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17.0 WELDING
DISCONTINUITIES AND
DEFECTS
• Defect: The wire pushes the torch back from the
workpiece.
Cause: Excessive wire speed.
• Defect: The wire sticks on the contact tip.
Cause: Low wire feeding.
• Defect: Excessive welding spatters
Cause: Erratic wire feeding, improper torch position
(too inclined)
• Defect: Arc is unstable
Cause: Low voltage, erratic wire feeding, inadequate
gas flow rate.
• Defect: Inadequate penetration.
Cause: Welding current too low, excessive travel
speed, torch travel direction should be reversed.
• Defect: Cracking
Cause: Base material dirty, welding current too low,
excessive welding voltage, rust on the electrode wire.
• Defect: Porosity
Cause: Cylinder of shielding gas empty, leaky gas
hoses, wrong adjustment of gas flow rate.
