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SOLUTIONS: Evaluation of welds

2.10

Excessive penetration

Lack of penetration

The root pass in multi pass grooves are especially susceptible to cracking

Groove welds are prone to undercut along the edges, increasing the risk of trapping slag when the next pass is made

Slag trapping may also be caused by a convex bead

Check that welding parameters are according to procedure with regard to type of current, polarity, amperage, type of consumable etc.

During welding

Assuming the preliminary requirements are met, the productive inspection will take place while the weld is being done. Examination of a weld bead and the end crater may to a competent inspector reveal quality deficiencies such as cracks, inadequate penetration, and gas and slag inclusions.

On simple welds, inspection of a specimen at the beginning of the

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operation and periodically as the work progresses may be adequate. When more than one layer of filler metal is deposited, however, it may be desirable to inspect each layer before the next.

The root pass in a multipass weld is the most critical one with regard to weld soundness.

Check that the welding parameters match the parameters laid down in the approved welding procedure.