Causes and Cures of Common Welding · PDF fileCauses and Cures of Common Welding defects...
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Causes and Cures of Common Welding defects Welding Type worm hole Defect: Blow Hole worm hole blow 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 or insufficient gas shielding. 5.Welding in the windy surrounding without trailer shield. Welding Type 1.Wet, unclean or damaged electrode. 2.Base metal surface covered with oil, rust, etc. 3.Over travelling speed. 4.Over currents 5.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 store electrode. 2.Properly clean base metal prior 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 metal prior to welding. 2.Properly maintain and store wire and flux. 3.Choose wire size properly and proceed spot welding correctly. 4.Maintain proper arc length and gas flow rate. 5.Add trailer shield. 188
Transcript of Causes and Cures of Common Welding · PDF fileCauses and Cures of Common Welding defects...
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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