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SOLUTIONS: Evaluation of welds Summing up inspection of welded joints. What to look for PRIOR TO WELDING: • Type/state of base material • Joint design • Welding process • Consumables • Welding procedure • Welder’s qualifications

What to do DURING WELDING: • Compare welding parameters with procedure • Inspect each layer before the next What to look for AFTER WELDING: • The final weld result • Size of weld (measuring)

Faults and causes:

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Surface porosity

Excessive speed, rusty or dirty plates, wet electrodes or flux, insufficient flux/gas coverage.

Cold cracks (Hydrogen cracks) Wet electrodes or flux. Insufficient preheating.

Hot cracks

Excessively high current. Insufficient preheat. High impurity level in base material

Slag inclusion Faulty technique.

Wrong electrode size or off-spec welding parameters.

Underfill

Too high welding speed

Undercut

High current,

Insufficient electrode angle. Speed of travel too fast.