WELDING DEFECTS & REMEDIAL MEASURES
Defect
Remedial Measures
NDE
MT/PT + RT/UT
Lack Of Fusion
Defective
weld
shall
be
removed
completely by gouging and/or grinding and
the resulting cavity to be properly prepared
for welding. Use moderate welding voltage
& current according to the base metal
thickness and re-weld the defective area
with moderate speed.
Gouge or ground from the weld face to
remove entire weld down to the root.
Select electrode according to welding
groove size and re-weld the defective area
with enough current to get the desired
penetration.
MT/PT + RT/UT
Lack Of Penetration
Cracking
Defective
weld
shall
be
removed
completely by gouging and/or grinding and
the resulting cavity to be properly prepared
for welding. Pre-heat the defective area
with gas torch. Ensure a sound root pass
and check for any flaws by PT. Complete
the welding.
Defective
weld
shall
be
removed
completely by gouging and/or grinding and
the resulting cavity to be properly prepared
for welding. Re-welding of the defective
area to be carried out.
MT/PT + RT/UT
MT/PT + RT/UT
Weld Discontinuity
Defective
weld
shall
be
removed
completely by gouging and/or grinding and
the resulting cavity to be properly prepared
for welding. Re-welding of the defective
area to be carried out.
MT/PT + RT/UT
Crater Pinhole
Arc Strikes discovered in or adjacent to
welded joints shall be repaired by grinding
and/or welding. Arc strikes repaired by
welding shall be ground flush with the
plate.
VT,MT/PT
Arc Strikes
Porosity
Defective weld shall be removed completely
by gouging and/or grinding and the resulting
cavity to be properly prepared for welding
including thorough cleaning. During welding
allow sufficient puddling time for gases to
escape. At the same time hold a longer and
stable arc. Ensure usage of proper current &
electrodes according to the base metal.
Existing weld undercut shall be repaired by
additional weld metal with moderate
current and slow weld speed. Avoid usage
of large electrodes.
MT/PT + RT/UT
MT/PT + RT/UT
Undercut
Excessive Reinforcement
Generally it is not necessary to remove the
existing weld reinforcement. However if it
hinders the movement of floating roof with
flexible seals, consideration shall be given
to repairing the excessive reinforcement by
grinding.
VT
MT- Magnetic Particle Test, PT- Penetrant Test, UT- Ultrasonic Test, RT- Radiography Test, VT- Visual
Test
Burn-through
Defective
weld
shall
be
removed
completely by gouging and/or grinding and
the resulting cavity to be properly prepared
for welding. Weld deposition to be carried
out with proper electrode and appropriate
current
settings
depending
on
the
thickness of the base metal.
MT/PT + RT/UT
MT- Magnetic Particle Test, PT- Penetrant Test, UT- Ultrasonic Test, RT- Radiography Test, VT- Visual
Test
