MK Welding Multi-GMAW 200 LCD PFC - Page 93

62
EN
2
Porosity - small
cavities or holes
resulting from
gas pockets in
weld metal.
Wrong gas
Check that the correct gas is being
used
Inadequate gas flow or too much gas
flow
Check the gas is connected, check
hoses, gas valve and torch are not
restricted. Set the gas flow
between 10 - 15 l/min flow rate.
Check hoses and fittings for holes,
leaks etc .Protect the welding zone
from wind and drafts
Moisture on the base metal
Remove all moisture from base
metal before welding
Contaminated base metal
Remove materials like paint,
grease, oil, and dirt, including mill
scale from base metal
Contaminated mig wire
Use clean dry rust free wire. Do
not lubricate the wire with oil,
grease etc
Gas nozzle clogged with spatter,
worn or out of shape
Clean or replace the gas nozzle
Missing or damaged gas diffuser
Replace the gas diffuser
Mig torch euro connect o-ring
missing or damaged
Check and replace the o-ring
3
Wire stubbing
during welding
Holding the torch too far away
Bring the torch closer to the work
and maintain stick out of 5-10mm
Welding voltage set too low
Increase the voltage
Wire Speed set too high
Decrease the wire feed speed
4
Lack of Fusion −
failure of weld
metal to fuse
completely with
base metal or a
proceeding weld
bead.
Contaminated base metal
Remove materials like paint,
grease, oil, and dirt, including mill
scale from base metal
Not enough heat input
Select a higher voltage range and
/or adjust the wire speed to suit
Improper welding technique
Keep the arc at the leading edge of
the weld pool.
Gun angle to work should be
between 5 & 15° Direct the arc at
the weld joint
Adjust work angle or widen
groove to access bottom during
welding
Momentarily hold arc on side
walls if using weaving technique
5
Excessive
Penetration −
weld metal
Too much heat
Select a lower voltage range and
/or adjust the wire speed to suit
Increase travel speed