Transcript
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TYPICAL WELDINGFAULTS
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Typical Welding Faults
Root faults
Fusion faults
Slag inclusions
Pores
Cracks
Unmelted
edgeUndercutt
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Typical Welding Faults
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Typical Welding Faults
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Typical Welding Faults
70
2-2,5mm
35
1,5mm
Root faults Edge preparation
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Typical Welding FaultsRoot faults Amperage setting
Manipulating electrode
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Typical Welding FaultsFusion faults Amperage setting
Manipulating electrode
Too low amperage setting
Edge preparation
Included angle not sufficient
90
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Typical Welding FaultsFusion faults
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Typical Welding FaultsSlag inclusions Amperage setting
Manipulating electrode
Placing of runs
Not removing slag
Trapped slag
Manipulating
electrode
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Typical Welding Faults
Trapped slag
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Typical Welding FaultsPores Hydrogen pores
From moist electrodes
Other sources are:
Rust, oil, paint or
condensation along
welding groove
Oxygen poresLong arc or other reasons
for insufficient arc shielding
N2 N2
O2 O2
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Typical Welding Faults
Reinforcement:
1,6 mm for manual welding
3,2 mm for automated
welding
Bead Crown
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Typical Welding Faults
Stresses are distributed more uniformly through a flat
or concave fil let weld.
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Typical Welding FaultsFusion faults
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Typical Welding FaultsFusion faults
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Typical Welding Faults
Max undercut according
to ASME:
Undercut deeper than 0,8 mm
and longer than 6 mm is
unacceptable
Undercut less than 0,8 mm
but longer than 6 mm must
be evaluated form case to
case depending on
circumstances
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Typical Welding Faults
Heat CracksImpurities in base
materialTension across weld
Cold CracksHydrogen cracks
HAZ cracks
Shrinkage CracksLengthwise shrinkage
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Typical Welding FaultsFusion faults
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Typical Welding FaultsFusion faults
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Typical Welding Faults.
Spray on
Cleaner
Apply Penetrant Wipe surfaceclean
Spray onDeveloper
Inspect Defects wil l showas bright red lines
in white developer
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Typical Welding Faults.
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Typical Welding Faults
Magna Flux CrackDetection Kit
3 pcs. Cleaner
2 pcs. Penetrant
3 pcs. Developer
193-653535
Cleaner SKC-S
10 pcs. of 400 ML in box
193-653543
Penetrant SKL-SP1
10 pcs. of 400 ML in box
193-653550
Developer SKD-S2
10 pcs of 400 ML in box
193-653568
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Typical Welding Faults
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Typical Welding Faults
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Typical Welding Faults
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INSPEKSJON AV SVEISEARBEID
FR SVEISINGEr grunnmaterialet i henhold til spesifikasjon? Kvalitet
Type
Dimensjon
Primer
Er overflaten fri for rust, olje, fett eller annen forurensning?Er materialflatene rette/i fasong, og uten skr?
Er fugeforbindelsen i henhold til spesifikasjon? ( vinkler, nesehyde, rotpning)
Er sveisemetoden i henhold til spesifikasjon? (Elektroder,TIG,MIG/MAG,UP)
Er tillsettmaterialet ( Elektroder, trd, pulver ) I henhold til spesifikasjon? (AWS,EN)
Er tilsettet godkjent i klasseselskap? (DNV,ABS,BV,GL,LR)Er gradering korekt? ( 3Y H10 for skrogkvalitet stl )
Er godkjennelsen oppdatert?
Har tilsettmaterialet blitt lagret korekt?
Elektroder,trd og pulver skal lagres i upnede
originale forpakninger
15- 25C Max 50% Relativ fukt ighet>25C Max 40% Relativ fuktighet
Er det krav t il forvarming av t ilsettet fr sveising?
Basiske og rustfrie elektroder kan for kritiske
aplikasjoner forvarmes til 300- 350C i 2 timerHar sveiseren den ndvendige kompetanse/ Godkjennelse?
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PRIOR TO WELDINGIs the base material according to specification? Quality
Type
Dimension
Primer
Is the surface free for rust, oil, grease or any other contamination?Is the material straight/ the right shape, and without cuts?
Is the edge preparation according to specif ication? ( angels, root face, root opening)
Is the welding method according to specif ication? (Electrode,TIG,MIG/MAG,UP)
Is the consumable( Electrodes, wire, flux ) according to specification? (AWS,EN)
Is the consumable approved by the classification society? (DNV,ABS,BV,GL,LR)Is the grading to standard? ( 3Y H10 for ship quality steel )
Is the approval up to date?
Has the consumable been correctly stored?
Electrodes, wire and f lux must be stored in unopened original containers
15- 25C Max 50% Relative humidity>25C Max 40% Relative humidity
Is there a requirement for re-drying of consumables before use?
Basic and stainless electrodes can for crit ical applications be heated to
300- 350C for 2 hoursDos the welder have the necessary approval for the work at hand?
INSPECTION OF WELDED JOINTS
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INSPEKSJON AV SVEISEARBEID
UNDER SVEISINGEr det krav til forvarming av grunnmaterialet fr sveising?( Ce + Tykkelse)
Kontroller at sveiseparameterne er i henhold til sveiseprosedyren
(polaritet, ampere, vol t etc)
Blir mellomlagstemperaturen overholdt? ( interpas temperature )
Ved flerlags sveis, sjekk rotstrengen for full gjennombrenningInspiser hvert lag fr neste lag ( pse god rengjring mellom lagene)
Er det krav til varmebehanling etter sveising?
ETTER SVEISING
Kontroller sveisens overflate for sprekker, porer, slagginnslutninger,underkutt samt at endekratere er fylt.
Kontroller dimensjonelle variasjoner ved hjelp av skyvelret
Kontroller A- ml for: Oversveising
Undersveising
Kontroller likebenhet
Kontroller konveksitet
Maks underkutt I henholdtil ASME:
Underkutt dypere en 0,8 mm
og lenger en 6 mm er
uakseptabelt
Underkutt mindre en 0,8 mmmen lenger en 6 mm m
vurderes fra sak t il sak
avhengig av forholdene
Overhyde:1,6 mm for manual sveising
3,2 mm for automatisert
sveisingFlat eller konkav Konveks
Underkutt
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Max undercut according toASME:
Undercut deeper than 0,8
mm and longer than 6 mm
is unacceptable
Undercut less than 0,8 mmbut longer than 6mm must
be evaluated from case to
case
Reinforcement:
1,6 mm for manual welding
3,2 mm for mechanized
weldingFlat or concave Convexity
Undercut
INSPECTION OF WELDED JOINTS
DURING WELDINGIs there a requirement for pre-heating of base material before welding?(Ce + thickness)
Control that the welding parameters are in accordance with the welding
procedure (polarity, amperage, voltage)
Are the interpass temperature requirements followed ?
When doing mult i-layer welding, check that the root run have fullpenetration
Inspect every run before next run ( clean for slag between layers)
Is there a requirement for post weld heat treatment?
AFTER WELDINGInspect the weld surface for cracks, porosity, slag inclusions,
undercut and that end crater is f illed.
Check dimensional variations using a welders gauge
Check that reinforcement is sufficient but not to high
Check equal leg length
Check for convexity
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