Ultrasonic Testing for Procedure ISO 17640 & Acceptance Criteriya ISO 11666
Ultrasonic Testing method in which beams of high frequency sound waves that are introduced into the material being tested are used to detect planear and volumetric discontinuities. The sound waves travel through the materials with some attenuation of energy and are reflected at interfaces. The reflected beam is detected and analyzed to define the presence and location of flaws.

Ultrasonic waves are almost completely reflected at metal gas interfaces. Partial reflection occurs at metal liquid or metal solid interfaces, with the specific percentage of reflected energy depending mainly on the ratios of acoustic density of the matter on opposite sides of the interface.

Ultrasonic inspection instruments detect flaws :

  1. Reflection of energy from metal-gas interfaces, metal-liquid interfaces or discontinuities within the metal itself.
  2. Time of transit of a sound wave through the test piece from the entrance point at the sending (transmitting) transducer to the exit point at the receiving transducer, and
  3. Attenuation of the beam of sound waves by absorption and scattering within the test piece.



  1. Ultrasonic Flaw detection requires by experienced technicians.
  2. Technical knowledge is required for the development of Ultrasonic testing procedures. 
  3. Parts that are rough, irregular in shape, very small or thin or not homogenous are difficult to be teste
  4. Couplants are needed to provide effective transfer of ultrasonic wave energy between transducers and parts being tested.
  5. Reference standards are needed, both for calibrating the equipment and for characterizing flaws.

Ultrasonic Inspection:

  1. Ultrasonic Equipments with built-in DGS curves, TGC,  AWS flaw sizing techniques for weld inspections
  2. Transducers suitable for inspections, most sensitive, inspection applications
  3. T-K-Y joints testing 

Ultrasonic Testing-UT Images


Pulse Echo Contact Technique