Non Destructive Testing is used across all areas of Marine inspection from metallic based structures through to composite components and structures which include carbon fibre, glass fibre monolithic and cored laminates. There are two key stages to when inspection procedures take place; during manufacture and whilst in-service. In-service sea going vessels are generally subject to regular inspections, of which NDT can form an important part.
During manufacture welded joints are inspected using Flaw Detectors or Phased Array & ToFD systems to ensure that they are defect free. Similar techniques are used to inspect key components such as, boilers, shafts and propellers.
Aluminium hulled vessels generally are built for minimum weight, so have a controlled thickness. Thickness gauges are used to ensure that the thickness of plating is adequate. Where welds have been dressed by grinding Dye Penetrant visual inspection is usually required.
Thickness surveys are carried out, using an A-Scan thickness gauge such as the CT-Gage DL+ or Betagage. These instruments allow for coating rejection and differentiation of plate inclusions from wall loss.
For marine composite inspection including scanning glue joints, monolithic panels and skin-to-core interfaces in sandwich panels the Rapidscan 2 together with Array WheelProbes provide clear and detailed C-scan images, identifying any anomalies accurately using an efficient scanning speed.
Ben Pierrepont of Pierrepont Analysis using the Rapidscan 2 and Array WheelProbe for marine composite inspection.