Marine Results’ Non Destructive Testing (NDT) service is available for all marine composite components and structures including carbon fibre, glass fibre, monolithic and cored laminates.
Inspections are carried out using aerospace grade flaw detection equipment following aerospace inspection procedures for metallic and composite monolithic and cored structures. The equipment can detect disbonds and delaminations and provide evidence of inclusions, porosity and other discontinuities that could affect the performance of materials and components.
The NDT techniques that Marine Results uses can find a range of anomalies and defect types in metallic and composite structures. Examples of production and in-service defects that we have found include:
Voiding and porosity can be indication of poor manufacturing processes or a problem during moulding and curing of the laminate. Evidence of porosity can be detected using conventional ultrasound. In some cases the degree of porosity can be quantified using techniques similar to those employed in the aerospace industry.
Impact damage in monolithic composites can quickly be identified using ultrasonic inspection to detect the extent of the damaged area and evaluate the nature of the damage. This provides important data to the designer and manufacturer so that an effective repair schedule can be formulated.
Skin To Core Delamination
Skin to core delamination is usually detected using acoustic methods which ‘listen’ to the changes in the natural resonance of the structure caused by defects. The specific acoustic method used depends on the type of laminate, its thickness and the type of core.
Whereas cracking or delamination in composites tends to occur in layers parallel to the surface of the laminate, cracks in metallics can occur in any orientation. Marine Results is trained in angle beam ultrasound methods for the detection of cracks in complex parts constructed in steel, stainless and aluminium alloys.
Marine Results boasts a state of the art facility which uses the latest test equipment. This includes Ultrasonic flaw detectors, Ultrasonic phased array equipment, Ultrasonic scanning tank, Mechanical impedance test equipment, Acoustic pitch catch resonance test equipment, Ultrasonic resonance test equipment, Digital tap testing equipment, Shearography, Static dye penetrant station and Portable dye penetrant.
The company has also recently acquired a custom wheel probe which uses rotary array to detect over a large area thus improving time efficiency.
The exact test method used will depend on the nature of the materials to be tested and the level inspection required. The following list includes some of the structures and materials that Marine Results routinely inspect. Please contact us to discuss your requirements in more detail.
Marine inspections built on proven and accepted Aerospace inspection techniques and procedures for composite structures during manufacture and in-service
- Low frequency ultrasound testing (UT) - for Wet lay-up, Nomex, Glass Fibre
- High frequency ultrasound testing (UT) – for Autoclaved laminate, thin skins
- Ultrasound Phased array (PA) – for high and low frequency for large area scanning of masts and hulls – and – for Solid carbon fibre rigging (new technology)
- Acoustic (generically known as bond testing) – for pitch catch resonance, bond testing
- Mechanical – digital tap testing, tap hammer (working to aerospace specifications)
Other technologies if requested:
- Thermal imaging (passive and active)
- Zero degree ultrasound testing (UT) – Corrosion, laminations
- Angle beam ultrasound testing (UT) – Cracks
- Visible and fluorescent dye penetrant testing (PT)
Other technologies if requested:
- Vibration measurement (e.g. IMOCA keel resonance)
NDT Guidance is available in the MCA’s Marine Information Note MIN 417 (M) here.
The A-Scan and B-Scan images to the left can be viewed in larger scale in the gallery.