherollingspeedpresentslittleeffect.Therelationshipsbetweenthestrain(PEEQ)andtheplatethickness(H)/passreduction(dH)werealsoestablishedbasedonthesimulationresults.
简介:TheNo.3slabcaster,whichmainlyprovidesslabstothe5000mmplatemillatBaosteel,wasputintoproductioninDecember,2004.Thesizeofthebiggestslabproducedbythiscasteris2300mminwidthand300mminthickness.Thedesignedoutputofthecasteris2.3Mt/a.Slabsurfacelongitudinalcrackdefects,whichwererelatedtotheheatfluxofthemold,frequentlyoccurredintheearlystageofthestartupofthecaster.Asmildcoolingpowderisbeneficialtotheuniformityoftheshellofinitialslabs,theconcentrationofstressisreduced,andthelongitudinalcrackingonthesurfaceisavoided.Thisstudyevaluatestheperformanceofseveralkindsofpowder,andtheresultsshowthatmoldpowderofhighbasicity,highcrystallizationproportionandlowheatfluxistothebenefitofthereductionofthelongitudinalcracksonthesurfaceandthedefectsofslabs.
简介:Inthispaper,abriefintroductiononclad-rollingheavysteelplatesof90mmand140mmthickispresented.Thesteelplateswerehotrolledby265mmslabsthatarecladdedbydouble135mmcontinuouscastingslabsofQ235steel.Afterhotrolling,interfaceofthecladdingslabscompletelydisappeared,revealinguniformgrainssimilartotherestofthematerials.Ultrasonictestswerecarriedoutonbothsteelplates,demonstratingexcellentresults.Throughthicknesstensiletestswerealsoimplementedonbothsteelplates,resultinginperfectmechanicalpropertiescomplyingwithspecificstandards.Theresultprovesthataminimumreductionrateof1.89isavailableinproducing140mmthicksteelplatewithexcellentthroughthicknessproperties.
简介:ThedimensionvariationofB610EsteelduringthequenchingandtemperingprocesswassimulatedbyABAQUS,thecoefficientofheattransferduringquenchingwasverifiedbytheburiedthermocoupletestandthetrendofthedimensionvariationduringthequenchingprocesswasalsocalculatedbyABAQUS.Itwasshownbythecomparisonofsimulatedresultsandindustriallymeasuredresultsthatonlythesimulationofthicknessandwidthvariationwasaccurate,whilelengthvariationneededfurthersimulation.Besides,thedimensionvariationtrendwasidenticalwiththemeasuredresults.
简介:Recrystallizationtextureofsteelplateisaffectedbysubstitutionsolidsolutionandinterstitialsolidsolution.Thisarticlefinishedtexturetestandstampingtestaboutlowcarbonaluminiumkilledsteel,IFsteel,phosphorusstrengthensteel,Si-Mn-Pstrengthensteel.Itcanbefoundthatallkindsofsteelhassimilarintensity{111}textureinpermanentφ=45°aboutlevel10.Interstitialsolidsolutionsteelhad{101}textureandsubstitutionsolidsolutionsteelhad{112}texture.Basedonrecysstallizationprincipleandstampingtest,theeffectofsolutiononrecrystallizationtextureisdiscussed.Itpointoutthatinterstitialsolidsolutionimpediment{111}textureformingandcausedto{101}textureremainedinsteel.Thephenomenonstrengthenanisotropicpropertyandreductionstampingproperty.Similartosubstitutionsolidsolution,itwouldimpediment{111}texturetoo,but{101}texturechangedto{112}texture.
简介:Controlledcoolingtechnologyisgettingmoreandmoreattentionwiththedevelopmentofthermal-mechanicalcontrolprocess.Inthepastdecade,achievingthegivenfinishcoolingtemperaturewasthesolegoalforthetechnology.However,withtheresearchanddevelopmentofnewsteelssuchassuperhighstrengthsteel,researchershaveinrecentyearsrealizedthedeterminateeffectsthatdifferentcoolingpathshaveonthefinishcoolingtemperatureandpaidmoreattentiontothecontrolofthecoolingrate.Thispaperfocusesonnotonlytheoptimizationofthecontrolledcoolingsystemwithhighprecisionandfastcoolingrate,butalsotheresearchanddevelopmentofthehighstrengthsteelplatewithreducedalloyingcomponent.
简介:Resultspresentedinthisstudycontributetoinvestigationofthemicrostructureandmechanicalpropertiesofthehot-rolledFe16Mn0.6Csteelplates.Thesteelplateshavebeenproducedbybeinghot-rolledattemperaturesrangingfrom1100℃to850℃insevenpassesto97.5%reductioninthicknessandthencooledinafurnaceof650℃.Someplateshavebeenannealedattemperaturesrangingfrom300℃to1100℃for5minto60min,andthenfollowedbywaterquenching.Thereareannealingtwinsinthehot-rolledFe16M...
简介:Aconoscopicholography-based3Dmeasurementsystemforanalyzingthedefectsonthesurfaceofsteelplateswasintroducedinthispaper.Thehardware,whichisautomatedthroughsoftware,performssamplingofthesteelplatesurface.Throughthesoftwareinterface,point-clouddataofthesteelplatesurfaceareobtainedandreconstructedtoforma3Dimageofthesteelplatesurface.Thesoftwareallowsautomaticanalysisofsteelplatesurfacedefectsthroughidentificationofthebulgesanddepressions.Inaddition,thesoftwarecanalsoautomaticallycalculatethedefectinformation,suchasthedeepestpoint,volume,openingarea,openinglength,andsoon,therebydeterminingthedefectsize.Theresultsdeterminedbythis3Dmeasurementsystemwerefoundtobeingoodagreementwiththeactualvalues.
简介:Loadingdistributionforheavyplatemillistofindoptimalcontrolsolutionsunderthegrantedperformanceindicatorsandconstraintsincludingmillcapacityandhypothesisofrollingmodels.Thesolutionsarequitedifferentfordifferentperformanceindicators.Inthearticle,theperformanceindicatorsandsequentialquadraticprogramming(SQPforshortbelow)methodsemployedin5000mmheavyplatemillofBaoSteelarepenetratinglyanalyzed.Generally,theSQPmethodisaneffectiveandfastwaytosolvethenonlinearprogrammingproblemswithsmallormediumscaleconstraints.Earlyin1976,HanputforwardtheSQPmethodforthefirsttimeandPowellmadeitperfectandaccomplishedthealgorithmin1977.Infact,SQPmethodwastoturnanonlinearprogrammingproblemtoaseriesofsubsetofquadraticprogrammingproblems.Inthealgorithm,eachiterationstepistosolveonequadraticprogrammingproblem.Theoptimalsolutionswillbegraduallyapproachedafterquadraticprogrammingproblemsweretotallysolved.Whensolvingthequadraticprogrammingproblem,theactivesetstrategywereemployedwhichturnedtheconstrainedquadraticprogrammingproblemtounconstrainedquadraticprogrammingproblem.Theactivesetstrategymadethewholequadraticprogrammingproblembesolvedbyaleastsquareproblem.Andfinally,thematrixoftheleastsquareproblemwouldbedecomposedbyQmatrixandRmatrix.AfterQmatrixandRmatrixwereobtained,theoptimalsolutionswouldbefinallyfound.Forloadingdistribution,theperformanceindicatorswerecomposedbyplateshapeanddraftofeachpass.Plateshapeisrepresentedbyrollingforcegraduallyreducedpassbypasswithatunablefactor.Themillcapacityisanotherperformanceindicatorrepresentedbydraftofeachpass.Forheavyplatemill,themillcapacityhereisthemotormoment.Forheavydraft,themotorwouldbeoverloadedespeciallyforthefirstseveralpasses;forsmalldraft,themotorwouldbeloadedslightly.Allthesewouldnotbepermittedtohappenwhen
简介:Baosteel's5mheavyplateplantwassuccessfullytestedonMarch1,2005.Sincethen,theHeavyPlatePlantofBaosteel(hereinafterreferredtoas'theplant')hasbeenencouragingitsemployeestostudyandtracetheadvancedheavyplatetechnologies,tryingtofindouttherulesofheavyplateproductionanditsqualitycontrol.TheplanthasgraduallymasteredthismodernheavyplateplantandensuredthatBaosteel'sproductionofheavyplatesgrewyearbyyear,with1.41Mtproductputinstoragein2007.Theplanthasfocusedondevelopingnewtechnologiesandproducts,meanwhileenhancingitscapacity.Ithasproducedaseriesofplateproducts,whichcanbeusedinmanufacturingshiphulls,pipelines,bridges,buildings,boilersandpressurevessels.
简介:ThisstudysystematicallyreviewsandsummarizesrelocationandrevampingprojectofmediumandheavyplaterollingmillinBayiSteel.AfterdetailedanalysiswasmadeonthemaindeficiencyandproblemsoftheoriginalproductionlineofPudongSteel,systematicalintegrationandimprovementfortheprocessandequipmentwerecarriedoutaccordingly.Throughinnovativepracticeofintegration,BaosteelEngineeringhasgreatlyimprovedthetechnicalprocessandequipmentmake-up,aswellasthegradesandqualityoftheproducts.Theoriginalman-operatinglineisredesignedintoanautomaticsystemcontrolledbyLevel2computer,reachingtheadvancedtechnicallevelofhome-mademediumandheavyplateproductionlineinrecentyears.Theprojectisconstructedintwophases;TheoriginalproductmixofPudongSteelismaintainedasmuchaspossibleinPhaseI.After3500mmsinglestandfinishingmillisputintooperation,capacityofhot-rollingmediumandheavyplatereaches650000t/a,withthemaximumthicknessat40mm.Equipmentorfacilitiesarereservedforproductionofpipelinesteelandothergrades.Pipelinesteel,vesselplate,windpowerplateandotherTMCPandheattreatmentproductsareprojectedinPhaseⅡ.After4200mmroughingmillanditsmatchedfacilitiesareputintooperation,capacityofhot-rollingmediumandheavyplatewillreach120000t/a,withthemaximumthicknessat80mm.Throughtheoptimizationofprocessequipmentanditsfunction,therelocatedmediumandheavyplatemillproductionlinehasreachedadvancedlevelamongsimilardomesticmills.Theprominentachievementsoftheprojectaretherevampingofthicknesscontrolsystemofthefinishingmillandthenewlyinstalledshapecontrolsystem.Automationcontrolofthewholelineisrealized.