Miller Blue Star 145DX Manual Del Proprietário página 50

13-12. Weld Test
2 To 3 in.
(51-76 mm)
1/4 in.
(6.4 mm)
13-13. Troubleshooting
Possible Causes
Arc length too long.
Damp electrode.
Workpiece dirty.
Possible Causes
Amperage too high for electrode.
Arc length too long or voltage too high.
Possible Causes
Insufficient heat input.
Improper welding technique.
Workpiece dirty.
OM-248 551 Page 46
3
2 To 3 in.
(51-76 mm)
2
2
1
Porosity − small cavities or holes resulting from gas pockets in weld metal.
Corrective Actions
Reduce arc length.
Use dry electrode.
Remove all grease, oil, moisture, rust, paint, coatings, slag, and dirt from work surface before
welding.
Excessive Spatter − scattering of molten metal particles that cool to solid form near weld bead.
Corrective Actions
Decrease amperage or select larger electrode.
Reduce arc length or voltage.
Incomplete Fusion − failure of weld metal to fuse completely with base metal or a preceeding
weld bead.
Corrective Actions
Increase amperage. Select larger electrode and increase amperage.
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.
Remove all grease, oil, moisture, rust, paint, coatings, slag, and dirt from work surface before
welding.
1 Vise
2 Weld Joint
3 Hammer
Strike weld joint in direction shown.
A good weld bends over but does
not break.
3
1
S-0057-B