Typical application cases I: aircraft engine blades testing

1. Overviews          
Blade is one of aircraft engine main parts, as its function, the work environment of the blade is pretty bad. Blade bears the alternating loads formed by high centrifugal load, aerodynamic load, high temperature and atmospheric temperature difference load and vibration load, compressed air blade is also impacted by the foreign substance from engine inlet, eroded by sand wind sand moisture. Turbine blade is corroded by gases and bears high temperature thermal stress, etc. These factors make blade prone to produce defects such as fatigue cracks. If dismantling detection, it is trouble and waste of time. So in-situ vortex testing technique is one of important means to detect modern engine, it avoids the remove, dismantle and installation of equipment and structure, saves test time and costs.

2. Method of application             
Due to the particularity of engine structure, other NDT methods (such as X-ray, magnetic powder, penetration) are limited in situ test because of technical limitations. For the surface defects, vortex testing is one of the most appropriate method. When testing blade in situ, the surface pollutants do not be cleared up due to the reason of structure. If using ordinary vortex probe, there will be a big lift-off effect. Therefore, our company made a special sensors whose outline design matches the space of tested part, and can easily into equipment to test the edge and surface of blade. The coil of probe is specially designed, its principle is similar to the special probe for welds, and overcome the lift-off effect of vortex.
A principle diagram for special probe
Vortex testing signal diagram
Blade special probe
 Blade special probe
3. Superior characteristic          
Vortex detection in situ has the advantages such as intuitive, reliable, repeatability, and simple and convenient operation, saves test time and maintenance cost. Data can be stored, and have playback, view functions at any time, achieve data traceability.
4. Recommend instruments