NDT Ultrasonic Testing 2

Question 1

What is the primary purpose of a couplant in ultrasonic testing?

Accepted Answer

To eliminate the air gap between the transducer and test material

Answer

Couplants fill the air gap between the transducer and material surface, enabling efficient transfer of ultrasonic energy since air is a poor acoustic conductor.

Question 2

In ultrasonic testing, what does 'beam spread' refer to?

Accepted Answer

The divergence of the ultrasonic beam as it travels through a material

Answer

Beam spread is the natural divergence of an ultrasonic beam as it travels away from the transducer, which affects lateral resolution and coverage area.

Question 3

Which ultrasonic testing method uses two separate transducers — one for sending and one for receiving?

Accepted Answer

Pitch-catch technique

Answer

The pitch-catch (or through-transmission) technique uses separate transmitter and receiver transducers, allowing detection of flaws that might not produce strong reflections.

Question 4

What is the 'near field' (Fresnel zone) in ultrasonic testing?

Accepted Answer

The region close to the transducer where sound pressure varies irregularly

Answer

The near field (Fresnel zone) is the region close to the transducer face where constructive and destructive interference cause irregular sound pressure variations.

Question 5

When performing angle beam UT on a weld, what is the 'skip distance'?

Accepted Answer

The surface distance traveled for one complete V-path (down and back up)

Answer

Skip distance is the surface distance covered in one full V-path of an angle beam, from entry point to where the beam returns to the surface after reflecting off the back wall.

NDT - Non-Destructive Testing Practice Test

NDT - Non-Destructive Testing Practice Test

NDT Ultrasonic Testing 2