NDT UT in Air crafts

NDT UT in Air crafts

• 1.
  NDT in Aircraft Submitted by OjesSai K-5870
• 2.
  NDT- UT • Ultrasonictesting uses pulses of high-frequency sound energy to detect surface and subsurface cracks and other defects. These pulses come from a transducer or probe, which a technician manually moves over the surface of the component under inspection. The probe emits ultrasonic waves into the material at precise intervals and a set angle; when a sound wave encounters a defect, some of that energy is reflected like an echo. • A probe sends a sound wave into a test material. There are two indications, one from the initial pulse of the probe, and the second due to the back-wall echo. A defect creates the third indication and simultaneously reduces the amplitude of the back-wall indication. The depth of the defect is determined by the ratio D/Ep
• 3.
  UT methods usedin aircraft inspections • A conventional or standard UT probe is capable of generating and receiving a single ultrasonic sound wave. The focal point and angle of the beam are fixed, which can make it more difficult to locate and visualize flaws especially in components with complex geometries like engine fan blades. The use of a custom-shaped probe can help ensure the accuracy of such inspections. • Phased-array UT is an advanced inspection method that uses multiple individual elements (typically from 16 to 64) in a single probe. By exciting each element in a controlled manner, a phased-array UT instrument can produce a precise beam shape and generate two and three-dimensional views of a flaw with greater speed and accuracy. This is a significant advantage for inspection of complex geometries in order to improve probability of detection (POD) and to better characterize potential indications.