Designation:A821/A821M−15StandardSpecificationforSteelWire,Hard-DrawnforPrestressedConcreteTanks1ThisstandardisissuedunderthefixeddesignationA821/A821M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thisspecificationcoversuncoated,high-strength,hard-drawnsteelwireforuseintheconstructionofprestressedconcretetanksandsimilarstructures.Inapplication,thewireiscontinuouslywrappedonthestructuremaintainingtensionbyadeviceusingawiredrawingdie,ormechanicaltensioningsystemwithoutre-drawing.1.2Thisspecificationisapplicableonlytotheconditionofthewireasdeliveredtothepurchaser.Itisnotapplicabletothepropertiesorconditionofthewireafterapplication.1.2.1TypeAwireistobetensionedbydrawingthroughawiredrawingdieorbyamechanicalsystemwithoutre-drawing.1.2.2TypeBwireisdrawntofinishedsizebythemanu-facturerfortensioningbyamechanicalsystemwithoutre-drawing.NOTE1—TypeAwire,whentensionedbydrawingthroughadie,maynotfunctionproperlyifthepurchaserdoesnotensurethatduringapplicationthesurfaceofthewireisfreeofrustandforeignmaterialsthatcanbedetrimentaltogoodwiredrawingpractice.Further,thepurchasershouldensurethatproperwiredrawingtechniquesarefollowed,includingadequatelubrication,cooling,andproperdiemechanics.1.3Thetextofthisstandardreferencesnotesandfootnoteswhichprovideexplanatorymaterial.Thesenotesandfootnotes(excludingthoseintablesandfigures)shallnotbeconsideredasrequirementsofthestandard.1.4Thisspecificationisapplicableforordersineitherinch-poundsunits(asSpecificationA821)orinSIunits(asSpecificationA821M).1.5Thevaluesstatedineitherinch-poundunitsorSIunitsaretoberegardedseparatelyasstandard.Withinthetext,theSIunitsareshowninbrackets.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresult...
