GBT 6725-2008 英文版 冷弯型钢标准

12PrefaceModifythisstandardbyEN10219.12006finegraincarbonsteelandcoldformedweldedsteelstructuralhollowsectionsofPart1:Technicaldeliveryconditions,themaindifferencesareasfollows:---Ofsteelgradesandgradesaccordingtothecorrespondingstandardsandgrades;---Sampling,testingmethods,re-inspectionoftherelevantrules,accordingtonationalstandards.ThisstandardreplacesGB/T6725-2002cold-formedsteel.Therevisionofthestandardcontentofthefollowingtechniquesweremodified:---Adjustednormativereferences;---Increaseproductyieldstrengthclassification;---Increasethefine-grainedsteel;---Increasethemechanicalpropertiesoftheproductspecificassessmenttargets.AppendixAofthisstandardfortheinformativeappendix.ThestandardproposedbytheChinaIronandSteelAssociation.ThisstandardisstandardizedbytheNationalSteelTechnicalCommittee.Thedraftingofthisstandard:ShanghaiBaosteelConstructionDesignandResearchInstitute,WuhanIronandSteelGroupHankouRollingMill,SteelPlantCo.,Ltd.,Guangzhou,FoshanCity,ChiofSteelPipeManufacturingCo.,Ltd.,ShanghaiJiayiCold-FormedSteel.Maindraftersofthisstandard:YuMATRIX,Qian,theMayueFeng,Xiu-FangZhang,LiYe,ZhangYongqi,LiJianzhang,ZhangJing.Thisstandardreplacesthepreviouslyissuedstandardis:---GB/T6725-1986,GB/T6725-1992,GB/T6725-2002.1.ScopeThisstandardspecifiesthecontentofcold-formedsteelordering,classificationandcodename,size,shape,weightandtolerance,technicalrequirements,testmethods,inspectionrules,packaging,markingandqualitycertification.Thisstandardappliestocoldrolledorhotrolleddeformedsteelsheetandstripinacontinuousrollerbendingmachineontheproductionofcold-formedsteel.2.ReferenceStandardThetermsofthefollowingdocumentsbythestandardreferenceintheprovisionsofthisstandard.Fordatedreferences,subsequentamendments(excludingcorrections)orrevisionsdonotapplytothisstandard,however,encouragethepartiestoreachanagreementbasedonthisstandardtostudywhetherthelatestversionofthesedocuments.Forundatedreferences,thelatestversionappliestothisstandard.ChemicalcompositionofsteelproductsGB/T222ToleranceGB/T228roomtemperaturetensiletestmethodsformetallicmaterials(GB/T228-2002,eqvISO6892:1998(E))GB/T229metalmaterialsCharpypendulumimpacttestmethod(GB/T229-2007,3ISO148-1:2006,MOD)GB/T232metalbendingtestmethod(GB/T232-1999,eqvISO7438:1985(E))GB/T699qualitycarbonstructuralsteelGB/T700carbonstructuralsteelGB/T714structuralsteelforbridgeGB/T1591high-strengthlow-alloystructuralsteelGB/T2101steelinspection,packaging,markingandqualitycertificationoftheGeneralProvisionsGB/T2975mechanicalpropertiesofsteelandsteelproducts,thelocationandpreparationoftestsamplesStainlesssteelcold-rolledsteelsheetandstripGB/T3280GB/T4171resistingstructuralsteelGB/T6394determinationofaveragegrainsizeofmetalGB/T17505steelandsteelproductsGeneraltechnicaldeliveryrequirements(GB/T17505-1998,eqvISO404:1992)3.ContentsoforderThecontractorordermadeaccordingtothisstandardshallincludethefollowingcontents:A)Standardserialnumber；B）ProductSize；C）Materialgradeandyieldstrengthgrade;D)Deliveredweight（theoreticalweightoractualweight）andlength;E)Specialrequirement.4.ClassificationandCode4.1Accordingtoshape,sectionsteelisclassifiedasround,square,rectangleandotherspecialcoldformedsteelhollowsections.Codesforthemareasfollowing:Roundcoldformedsteelhollowsection,roundtubeisforshort,andthecodeisYSquarecoldformedsteelhollowsection,squaretubeisforshort,andthecodeisFRectanglecoldformedsteelhollowsection,rectangletubeisforshort,andthecodeisJSpecialcoldformedsteelhollowsection,specialtubeisforshort,andthecodeisYIGB/T6725—2008Openingcoldformingsteelsections,oropeningsteelsectionsforshort,accordingtothesectionalshapecodedas:JD(equilateralanglesteel),JB(scaleneanglesteel),CD(equilateralchannelsteel),CB(scalenechannelsteel),CN(channelsectionwithinneredge),CW(channelsectionwithouteredge),Z(Z-steel),ZJ(curledZ-steel).4.2Accordingtoyieldstrengthisclassifiedas235,345,390.5.Size,shape,weightanditspermissibledeviation.4Shallmeettherequirementoftherelevantstandard.6.Technicalrequirements6.1Gradeandchemicalcomposition6.1.1Thegradeandchemicalcomposition(smeltinganalysis)ofcoldformedsteelsectionsshallmeettherequirementsofGB/T699,GB/T700,GB/T1591,GB/T3280andGB/T4171.Coldformedsteelsectionsofothergradesmaybesuppliedaccordingtotherequirementsofpurchaser.6.1.2Accordingtotherequirementofthepurchaser,grade345,390steelsectioncouldbeproducedbyfinegrainsteel.6.1.3ChemicalcompositionpermissibledeviationshallmeetrequirementofGB/T222.6.2ConditionofdeliveryColdformedsteelsectionsshallbedeliveredintheshapeofcold-working.Thespecialrequirementsshallbeagreedbyboththesupplierandthepurchaser.6.3Mechanicalperformance6.3.1Yieldstrength,tensilestrengthandelongationafterfractureshallmeettherequirementoftable1.6.3.2Impacttestshallbeindicatedinthecontractupontherequestfromthepurchaser.6.3.3Forsteelsectionwiththesectionsize≤60mm×60mm(includeroundandsquarecoldformedsteelsectionwhichhavethesameperimeter)andsidethicknessratio≤14,theelongationafterfractureoftheflatpartshallbenolessthan17%.6.4Surfacequality6.4.1Thesurfaceofcoldformedsteelsectionsshallbefre