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How can lack of fusion defects be prevented?


Frequently Asked Questions

  • use a sufficiently wide joint preparation
  • select welding parameters (high current level, short arc length, not too high a welding speed) to promote penetration into the joint side wall without causing flooding
  • ensure the electrode/gun angle and manipulation technique will give adequate side wall fusion
  • use weaving and dwell to improve side wall fusion providing there are no heat input restrictions
  • if arc blow occurs, reposition the current return, use AC (in MMA [SMA] welding) or demagnetise the steel

For more extensive information on lack of fusion defects, see Job Knowledge for Welders 41 - Weld defects/imperfections in welds - lack of sidewall and inter-run fusion

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