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SOLUTIONS: Evaluation of welds Inspection of welded joints Inspection indicates whether the prescribed standard of quality has been met. This function may be the responsibility of the superintendent or other representative of the ship owner:

2.10

Visual inspection from start to finish Visual inspection is the best buy in Non Destructive Testing (NDT) but it must take place constantly, prior to, during and after welding. In a sense, everyone involved in the job, as well as the appointed inspector, participate in visual inspection. A conscientious worker does not knowingly pass on work in which he recognises discontinuities of his own making. Nevertheless, it is usually desirable that someone is assigned the responsibility for quality checking each operation. In addition to good eyesight and proper light, the tools for visual inspection are simple – a pocket rule, a weld-size gauge, a magnifying glass, and sometimes a straight edge and square for determining straightness, alignment, and perpendicularity.

Inspector’s tools: Magnifying glass, Torch, Ruler and Welders gauge

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Prior to welding

Visual inspection should begin before the first arc is struck. The materials should be examined to see if they meet specifications for quality, type, size, cleanliness, and freedom from discontinuities. Foreign matter

Check Material Certificate

– grease, paint, oil, oxide film, heavy scale – that should be detrimental to the weld shall be removed. The pieces to be joined should be checked for straightness, flatness, and dimensions. Warped, bent, improperly cut or damaged pieces should be ordered for repair or rejected. Alignment and fixtures should be scrutinised. Joint preparation should be checked. Often little more than a passing glance is required as a preliminary inspection, but, despite its almost casual nature, it can be a significant factor in weld quality. A good joint design will provide access for the welder, adequate root opening to permit full fused penetration and correct groove angle to minimise volume of weld metal. The joint preparation must be correct before welding is started, not only to meet the specifications, but also to give assurance of weld quality.