VISUAL INSPECTION OF WELDING

VISUAL INSPECTION OF WELDING

INTRODUCTION
Inspection starts with examination of the material prior to fabrication, scabs, seams, scale or other harmful surface conditions may be detected in visual inspection.

The inspector should check the following :

Weld preparation, dimensions and finish.
Clearance dimensions of backing strips.
Alignment and fit up to the pieces being welded.
Verification of cleanliness.

Visual Inspection During Welding
Visual inspection checks details of the work while welding is in progress. Among the details to be checked are :

Welding process.
Cleaning.
Preheat and inter pass temperature.
Joint preparation.
Filler metal.
Flux or shielding gas.
Chipping, grinding, or gouging.
Post heating temperature and time.

Visual Inspection After Welding
Visual inspection is useful for finished-product verification of such items as :

Profile irregularities of the weldment.
Conformity to drawing requirements.
Acceptability of welds with regard to appearance (eg: surface roughness).
The presence of unfilled undercut, overlaps and cracks.
Evidence of mishandling from center punch or other inspection markings or excessive grinding.

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