NDT inspection is the industry standard for inspection of aircraft bodies, propellers and components. NDT sertification in the aviation industry requires courses, extensive training and a large amount of practice hours.
Norrønafly has more than 40 years of experience in the field of NDT and can perform many different inspections. All of our inspectors are certified in accordance with European Standard EN4179. Specialised services include, but not limited to:
- Eddy Current, Conductivity testing
- Ultrasonic, Conventional and Phased array, Bond testing
- Fluorecent Penetrant
- Magnetic particle, fixed bench, portable Yoke
We use equipment from major manufactures such as GE (Hocking), Olympus (Omniscan), Chemetall, Britemor and Magnaflux
Alternating electrical current is passed through a coil producing a magnetic field. When the coil is placed near a conductive material, the changing magnetic field induces current flow in the material. These currents travel in closed loops and are called eddy currents. Eddy currents produce their own magnetic field so it is possible to measure and find flaws and characterize conductivity, permeability, and dimensional features.
Used to detect surface and near-surface flaws in conductive materials, such as the metals. Eddy current inspection is also used to sort materials based on electrical conductivity and magnetic permeability.
- Detects surface and near surface defects.
- Method can be used for more than flaw detection.
- Minimum part preparation is required.
- Only conductive materials can be inspected.
- Ferromagnetic materials require special treatment to address magnetic permeability.
- Depth of penetration is limited.
- Skill and training required is more extensive than other techniques.
- Surface finish and roughness may interfere.
- Reference standards are needed for setup.
High frequency sound waves are sent into a material by use of a transducer. The sound waves travel through the material and are received by the same transducer or a second transducer. The amount of energy transmitted or received and the time the signal is received are analyzed to determine the presence of flaws. Changes in material thickness, and changes in material properties can also be measured.
Used to locate surface and subsurface defects in many materials including metals, composite and plastics. Ultrasonic inspection is also used to measure the thickness of materials and otherwise characterize properties of material based on sound velocity and attenuation measurements.
- Depth of penetration for flaw detection or measurement is superior to other methods.
- Only single sided access is required.
- Provides distance information.
- Minimum part preparation is required.
- Method can be used for much more than just flaw detection.
- Surface must be accessible to probe and couplant.
- Skill and training required is more extensive than other technique.
- Surface finish and roughness can interfere with inspection.
- Thin parts may be difficult to inspect.
- Linear defects oriented parallel to the sound beam can go undetected.
- Reference standards are often needed.
Penetrant solution is applied to the surface of a precleaned component. The liquid is pulled into surface-breaking defects by capillary action. Excess penetrant material is carefully cleaned from the surface. A developer is applied to pull the trapped penetrant back to the surface where it is spread out and forms an indication. The indication is much easier to see than the actual defect.
Used to locate cracks, porosity, and other defects that break the surface of a material. Liquid penetrant testing is used on most nonporous materials.
- Parts with complex geometry are routinely inspected.
- Indications are produced directly on surface of the part providing a visual image of the discontinuity.
- Equipment investment is minimal.
- Detects only surface breaking defects.
- Surface preparation is critical as contaminants can mask defects.
- Requires a relatively smooth and nonporous surface.
- Post cleaning is necessary to remove paints, sealing, chemicals and more.
- Requires multiple operations under controlled conditions.
- Chemical handling precautions are necessary (toxicity, fire, waste).
Magnetic Particle Testing
A magnetic field is established in a component made from ferromagnetic material. The magnetic lines of force travel through the material, and exit and re-enter the material at the poles. Defects such as crack or voids cannot support as much flux, and force some of the flux outside of the part. Magnetic particles distributed over the component will be attracted to areas of flux leakage and produce a visible indication
Used to inspect ferromagnetic materials (those that can be magnetized) for defects that result in a transition in the magnetic permeability of a material. Magnetic particle inspection can detect surface and near surface defects.
- Can detect surface and subsurface flaws.
- Surface preparation is less critical than it is in penetrant inspection.
- Magnetic particle indications are produced directly on the surface of the part and form an image of the discontinuity.