defects on weld bead

7/30/2019 Defects on Weld BEAD

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Root bead width

Excess weld metalheight

Root penetration

Weld cap width

Butt weldsButt welds -- SizeSize


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x

x

x

Butt weldsButt welds --ProfileProfile


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Butt weldsButt welds -- Toe BlendToe Blend

x

x

x


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Butt weldsButt welds -- Weld WidthWeld Width


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Excess Weld MetalExcess Weld Metal

Excess capExcess capreinforcementreinforcement

Under FillUnder Fill

IncompleteIncompletefilled groovefilled groove


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Incompletely Filled GrooveIncompletely Filled Groove


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Poor RestartPoor Restart

Poor stop/starts


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Cap undercutCap undercut

Cap UndercutCap Undercut


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OverlapOverlap

OverlapOverlap


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DEFINITION:

An imperfection at the toe

or root of a weld caused

by metal flowing onto the

surface of the parent platewithout fusing to it.

CAUSES:

Contamination

Slow travel speed

High amperage

Welding technique

OverlapOverlap


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OverlapOverlap

OverlapOverlap


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CausesCauses

Improper welding techniqueImproper welding technique

Insufficient weld metal depositedInsufficient weld metal deposited

Lack of FusionLack of Fusion


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`Inter run Incompletely Filled GrooveInter run Incompletely Filled Groove

CausesCauses

Improper welding techniqueImproper welding technique Insufficient weld metal depositedInsufficient weld metal deposited


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Slag InclusionsSlag Inclusions -- CapCap

CausesCauses

Insufficient cleaning between passesInsufficient cleaning between passes

Contaminated weld preparationContaminated weld preparation

Welding over irregular profileWelding over irregular profile

Incorrect welding speedIncorrect welding speed

Arc length too longArc length too long


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Gas pores / PorosityGas pores / Porosity

CausesCauses

Low welding currentLow welding current


ExcessiveExcessive moisture in flux or preparationmoisture in flux or preparation ContaminatedContaminated preparationpreparation

Damaged electrode fluxDamaged electrode flux

Removal of gas shieldRemoval of gas shield


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CausesCauses

Excessive arc energyExcessive arc energy

Excessive arc lengthExcessive arc length

Damp electrodesDamp electrodes Arc blowArc blow

SpatterSpatter


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Arc Str ikesArc Str ikes

CausesCauses

Electrode straying ontoElectrode straying onto

parent metalparent metal

Electrode holder with poorElectrode holder with poorinsulationinsulation

Poor contact of earthPoor contact of earth

clampclamp


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Chisel MarksChisel MarksChisel Marks Pitting Corrosion Grinding Marks

Mechanical damage can be defined as any surfaceMechanical damage can be defined as any surface

material damage cause during the manufacturingmaterial damage cause during the manufacturing

process. This can included damage caused by:process. This can included damage caused by:

GrindingGrinding HammeringHammering ChisellingChiselling ChippingChipping

Breaking off welded attachments (torn surfaces)Breaking off welded attachments (torn surfaces)

Using needle guns to compress weld capping runsUsing needle guns to compress weld capping runs


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CraterCraterCrackCrackandandpipepipe


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PorosityPorosity

Cluster porosityCluster porosity


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Gas poresGas pores

PorosityPorosity

PorosityPorosity


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Cluster PorosityCluster Porosity

ClusterCluster

porosityporosity


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Worm Hole

HerringboneHerringbone

porosityporosity


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Lack of FusionLack of Fusion

Causes Amperage too low Contaminated weldpreparation Amperage too high(welder increasesspeed of travel)


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Slag inclusionsSlag inclusions Lack of sidewallLack of sidewallfusion withfusion with

associated slagassociated slag

Lack of interun fusionLack of interun fusion

+ slag+ slagParallel slag linesParallel slag lines


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Lack of side Wall FusionLack of side Wall Fusion

Lack ofLack ofsidewall fusionsidewall fusion


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Slag InclusionSlag Inclusion

Interpass slagInterpass slaginclusionsinclusions


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Slag InclusionsSlag Inclusions

CausesCauses


Incorrect welding speedIncorrect welding speed

Insufficient cleaning between passesInsufficient cleaning between passes

Contaminated weld preparationContaminated weld preparation

Welding over irregular profileWelding over irregular profile


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Wagon TrackWagon Track

ElongatedElongatedslag linesslag lines


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Tungsten InclusionsTungsten Inclusions

CausesCauses

Contamination of weld Caused by tungsten touchingContamination of weld Caused by tungsten touchingweld metal or parent metal during welding using theweld metal or parent metal during welding using the

TIG welding processTIG welding process


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CausesCauses

Excessive amperage duringExcessive amperage during

welding of rootwelding of root

Excessive root gapExcessive root gap

Poor fit upPoor fit up Excessive root grindingExcessive root grinding

Improper welding techniqueImproper welding technique

Excess PenetrationExcess Penetration


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CausesCauses

Too small a root gapToo small a root gap

Arc too longArc too long

Wrong polarityWrong polarity

Electrode too large for jointElectrode too large for joint

preparationpreparation

Incorrect electrode angleIncorrect electrode angle

Too fast a speed of travel for currentToo fast a speed of travel for current

L.O.PL.O.P


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Root L.O.FRoot L.O.F

Lack of rootLack of root

fusionfusion


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Lack ofLack of

fusionfusion

IncompleteIncomplete

PenetrationPenetration

Root Welding DefectsRoot Welding Defects


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Root L.O.FRoot L.O.F

CausesCausesToo small a root gapToo small a root gap

Arc too longArc too longWrong polarityWrong polarity

Electrode too large for jointElectrode too large for joint

preparationpreparation

Incorrect electrode angleIncorrect electrode angle

Too fast a speed of travel forToo fast a speed of travel for

currentcurrent


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Root Concavity

Roo t concav it yRoo t con cav i t y


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Root ConcavityRoot Concavity

CausesCauses

Root gap too largeRoot gap too large

Insufficient arc energyInsufficient arc energy Excessive back purge TIGExcessive back purge TIG


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Burn ThroughBurn Through

CausesCauses

Excessive root grindingExcessive root grinding

Excessive amperage during welding of rootExcessive amperage during welding of root Improper welding techniqueImproper welding technique

Slow travel speedSlow travel speed

Large root gap/small root face (irregular fit up)Large root gap/small root face (irregular fit up)


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Burn Through

A h l l d b i i h ldA h l l d b t t i i t h ld


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Shrinkage grooveShrinkage groove

I n su f f i ci en t w e ld m e ta l I n su f f i ci en t w e ld m e ta l

deposi t ed i n t he roo tdeposi t ed i n t he roo t

passpass

Too fas t a coo l ing ra t eToo fas t a coo l ing ra t e

du r i ng t he app l icat i on o fdu r i ng t he app l icat i on o f

t he roo t bead passt he roo t bead pass

Poo r w e ld i ng techn i quePoo r w e ld i ng techn i que

A sha l low g roove caused by con t ract i on i n th e w e ldA sha l low g roove caused by con t ract i on i n th e w e ld

m e ta l al ong each si de o f t h e pene t ra t i on b ead o rm e ta l a long each s i de o f t he pene t ra t i on bead o r

can occu r i n t he cen te r o f t he w e ld beadcan occu r i n t he cen te r o f t he w e ld bead

Shrinkage grooveShrinkage groove


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Root pipingRoot piping


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Root undercutRoot undercut

CausesCauses Root gap too largeRoot gap too large

Excessive arc energyExcessive arc energy

Small or no root faceSmall or no root face

Root undercutRoot undercut


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NonNon--alignment of two abutting edgesalignment of two abutting edges

Also Known as: Hi Low. Mismatch. or MisalignmentAlso Known as: Hi Low. Mismatch. or Misalignment

2mm

Alignment ImperfectionAlignment Imperfection


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50mm

3mm

Angular distortion.

Measure the distance to the edge of the plate (50mm).

Use a straight edge (rule) to find the amount of distortion

then measure the space (3mm).

This reported as Angular distortion 3mm in 50mm

defects on weld bead

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