Causes and Cures of Common Welding defects

Welding Type

worm hole

Defect: Blow Hole

worm holeblow hole

Why What to Do

SMAW

CO2/MAG

1.Unclean base metal surface.

2.Rusted wire or wet flux.

3.Improper spot welding or wire.

4.Excessively long arc length orinsufficient gas shielding.

5.Welding in the windy surroundingwithout trailer shield.

Welding Type

1.Wet, unclean or damagedelectrode.

2.Base metal surface coveredwith oil, rust, etc.

3.Over travelling speed.4.Over currents5.Excessively long or short arc

length.6.Too thick base-metal or too

fast cooling rate.

Why What to Do

SMAW

1.Properly maintain and storeelectrode.

2.Properly clean base metalprior to welding.

3.Reduce travel speed.4.Use proper welding current.5.Maintain proper arc length.

6.Proceed proper pre-heating.

CO2/MAG

1.Properly clean base metalprior to welding.

2.Properly maintain and storewire and flux.

3.Choose wire size properlyand proceed spot weldingcorrectly.

4.Maintain proper arc lengthand gas flow rate.

5.Add trailer shield.

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