NDT Discontinuity Interpretation and Evaluation 2

Question 1

A weld radiograph shows a dark, elongated indication with fuzzy edges running parallel to the weld axis. This is most likely:

Accepted Answer

Incomplete fusion

Answer

Incomplete fusion appears as an elongated dark line with fuzzy or diffuse edges parallel to the weld joint.

Question 2

In ultrasonic testing, a discontinuity signal that appears at half the material thickness and disappears when the probe is angled slightly is most characteristic of:

Accepted Answer

Lamination

Answer

Laminations are planar discontinuities parallel to the plate surface that produce signals at mid-thickness and are highly angle-sensitive.

Question 3

During magnetic particle testing, a tight linear indication is found perpendicular to the applied field. The inspector should:

Accepted Answer

Re-inspect with field perpendicular to the indication

Answer

An indication perpendicular to the field may be a false indication; rotating the field 90° confirms whether it is a true discontinuity.

Question 4

A liquid penetrant indication that bleeds out rapidly and becomes large and diffuse most likely indicates:

Accepted Answer

A gross surface porosity or large opening

Answer

Rapid, diffuse bleed-out is characteristic of wide, open discontinuities such as gross porosity that hold large volumes of penetrant.

Question 5

When evaluating a radiograph, a bright (white) round spot surrounded by a dark halo is most likely:

Accepted Answer

Tungsten inclusion

Answer

Tungsten inclusions appear as bright white dense spots because tungsten is more radiographically opaque than the surrounding weld metal.

NDT - Non-Destructive Testing Practice Test

NDT - Non-Destructive Testing Practice Test

NDT Discontinuity Interpretation and Evaluation 2