
9-11.  Troubleshooting − Lack Of Penetration
| 
 | 
 | 
 | 
 | 
 | Lack Of Penetration − shallow | 
| 
 | 
 | 
 | 
 | 
 | |
| 
 | 
 | 
 | 
 | 
 | fusion between weld metal and | 
| 
 | 
 | 
 | |||
| 
 | 
 | 
 | 
 | 
 | base metal. | 
| Lack of Penetration | Good Penetration | ||||
| 
 | 
 | 
 | 
 | 
 | |
| 
 | 
 | 
 | 
 | ||
| Possible Causes | 
 | 
 | Corrective Actions | ||
| 
 | 
 | 
 | |||
| Improper joint preparation. | 
 | Material too thick. Joint preparation and design must provide access to bottom of groove while | |||
| 
 | 
 | 
 | 
 | maintaining proper welding wire extension and arc characteristics. | |
| 
 | 
 | 
 | |||
| Improper weld technique. | 
 | Maintain normal gun angle of 0 to 15 degrees to achieve maximum penetration. | |||
| 
 | Keep arc on leading edge of weld puddle. | 
| 
 | 
 | 
| 
 | Be sure welding wire extends not more than 1/2 in. (13 mm) beyond nozzle. | 
| 
 | 
 | 
| Insufficient heat input. | Select higher wire feed speed and/or select higher voltage range. | 
| 
 | 
 | 
| 
 | Reduce travel speed. | 
| 
 | 
 | 
| Incorrect polarity. | Check polarity required by welding wire, and change to correct polarity at welding power source. | 
9-12.  Troubleshooting − Incomplete Fusion
| 
 | 
 | 
 | 
 | Incomplete Fusion − failure of weld metal to fuse completely with | 
| 
 | 
 | 
 | 
 | base metal or a preceeding weld bead. | 
| 
 | 
 | 
 | 
 | |
| 
 | 
 | 
 | 
 | |
| 
 | 
 | 
 | 
 | |
| 
 | 
 | 
 | 
 | |
| Possible Causes | 
 | 
 | Corrective Actions | |
| 
 | 
 | 
 | ||
| Workpiece dirty. | 
 | Remove all grease, oil, moisture, rust, paint, undercoating, and dirt from work surface before | ||
| 
 | 
 | 
 | welding. | |
| 
 | 
 | 
 | ||
| Insufficient heat input. | 
 | Select higher voltage range and/or adjust wire feed speed. | ||
| 
 | 
 | 
 | ||
| Improper welding technique. | 
 | Place stringer bead in proper location(s) at joint during welding. | ||
| 
 | 
 | 
 | 
 | |
| 
 | 
 | 
 | Adjust work angle or widen groove to access bottom during welding. | |
| 
 | 
 | 
 | 
 | |
| 
 | 
 | 
 | Momentarily hold arc on groove side walls when using weaving technique. | |
| 
 | 
 | 
 | 
 | |
| 
 | 
 | 
 | Keep arc on leading edge of weld puddle. | |
| 
 | 
 | 
 | 
 | |
| 
 | 
 | 
 | Use correct gun angle of 0 to 15 degrees. | |
| 
 | 
 | 
 | 
 | 
 | 
9-13.  Troubleshooting − Burn-Through 
| Possible Causes | Corrective Actions | 
| 
 | 
 | 
| Excessive heat input. | Select lower voltage range and reduce wire feed speed. | 
| 
 | 
 | 
| 
 | Increase and/or maintain steady travel speed. | 
| 
 | 
 | 
| 
 | 
 |