Weld Defect 01 New
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Transcript of Weld Defect 01 New
Defect of Welding Defect of Welding
Ir.Soeweify, M.EngIr.Soeweify, M.EngHead of Strength and Structure Groups Head of Strength and Structure Groups Department of Shipbuilding EngineeringDepartment of Shipbuilding Engineering
Surabaya Institute of TechnologySurabaya Institute of Technology
Welding Engineer 1980 Hiroshima UniversityWelding Engineer 1980 Hiroshima UniversityWelding Inspector 1984 Hamburg UniversityWelding Inspector 1984 Hamburg University
Fracture mechanic sertificate 1990 Bandung Institute of Fracture mechanic sertificate 1990 Bandung Institute of TechnologyTechnology
Welding defectWelding defect
Metallurgical defect Metallurgical defect Melting processMelting process
• Incomplete fusion and incomplete penetrationIncomplete fusion and incomplete penetration Alloying processAlloying process
• Slag inclusion and porousitySlag inclusion and porousity Cristalization processCristalization process
• Cold crack and hot crackCold crack and hot crack
Dimensional defectDimensional defect Tranversal shrinkageTranversal shrinkage
• Angular distortionAngular distortion Longitudinal shrinkageLongitudinal shrinkage
• Longitudinal distortionLongitudinal distortion
Weld defectWeld defect
CrackCrack Incomplete fusionIncomplete fusion Incompl. penetrationIncompl. penetration Slag inclusionSlag inclusion PorosityPorosity Under cutUnder cut UnderfillUnderfill Over lapOver lap
CovexityCovexity Weld reinforcementWeld reinforcement Arc strikeArc strike Tungten InclusionTungten Inclusion SpatterSpatter DelaminationDelamination Lamelar tearLamelar tear Seams/lapSeams/lap Dimensional Dimensional
Defect of WeldingDefect of Welding
Metallurgical defectMetallurgical defect
Crack of weldingCrack of welding
Hot crack, Cold crackHot crack, Cold crack Longitudinal crack, Longitudinal crack,
Transversal crack Transversal crack Base metal ,Weld Base metal ,Weld
metal ,HAZ crackmetal ,HAZ crack Throat, root, toe, Throat, root, toe,
under bead, crater under bead, crater crack crack
Lamelar tearingLamelar tearing
Hot CrackHot Crack
Just start for cristalizationJust start for cristalization Segregeration between cristalSegregeration between cristal Weld metal crackWeld metal crack Crack of the first layerCrack of the first layer Creater crackCreater crack Micro crackMicro crack Transversal and logitudinal crackTransversal and logitudinal crack
The influence of hot crackingThe influence of hot cracking
Name of Name of crackcrack
Form of crackForm of crack Influence factor for cold Influence factor for cold crackingcracking
WWcondcond CChemhem RsRs BBformform
Crack on Crack on the first the first layerlayer
V V VV V V V V V V V V V V V VV V
Dendrite Dendrite crackcrack
V V VV V V V V V V V VV V V V VV V V
Crater crackCrater crack V V VV V V V V V V VV
VV VV
Hot CrackHot Crack
Welding conditionWelding condition Chemical Chemical
compositioncomposition Shrinking load of weld Shrinking load of weld
pointpoint Form of beadForm of bead
Crater crackCrater crack
Crater crack occour in the end of weld couse of wrong welding electrode manipulation, Filler metal have flow characteristiecs with produce concave profile when solidification
Hot crack start from crater crack of fillet weld in pipe welding, E 308 -16, E 309-16, E 316 -16, The welder must take care the end of welding to full fill the crater
Crater crack is one of dangerous hot crack
Preventive Methode of the Hot cracking for each material
Sensitivity Preventive Methods
Crack of Weld Metal For Material
For Prose dur
For De sign
Kind of Material First Layer
Crack Dendrit Crack
Micro Crack HAZ
Other Crack
Crack
In the
HAZ
40 Kg/mm2
Midle sensitive necc to care
Midle sensitive necc to care
Low sensitive No Problem
Midle sensitive necc to care
Low sensitive No Problem
50 Kg/mm2
Midle sensitive necc care
Midle sensitive necc Care
Low sensitive No Problem
Midle sensitive necc care
Low sensitive No Problem
60 Kg/mm2
Midle sensitive necc care
Midle sensitive necc Care
Low sensitive No Problem
Midle sensitive necc care
Low sensitive No Problem
70 Kg/mm2
Midle sensitive necc to care
Midle sensitive necc to care
Low sensitive No Problem
Midle sensitive necc to care
Midle sensitive necc to care
C A R B O N S T E E L
80 Kg/mm2
Midle sensitive necc care
Midle sensitive necc care
Low sensitive No Problem
Midle sensitive necc care
Midle sensitive necc to care
Reduce of P.S Increase of Mn examine of the elememt
Examine weld condition examine format weld bead.
Low Shrink age Pre vent Stress
Cr- ½ Mo
Midle sensitive necc care
Midle sensitive necc to care
Low sensitive No Problem
Midle sensitive necc to care
Low sensitive No Problem
1Cr – ½ Mo
Midle sensitive necc to care
Midle sensitive necc Care
Low sensitive No Problem
Midle sensitive necc care
Low sensitive No Problem
1 ¼ Cr – ½ Mo
Midle sensitive necc care
Midle sensitive necc Care
Low sensitive No Problem
Midle sensitive necc care
Low sensitive No Problem
2 ¼ Cr – ½ Mo
Midle sensitive necc care
Midle sensitive necc to care
Low sensitive No Problem
Midle sensitive necc to care
Low sensitive No Problem
3 Cr – ½ Mo
Midle sensitive necc to care
Midle sensitive necc Care
Low sensitive No Problem
Midle sensitive necc care
Low sensitive No Problem
5 – 9 Cr – ½ Mo
Midle sensitive necc care
Midle sensitive necc to care
Low sensitive No Problem
Midle sensitive necc to care
Low sensitive No Problem
L O W A L L O Y S T E E L
Mn - Mo Midle sensitive necc care
Midle sensitive necc care
Low sensitive No Problem
Midle sensitive necc care
Low sensitive No Problem
Reduc of P.S Increase of Mn Examined of the elememt
Examine weld codition Examine format weld bead. Clean Keep enough Slag
Low Shrink age Pre vent SC
Preventive Methode of the Hot cracking for each material
Preventive Methode of the Hot cracking for each material
Austenit Midle sensitive necc to care
Midle sensitive necc care
High sensitive Must care
Midle sensitive necc care
Midle sensitive necc to care
Martensit Midle sensitive necc care
Midle sensitive necc to care
Midle sensitive necc to care
Midle sensitive necc to care
Midle sensitive necc to care
S T A I N L E E S
Ferrit Midle sensitive necc care
Midle sensitive necc care
Midle sensitive not care
High Sensitive Must care
Midle sensitive necc to care
Reduc of P.S Increase of Mn Examin of the element Reduced Harmful element Pb,B,O Keep delts ferrite
Examine weld codition Take of crater Examine format weld bead. Clean Keep enough Slag
Low Shrink age Prevent Stress Concent
Pure Nikkel
High sensitive Must care
Midle sensitive necc care
High sensitive Must care
High sensitive Must care
Midle sensitive necc to care
Inconnel High sensitive Must care
High sensitive Must care
High sensitive Must care
High sensitive Must care
High sensitive Must care
Hactelloy High sensitive Must care
Midle sensitive necc care
Midle sensitive necc care
High sensitive Must care
Midle sensitive necc to care
N I
B A S E
Monel High sensitive Must care
High sensitive Must care
High sensitive Must care
High sensitive Must care
Midle sensitive necc to care
Reduce PS Increase Mn Reduce Harmful elemen, Pb,B,O Add little element Ti,Nb.Al,Ni Examine element comp
Examine weld codition Examine format weld bead. Clean Keep enough Slag Apply peening
Low Shrink age Prevent Stress
Cold crackCold crack
Process of crackProcess of crack Finish cristalizationFinish cristalization Hydrogen diffusibleHydrogen diffusible Stress at the weld Stress at the weld
metalmetal HAZ and base metal HAZ and base metal
crackcrack Root crackRoot crack Toe crackToe crack Under bead crackUnder bead crack
Caused of crackCaused of crack Chemical composition Chemical composition Welding heat inputWelding heat input Hydrogen diffusibleHydrogen diffusible Restraint of jointRestraint of joint Residual stressResidual stress Diforation anggleDiforation anggle
The influence of cold crackingThe influence of cold cracking
Name Name of of
crackcrack
Form of crackForm of crack Influence factor for cold Influence factor for cold crackingcracking
WhWh HHdiffdiff PPcmcm RR AA RsRs
Root Root crackcrack
V VV V V V V V VV
V V V V VV
V V V V VV
V V V V VV
V VV V V V V V VV
V VV V VV V V V V VV
The influence of cold crackingThe influence of cold cracking
Name Name of of
crackcrackForm of crackForm of crack
Influence factor for cold Influence factor for cold crackingcracking
WhWh HdHd PPcmcm RR AA RsRs
Toe Toe crackcrack
V VV V V V V V VV
V V V V VV
VV V V V V VV
V VV V V V V V VV
VV VV VV
The influence of cold crackingThe influence of cold cracking
Name Name of of
crackcrackForm of crackForm of crack
Influence factor for cold Influence factor for cold crackingcracking
WhWh HdHd PPcmcm RR AA RsRs
UnderUnder
bead bead crackcrack
V VV V V V V V VV
V VV V V VV V V V V V VV
LameLame
lar lar teartear
inging
VV V VV V VV V V V V VV
V V V V VV
Longitudinal and transversal crackLongitudinal and transversal crack
Longitudinal crack start from the weld toe in the HAZ
Transvers crack start from the stop and run of weld
Longitudinal and transversal crackLongitudinal and transversal crack
Under bead crackUnder bead crack
Under bead crack
Some kind of cold
crack
Start from the toe of
weld in HAZ
Mainly caused by
Hydrogen diffusible
Effect of pre heating on root crakingEffect of pre heating on root craking
Experimental resultsExperimental results
Hydrogen CrackingHydrogen Cracking Hydrogen cracking, also called Hydrogen cracking, also called
cold cracking, requires all three cold cracking, requires all three of these factorsof these factors HydrogenHydrogen StressStress Susceptible microstructure (high Susceptible microstructure (high
hardness)hardness) Occurs below 300°COccurs below 300°C Prevention by Prevention by
Preheat slows down the cooling Preheat slows down the cooling rate; this can help avoid martensite rate; this can help avoid martensite formation and supplies heat to formation and supplies heat to diffuse hydrogen out of the materialdiffuse hydrogen out of the material
Low-hydrogen welding procedureLow-hydrogen welding procedure
Cracking in Welds
0.1.1.5.2.T12.95.12
Hydrogen CrackingHydrogen Cracking Hydrogen cracking, also called Hydrogen cracking, also called
cold cracking, requires all three cold cracking, requires all three of these factorsof these factors HydrogenHydrogen StressStress Susceptible microstructure (high Susceptible microstructure (high
hardness)hardness) Occurs below 300°COccurs below 300°C Prevention by Prevention by
Preheat slows down the cooling Preheat slows down the cooling rate; this can help avoid martensite rate; this can help avoid martensite formation and supplies heat to formation and supplies heat to diffuse hydrogen out of the materialdiffuse hydrogen out of the material
Low-hydrogen welding procedureLow-hydrogen welding procedure
Cracking in Welds
0.1.1.5.2.T12.95.12
Hydrogen CrackingHydrogen Cracking Hydrogen cracking, also called Hydrogen cracking, also called
cold cracking, requires all three cold cracking, requires all three of these factorsof these factors HydrogenHydrogen StressStress Susceptible microstructure (high Susceptible microstructure (high
hardness)hardness) Occurs below 300°COccurs below 300°C Prevention by Prevention by
Preheat slows down the cooling Preheat slows down the cooling rate; this can help avoid martensite rate; this can help avoid martensite formation and supplies heat to formation and supplies heat to diffuse hydrogen out of the materialdiffuse hydrogen out of the material
Low-hydrogen welding procedureLow-hydrogen welding procedure
Cracking in Welds
0.1.1.5.2.T12.95.12
Couse and Prevention Cracks on Couse and Prevention Cracks on the HAZ the HAZ
CouseCouse Base metal have high Base metal have high
hardenabilityhardenability High C ek and P cm High C ek and P cm C, Mn,Cr conten to C, Mn,Cr conten to
highhigh Hidrogen diffusibleHidrogen diffusible Hidrogen Hidrogen
EmbrittlemenEmbrittlemen High restrain joint High restrain joint
PreventivePreventive Chose the lower Cek Chose the lower Cek
and Pcm and Pcm Elec. Low hydrogenElec. Low hydrogen Dry Filler metal Dry Filler metal Clean edge Clean edge
preparationpreparation Moderate high restrainModerate high restrain Good weatherGood weather Pre heating and post Pre heating and post
heatingheating
Lamelar tearingLamelar tearingThick material only
Delamination first
High Stress through the thickness
Fillet weld only
Degree of constraint
High inclusion of base metal
Low transverse ductility
High residual stress
Lamellar tearing
Lamellar tearing
Lamellar tearing
Lamelar tearingLamelar tearing
Lamelar tearingLamelar tearing Lamelar tearingLamelar tearing Lamellar tearingLamellar tearing
Lamellar TearingLamellar Tearing Occurs in thick plate subjected to high Occurs in thick plate subjected to high
transverse welding stresstransverse welding stress Related to elongated non-metallic inclusions, Related to elongated non-metallic inclusions,
sulfides and silicates, lying parallel to plate sulfides and silicates, lying parallel to plate surface and producing regions of reduced surface and producing regions of reduced ductilityductility
Prevention byPrevention by Low sulfur steelLow sulfur steel Specify minimum ductility levels in transverse Specify minimum ductility levels in transverse
directiondirection Avoid designs with heavy through-thickness Avoid designs with heavy through-thickness
direction stressdirection stress
Cracking in Welds
0.1.1.5.2.T14.95.12
Improve CleanlinessImprove through thickness properties
Buttering
Reheat CrackingReheat Cracking Mo-V and Mo-B steels susceptibleMo-V and Mo-B steels susceptible Due to high temperature embrittlement of the heat-Due to high temperature embrittlement of the heat-
affected zone and the presence of residual stressaffected zone and the presence of residual stress Coarse-grained region near fusion line most Coarse-grained region near fusion line most
susceptiblesusceptible Prevention byPrevention by
Low heat input weldingLow heat input welding Intermediate stress relief of partially completed weldsIntermediate stress relief of partially completed welds Design to avoid high restraintDesign to avoid high restraint Restrict vanadium additions to 0.1% in steelsRestrict vanadium additions to 0.1% in steels Dress the weld toe region to remove possible areas of Dress the weld toe region to remove possible areas of
stress concentrationstress concentration
Cracking in Welds
0.1.1.5.2.T15.95.12
Knife-Line Attack in the HAZKnife-Line Attack in the HAZ CrCr2323CC66 precipitate in precipitate in
HAZHAZ Band where peak Band where peak
temperature is 800-temperature is 800-1600°F1600°F
Can occur even in Can occur even in stabilized gradesstabilized grades Peak temperature Peak temperature
dissolves titanium dissolves titanium carbidescarbides
Cooling rate doesn’t Cooling rate doesn’t allow them to form againallow them to form again
Weld
HAZ
Knife-line attack
Stainless Steel
Lamellar TearingLamellar Tearing Occurs in thick plate subjected to high Occurs in thick plate subjected to high
transverse welding stresstransverse welding stress Related to elongated non-metallic inclusions, Related to elongated non-metallic inclusions,
sulfides and silicates, lying parallel to plate sulfides and silicates, lying parallel to plate surface and producing regions of reduced surface and producing regions of reduced ductilityductility
Prevention byPrevention by Low sulfur steelLow sulfur steel Specify minimum ductility levels in transverse Specify minimum ductility levels in transverse
directiondirection Avoid designs with heavy through-thickness Avoid designs with heavy through-thickness
direction stressdirection stress
Cracking in Welds
0.1.1.5.2.T14.95.12
Improve CleanlinessImprove through thickness properties
Buttering
Reheat CrackingReheat Cracking Mo-V and Mo-B steels susceptibleMo-V and Mo-B steels susceptible Due to high temperature embrittlement of the heat-Due to high temperature embrittlement of the heat-
affected zone and the presence of residual stressaffected zone and the presence of residual stress Coarse-grained region near fusion line most Coarse-grained region near fusion line most
susceptiblesusceptible Prevention byPrevention by
Low heat input weldingLow heat input welding Intermediate stress relief of partially completed weldsIntermediate stress relief of partially completed welds Design to avoid high restraintDesign to avoid high restraint Restrict vanadium additions to 0.1% in steelsRestrict vanadium additions to 0.1% in steels Dress the weld toe region to remove possible areas of Dress the weld toe region to remove possible areas of
stress concentrationstress concentration
Cracking in Welds
0.1.1.5.2.T15.95.12
Knife-Line Attack in the HAZKnife-Line Attack in the HAZ CrCr2323CC66 precipitate in precipitate in
HAZHAZ Band where peak Band where peak
temperature is 800-temperature is 800-1600°F1600°F
Can occur even in Can occur even in stabilized gradesstabilized grades Peak temperature Peak temperature
dissolves titanium dissolves titanium carbidescarbides
Cooling rate doesn’t Cooling rate doesn’t allow them to form againallow them to form again
Weld
HAZ
Knife-line attack
Stainless Steel
Incomplete fusionIncomplete fusion
Low heat inputLow heat input Travel speed to highTravel speed to high Amperage to lowAmperage to low Wrong electrode Wrong electrode
positionposition Weld metal to weld Weld metal to weld
metal metal Weld metal to base Weld metal to base
metalmetal
Incomplete fusionIncomplete fusion
Typical side wall incomplete fusion
Incomplete penetration Incomplete penetration
Couse of Incomlete penetrationDiameter electrode to bigGroove angle to smallAmperage to lowWrong electrode not deep penetration Weld metal does not extend entirelyWeld metal does not extend entirely
Incomplete penetration Incomplete penetration
Incomplete penetration on radiography
Incomplete penetration in root of weld
Incomplete fusion
Incompete Penetration
Slag inclusionSlag inclusion
Incorrect welding Incorrect welding parameterparameter
Difficult to clean slackDifficult to clean slack Molten slack to thickMolten slack to thick Oxidation and Oxidation and
deoxidation processdeoxidation process Unadequate weld Unadequate weld
preparationpreparation Iregular visual in X RayIregular visual in X Ray Black vision on DTBlack vision on DT
PorosityPorosity
Gas entrapment Gas entrapment during solidificationduring solidification
The least dangerousThe least dangerous HH22S, CO, NOS, CO, NO22
Uniformly scatteredUniformly scattered Clustered porosityClustered porosity Piping porosityPiping porosity Linear porositLinear porosit Dirty base metalDirty base metal
Under cut Under cut Under CutUnder Cut
Amperage to highAmperage to high The wrong welding The wrong welding
techniquetechnique Angle of electrode Angle of electrode
during weldingduring welding Initial crack start from Initial crack start from
this defectthis defect Maximum 0.5 mmMaximum 0.5 mm
Under fillUnder fill
Over lapOver lap
Over lapOver lap Protrusion of weld Protrusion of weld
metal beyond the metal beyond the
weld toeweld toe Wrong electrode Wrong electrode
positionposition Burn torchBurn torch
UNDERCUTUNDERCUT
POROSITYPOROSITY
INCOMPLETE FUSIONINCOMPLETE FUSION
OVERLAPOVERLAP
UNDERFILLUNDERFILL
SPATTERSPATTER
EXCESSIVE CONVEXITYEXCESSIVE CONVEXITY
EXCESSIVE CONCAVITYEXCESSIVE CONCAVITY
EXCESSIVE WELD EXCESSIVE WELD REINFORCEMENTREINFORCEMENT
INCOMPLETE PENETRATIONINCOMPLETE PENETRATION&&
EXCESSIVE PENETRATIONEXCESSIVE PENETRATION
UNACCEPTABLEUNACCEPTABLEWELD PROFILESWELD PROFILES