Weld Symbols on a Drawing

WeldSymbolsonaDrawing–RefreshYour KnowledgeANSI/AWSA2.479The eight elements which may appear in a welding symbol are:
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Weld Symbols on a Drawing WeldSymbolsonaDrawing–RefreshYour KnowledgeANSI/AWSA2.479The eight elements which may appear in a welding symbol are:referenceline,arrow,basicweldsymbols,dimensionsandotherdata, supplementary symbols, finish symbols, tail and specification and processorotherreference.Letusdiscusstheonebyone.Reference Line: This is the basis of the welding symbol. All otherelementsareorientedwithrespecttothisline.Thearrowisaffixedtooneend and a tail, when necessary, is affixed to the other. Arrow:Thisconnectsthereferencelinetoonesideofthejointinthecaseofgroove,fillet,flange,andflashorupsetweldingsymbols.Thissideofthe joint is known as the arrow side of the joint. The opposite side isknownastheothersideofthejoint.Inthecaseofplug,slot,projection,andseamweldingsymbols,thearrowconnectsthereferencelinetotheoutersurfaceofoneofthemembersofthejointatthecenterlineoftheweld.Inthiscasethemembertowhichthearrowpointsisthearrowsidemember:theothermemberistheothersidemember.Inthecaseofbeveland Jgroove weld symbols, a twodirectional arrow pointing toward amemberindicatesthatthememberistobechamfered.Basic Weld Symbols: These designate the type of welding to beperformed.ThebasicsymbolswhichareshowninthetableBasicWeldSymbols are placed approximately in the center of the reference line,eitheraboveorbelowitoronbothsidesofitasshowninabovefigure.Welds on the arrow side of the joint are shown by placing the weldsymbolsonthesideofthereferencelinetowardsthereader(lowerside).Welds on the other side of the joint are shown by placing the weldsymbols on the side of the reference line away from the reader (upperside).SupplementarySymbols:Theseconveyadditionalinformationrelativetotheextentofthewelding,wheretheweldingistobeperformed,andthecontouroftheweldbead.The“weldallaround”and“field”symbolsareplacedattheendofthereferencelineatthebaseofthearrowasshowninfirstfigureandthetableSupplementaryWeldSymbols.Dimensions:Theseincludethesize,length,spacing,etc.,oftheweldorwelds.Thesizeoftheweldisgiventotheleftofthebasicweldsymbolandthelengthtotheright.Ifthelengthisfollowedbyadashandanothernumber,thisnumberindicatesthecentertocenterspacingofintermittentwelds.Otherpertinentinformationsuchasgrooveangles,includedangleofcountersinkforplugweldsandthedesignationofthenumberofspotorprojectionweldsarealsolocatedaboveorbelowtheweldsymbol.Thenumber designating the number of spot or projection welds is alwaysenclosed in parentheses. ContourandFinishSymbols: Thecontoursymbolisplacedaboveorbelowtheweldsymbol.Thefinishsymbolalwaysappearsaboveorbelowthecontoursymbol.Thefollowingfinishsymbolsindicatethemethod,notthe degrees of finish: C—chipping; G—grinding; M—machining; R—rolling;andH—hammering.Tail:Thetailwhichappearsontheendofthereferencelineoppositetothearrowendisusedwhenaspecification,process,orotherreferenceismade inthe welding symbol. Whenno specification,process, or otherreferenceisusedwithaweldingsymbol,thetailmaybeomitted.