Elettro CF MIG 290 Instruction Manual page 9

CAUSES • Electrode defective (rusted surface)
• Missing shield
- low gas flow
- flow gauge defective
- regulator frosted due to no
of the CO
- defective solenoid valve
- contact tip clogged with sp
- gas outlet holes clogged
- air drafts in welding
2 DEFECT - Shrinkage cracks .
CAUSES • Wire or workpiec
• Bead too small.
• Bead too concave.
• Bead too deeply
3 DEFECT - Side cuts .
CAUSES
• Welding pass done too quickly
• Low current and high arc voltages.
4 DEFECT - Excessive sprayin .
CAUSES • Voltage too high.
• Insufficient inductance.
• No preheating o
gas
5 MAINTAINING THE SYSTEM
• Shielding gas nozzle.
This nozzle must be periodically cleaned to rem
weld spatter. Rep lace if distorted or squashed.
• Contact tip.
Only a good contact between this contact tip and the
wire can ensure a stable arc and optimum current
must therefore observe the following
output; you
precautions:
A) The contact tip hole
and oxidation (rust).
B) Weld spatter sticks more easily af
sessions, blocking the wire flow.
C) The tip must therefore be
and replaced if necessary.
D) The contact tip must always be firmly screwed
onto the torch body. The thermal cycles to which
the torch is subjected can cause it to loosen, thus
heating the torch body an
wire to advan ce unevenly.
• Wire liner.
This is an important part that must be checked often,
because the wire may deposit copper dust or tiny
shavings. Clean it periodically a
lines, using dry compressed air.
The liners are subjected to constant wear and tear,
ust be replaced after a certain
and therefore m
amount of time.
• Gearmotor group.
Periodically clean the set of feeder rollers, to remove
any rust or metal residue left by the coils. You must
periodically check the entire wire feeder
h asp, wire guide rollers, liner and contact tip.
ing gas due to:
preheating
protection gas
2
atter
area.
e dirty or rusted.
penetrated.
g
f the CO protection
2
must be kept free of grime
ter long welding
cleaned more often,
d tip and causing the
long with the gas
ove
group:
8