weld defect 01
DESCRIPTION
thanksTRANSCRIPT
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Defect of Welding
Ir.Soeweify, M.Eng Head of Strength and Structure Groups
Department of Shipbuilding Engineering Surabaya Institute of Technology
Welding Engineer 1980 Hiroshima University Welding Inspector 1984 Hamburg University
Fracture mechanic sertificate 1990 Bandung Institute of Technology
Welding defect
Metallurgical defect Melting process
Incomplete fusion and incomplete penetration
Alloying process Slag inclusion and porousity
Cristalization process Cold crack and hot crack
Dimensional defect Tranversal shrinkage
Angular distortion
Longitudinal shrinkage Longitudinal distortion
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Weld defect
Crack
Incomplete fusion
Incompl. penetration
Slag inclusion
Porosity
Under cut
Underfill
Over lap
Covexity
Weld reinforcement
Arc strike
Tungten Inclusion
Spatter
Delamination
Lamelar tear
Seams/lap
Dimensional
Defect of Welding
Metallurgical defect
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Crack of welding
Hot crack, Cold crack
Longitudinal crack, Transversal crack
Base metal ,Weld metal ,HAZ crack
Throat, root, toe, under bead, crater crack
Lamelar tearing
Hot Crack
Just start for cristalization
Segregeration between cristal
Weld metal crack
Crack of the first layer
Creater crack
Micro crack
Transversal and logitudinal crack
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The influence of hot cracking
Name of
crack
Form of crack
Influence factor for cold
cracking
Wcond Chem Rs Bform
Crack on
the first
layer
V V V V V V V V V
Dendrite
crack
V V V V V V V V V V
Crater crack V V V V V
V
V V
Hot Crack
Welding condition
Chemical composition
Shrinking load of weld point
Form of bead
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Crater 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
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Cr- Mo
Midle sensitive necc care
Midle sensitive necc to care
Low sensitive No Problem
Midle sensitive necc to care
Low sensitive No Problem
1Cr Mo
Midle sensitive necc to care
Midle sensitive necc Care
Low sensitive No Problem
Midle sensitive necc care
Low sensitive No Problem
1 Cr Mo
Midle sensitive necc care
Midle sensitive necc Care
Low sensitive No Problem
Midle sensitive necc care
Low sensitive No Problem
2 Cr 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 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 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
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Cold crack
Process of crack
Finish cristalization
Hydrogen diffusible
Stress at the weld metal
HAZ and base metal crack
Root crack
Toe crack
Under bead crack
Caused of crack
Chemical composition
Welding heat input
Hydrogen diffusible
Restraint of joint
Residual stress
Diforation anggle
The influence of cold cracking
Name
of
crack
Form of crack Influence factor for cold
cracking
Wh Hdiff Pcm R A Rs
Root
crack
V V V V
V
V V
V
V V
V
V V
V
V V V V
V
V V V V V
V
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The influence of cold cracking
Name
of
crack
Form of crack
Influence factor for cold
cracking
Wh Hd Pcm R A Rs
Toe
crack
V V V V
V
V V
V
V V V
V
V V V V
V
V V V
The influence of cold cracking
Name
of
crack
Form of crack
Influence factor for cold
cracking
Wh Hd Pcm R A Rs
Under
bead
crack
V V V V
V
V V V V V V
V
Lame
lar
tear
ing
V V V V V V
V
V V
V
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Longitudinal 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 crack
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Under 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 craking
Experimental results
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Couse and Prevention Cracks on the HAZ
Couse
Base metal have high hardenability
High C ek and P cm
C, Mn,Cr conten to high
Hidrogen diffusible
Hidrogen Embrittlemen
High restrain joint
Preventive
Chose the lower Cek and Pcm
Elec. Low hydrogen
Dry Filler metal
Clean edge preparation
Moderate high restrain
Good weather
Pre heating and post heating
Lamelar tearing
Thick 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
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Lamellar tearing
Lamellar tearing
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Lamellar tearing
Lamelar tearing
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Lamelar tearing
Lamelar tearing Lamellar tearing
Incomplete fusion
Low heat input
Travel speed to high
Amperage to low
Wrong electrode position
Weld metal to weld metal
Weld metal to base metal
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Incomplete fusion
Typical side wall incomplete
fusion
Incomplete penetration
Couse of Incomlete penetration Diameter electrode to big Groove angle to small Amperage to low Wrong electrode not deep penetration
Weld metal does not extend entirely
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Incomplete penetration
Incomplete penetration
on radiography Incomplete penetration
in root of weld
Slag inclusion
Incorrect welding parameter
Difficult to clean slack
Molten slack to thick
Oxidation and deoxidation process
Unadequate weld preparation
Iregular visual in X Ray
Black vision on DT
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Porosity
Gas entrapment during solidification
The least dangerous
H2S, CO, NO2 Uniformly scattered
Clustered porosity
Piping porosity
Linear porosit
Dirty base metal
Under cut
Under Cut
Amperage to high
The wrong welding technique
Angle of electrode during welding
Initial crack start from this defect
Maximum 0.5 mm
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Under fill
Over lap
Over lap
Protrusion of weld metal beyond the
weld toe
Wrong electrode position
Burn torch