API 510 Inspection Methods & Nondestructive Testing 3

Question 1

During phased array ultrasonic testing (PAUT) of a pressure vessel weld, what does the S-scan (sectorial scan) display show?

Accepted Answer

A cross-sectional view of the weld using multiple beam angles from a single probe position

Answer

The S-scan (sectorial scan) sweeps through multiple angles electronically, displaying a fan-shaped cross-section of the weld in a single probe placement.

Question 2

When performing external visual inspection of a pressure vessel, an inspector observes blistering of the paint coating near a weld. What should this observation prompt?

Accepted Answer

Further NDE such as UT or MT to evaluate for possible cracking or corrosion beneath the coating

Answer

Blistering near welds can indicate disbonded coating over corrosion or stress corrosion cracking, warranting follow-up NDE.

Question 3

A pressure vessel inspector uses acoustic emission (AE) testing during a hydrostatic pressure test. What does a cluster of AE activity at a specific location most likely indicate?

Accepted Answer

Active crack growth or significant stress concentration at that location

Answer

Clustered AE signals at a specific location suggest active crack propagation or significant plastic deformation, requiring follow-up NDE.

Question 4

When evaluating a pressure vessel shell with shear-wave UT, the inspector sets refracted angle at 45°. In which material condition would a 60° probe be preferred over 45°?

Accepted Answer

When the weld has a steep bevel or narrow groove geometry where 45° beams cannot adequately illuminate the fusion line

Answer

Steep-bevel narrow welds are better interrogated with a 60° beam that can more effectively sweep the near-vertical fusion faces.

Question 5

Under API 510, which condition requires an inspector to recommend a fitness-for-service (FFS) assessment rather than routine repair?

Accepted Answer

A crack-like flaw detected by UT in a high-cycle fatigue service vessel

Answer

Crack-like flaws in fatigue service require API 579 FFS assessment to determine remaining life and acceptability before continuing operation.

(API 510) Certified Pressure Vessel Inspector Practice Test

(API 510) Certified Pressure Vessel Inspector Practice Test

API 510 Inspection Methods & Nondestructive Testing 3