简介:Lightweightdesignisoneofthedevelopmenttrendsoftheautomobileindustry.AneffectivewaytoachievelightweightautobodiesistouseAHSS(advancedhighstrengthsteel)forthesafetycomponentsofautomobiles.ThisstudyhastakendoorsillreinforcementsmadeofmartensiteAHSSastheobject,andperformedresearchontheAHSSrollformingtechnologiesandprototypedevelopmentoftypicalasymmetricopencomponents.Bymeansoffiniteelementanalysis(FEA)andsimulation,studieshavebeencarriedoutonthespringbackandedgewavedefectsduringAHSSrollforming,andanoptimizedprocessdesignhasbeenachieved.Thegenerationmechanismsofverticalbows,horizontalcambers,twists,pre-punchedholedistortionandcutendflarehavebeenanalyzed,andsolutionstothesedefectshavebeengiven.Inaddition,tesingoftherollformingprocessforAHSShasbeenconductedandtypicalsampleswithrequireddimensionalaccuracyhavebeenmanufactured.Thisstudyhasprovidedtechnicalsupportforthelarge-scaleapplicationofAHSS.
简介:Toaddressthephenomenonofsparkingduringtheedgeinductionheatingprocessinhotstripmills,thispaperusesnumericalsimulationtosystematicallyinvestigatethekeyfactorsinfluencingsparkingandtheireffects.Thedistributionofinducedcurrentdensityinthesteelplateaboverollerconveyortableduringtheheatingprocessiscalculatedandcomparedunderdifferentconditions,includingtherelativepositionsofthesteelplateandinductioncoil,thewidthofthesteelplate,andchangesinload.Theresultsshowthatwhenanarrowsteelplateisheatedorthesteelplateshiftstothesideoftheinductioncoil,sparkingbetweenthesteelplateandrollerconveyorismorelikelytooccur.
简介:Thisarticleistrytoexplainoranalyzethekeytechnologiesofcontrollingthesurfacequalityoflowcarbonsteelascaststripthroughinvestigationofinterfaceheattransferbetweensolidifiedshellandliquidsteel.Theoneofthekeytechnologiesofcontrollingsurfacequalityoflowcarbonsteelascaststripisthroughthecastingrollsurfacetextureinordertoachievethehomogeneoussolidificationonthecastingroll.Anotheristhroughformingathinfilmonthecastingrollsurfaceinordertoachieveabalancebetweenrapidsolidificationandhomogeneoussolidification.Thisfilmformedbetweenthetwinrollandthemoltensteelcanbecontrolledbyadjustingthechemicalcompositionandinclusioninliquidsteelthroughcontrollingtheamountofall[O]andfree[O].
简介:Chinaisanimportantcountryinironandsteelindustry.Powerelectronicsconvertersarewidelyused.Forthecoldrollingmillsofhighspeed,AC-DC-ACconvertersshouldbeused.Inthepaper,thedesignandthecontrolsystemofthelargepowerthree-levelAC-DC-ACconverterwithIGCTsisinvestigated,andaback-to-backlargepowerthree-levelAC-DC-ACconverterwithIGCTshasbeengot.Withaseriesexperiments,theperformanceoftheconverterisexamined.Theexperimentresultindicatestheconverterreachesthedesignrequirementanditshowsexcellentperformance.Theconvertersystemhasbeenputintousesafely.ItisestimatedthattheAC-DC-ACconvertersystemwillbeusedinthedrivesystemsforrollingmillsinthenearfuture.
简介:涟钢长期以来在计划经济体制下形成了“大而全、小而全”状况,与主体配套的辅助、后勤单位几乎全是亏损或靠补贴维持,“冗员多、包袱重、效率低”,已严重制约着企业的生存和发展。因此,从1996年开始建立现代企业制度,1997年实施以“精干主体、分离辅助”为重点的结构性改革,先后将21家辅助后勤单位剥离改制为子公司,构建母子公司体制。通过4年多的改革和完善,由改制前累计亏损7560万元至2000年累计实现盈利3203万元,共计实现扭亏增利10763万元。全面扭亏为盈的已有13家,占子公司总数的62%。大大减轻了主体的负担,提高了企业整体效益,基本改变了主辅同吃钢铁“大锅饭”的局面。