Saf-Fro PRESTO 300MV, Instructions For Use Safety And Maintenance

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EN-13
EN
TROUBLESHOOTING
8 - TROUBLESHOOTING
This chart will assist you in resolving common problems you may encounter in welding; for electrical faults see (Tab.3 – Section 6.2.)
PROBLEM POSSIBLE CAUSES CORRECTIVE ACTIONS
Porosity:
small cavities or holes resulting from gas
pockets in weld metal.
Arc length too long. Reduce arc length.
Damp electrode. Use dry electrode.
Work piece dirty. Remove all grease, oil, moisture, rust, paint,
coating and slag from work surface before
welding.
Excessive spatter:
scattering of molten metal particles that cool to
solid form near weld bead.
Amperage too high for electrode. Decrease amperage or select larger electrode.
Arc length too long or voltage too high. Reduce arc length or voltage.
Incomplete Fusion:
failure of weld metal to fuse completely with
base metal or a proceeding weld bead.
)† ! Increase amperage. Select large electrode and
increase amperage.
Improper welding technique. 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.
Work piece dirty. Remove all grease, oil, moisture, rust, paint,
coating and slag from work surface before
welding.
Lack of penetration:
shallow fusion between weld metal and base
metal.
Improper joint preparation. Material too thick. Joint preparation and design
must provide access to bottom of groove.
Improper weld technique. Keep arc on leading edge of weld puddle.
)† ! Increase amperage. Select large electrode and
increase amperage.
Reduce travel speed.
Excessive penetration:
weld metal melting through base metal and
hanging underneath weld.
Excessive heat input. Select lower amperage. Use smaller electrode.
Increase and maintain steady travel speed.
Waviness of bead:
weld metal that is not parallel and does not
cover joint formed by base metal.
Unsteady hand. Use two hands. Practice technique.
Distortion:
contraction of weld metal during welding that
forces base metal to move.
Excessive heat input. Use clamps to hold base metal in position.
Make tack weld along joint before starting
welding operation.
Select lower amperage for electrode.
Increase travel speed.
Weld in small segments and allow cooling
between welds.