NDT Visual Testing Fundamentals 4

Question 1

During visual inspection of a pressure vessel, an inspector finds a 'blister' on the inner surface. This most likely indicates:

Accepted Answer

Hydrogen-induced blistering from wet H₂S service

Answer

Blisters on internal pressure vessel surfaces in sour service are classic indicators of hydrogen-induced cracking (HIC) where hydrogen diffuses into the steel.

Question 2

Which magnification level is typically the MAXIMUM recommended for unaided visual testing without an optical aid?

Accepted Answer

1x (unaided eye)

Answer

Unaided direct visual testing uses 1x magnification (no optical aid); any magnification above 1x requires an approved optical aid.

Question 3

What is the significance of a 'witness mark' left on a component during fabrication visual inspection?

Accepted Answer

It documents that a specific inspection checkpoint was completed

Answer

Witness marks (stamps or paint marks) confirm that an authorized inspector examined and accepted the component at a defined checkpoint.

Question 4

For weld visual inspection, 'overlap' (also called cold lap) is best described as:

Accepted Answer

Weld metal that protrudes beyond the joint without fusing to the base metal

Answer

Overlap is an imperfection where weld metal flows beyond the toe of the weld and lies on the base metal surface without metallurgical fusion.

Question 5

When documenting a VT finding, which piece of information is LEAST critical to include in the inspection report?

Accepted Answer

The inspector's shift supervisor's home address

Answer

A supervisor's personal address is irrelevant to inspection documentation; location, dimensions, inspector ID, and date are all required fields.

NDT - Non-Destructive Testing Practice Test

NDT - Non-Destructive Testing Practice Test

NDT Visual Testing Fundamentals 4