CIGWELD weldskill 150 - Page 48

WELDSKILL 100, 135, 150 MIG
5-4
Service
Welding Problems
FAULT CAUSE REMEDY
1
Undercut A Welding arc voltage too
high.
A Reduce voltage by reducing the Output Voltage
Control Switch positions or turn the Wirespeed
control knob anticlockwise.
B Incorrect torch angle B Adjust angle
C Excessive heat input C Increase the torch travel speed or reduce welding
current by reducing the Output Voltage Control
Switch positions and turn the Wirespeed control
knob anti-clockwise.
2
Lack of penetration A Welding current too low A Increase welding current by increasing the
Wirespeed control knob clockwise and increasing
Output Voltage Control Switch positions.
B Joint preparation too narrow
or gap too tight
B Increase joint angle or gap
C Shielding gas incorrect C Change to a gas which gives higher penetration
3
Lack of fusion Arc voltage to low Increase Arc voltage by increasing the Output
Voltage Control Switch positions.
4
Excessive spatter A Arc voltage too high A Lower voltage by reducing the Output Voltage
Control Switch positions or turn the Wirespeed
control knob anti-clockwise.
B Arc voltage too low B Raise voltage by increasing the Output Voltage
Control Switches or turn the Wirespeed control
knob clockwise.
5
Irregular weld shape A Incorrect voltage and
current settings. Convex,
Arc voltage too low
Concave, voltage too high
A Adjust voltage and current by adjusting the
Output Voltage Control Switch positions and the
Wirespeed control knob.
B Wire is wandering B Replace contact tip
C Incorrect shielding gas C Check gas selection
D Insufficient or excessive
heat input
D Adjust the Wirespeed control knob or the Output
Voltage Control Switch.
6
Arc does not have a
crisp sound that short
arc exhibits when the
wirefeed speed and
voltage are adjusted
correctly
The MIG torch has been
connected to the wrong
voltage polarity.
Connect the MIG torch to the positive welding
terminal (+) for solid wires and gas shielded
flux cored wires. Refer to Section 3.10 Polarity
Changeover.
7
Weld cracking A Weld beads too small A Decrease torch travel speed
B Weld penetration narrow
and deep
B Reduce current and voltage and increase the MIG
Torch travel speed or select a lower penetration
shielding gas.
C Excessive weld stresses C Increase weld metal strength or revise design
D Excessive voltage D Decrease voltage by reducing the Output Voltage
Control Switch.
E Cooling rate too fast E Slow the cooling rate by preheating part to be
welded or cool slowly.
8
Cold weld puddle A Faulty rectifier unit A Have an Accredited CIGWELD Service Provider
test then replace the faulty component.
B Loss of a phase in the Mains
supply voltage.
B Check mains power
C Loose welding cable
connection.
C Check all welding cable connections.
D Low Mains supply voltage D Contact supply authority
Table 5-3