Weld Defects

1. Weld Defects What causes them and how to prevent them

2. Lack Of Fusion • This is where the new weld metal and the base metal are not fused or bonded together. • This can be on the outer edges of the weld bead where it is easily seen, or it can be beneath the weld bead and cannot be seen.

3. What Causes Lack of Fusion? • Possible Causes: • “Cold” Welding Procedures • Travel Speed Too Slow • Travel Speed Too Fast • Possible Cures: • Increase Current • Use Proper Travel Speed

4. Undercut • This is where the area at the toe/edge of the weld is cut in lower than the surface of the base metal

5. Possible causes: • Too high machine setting • Improper rod angle • Arc length too long • Ways to minimize undercut: • Shorten arc length • Use correct arc length • Lower machine setting

6. Porosity • This is tiny holes in the weld. It can resemble a sponge and it weakens a weld.

7. Porosity • Common causes : • Arc length too long • Base metal not cleaned/impurities • Electrode contamination/moisture • Solutions for porosity: • Clean base metal • Shorten arc length • Use good dry electrodes

8. Overlap • This is where the edges of the weld bead is not fused to the base metal. It appears as if the weld is just sitting on top of the metal

9. Overlap • Common causes: • Travel speed too slow • Welding machine setting too low • Possible solutions: • Use correct machine setting • Increase travel speed

10. Slag Inclusions • These are areas where the slag and/or flux may be trapped in the weld or between the weld bead and the base metal.

11. Slag Inclusions • Common causes: • Arc length too long • Improper welding technique • Possible solutions: • Shorten arc length • Use proper welding technique/correct rod angle