Visual Testing Fundamentals Flashcards
7 cards from real NDT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Visual Testing Fundamentals flashcards as text
During visual inspection of a pressure vessel, an inspector finds a 'blister' on the inner surface. This most likely indicates:
Answer: Hydrogen-induced blistering from wet H₂S service
Blisters on internal pressure vessel surfaces in sour service are classic indicators of hydrogen-induced cracking (HIC) where hydrogen diffuses into the steel.
Which magnification level is typically the MAXIMUM recommended for unaided visual testing without an optical aid?
Answer: 1x (unaided eye)
Unaided direct visual testing uses 1x magnification (no optical aid); any magnification above 1x requires an approved optical aid.
What is the significance of a 'witness mark' left on a component during fabrication visual inspection?
Answer: It documents that a specific inspection checkpoint was completed
Witness marks (stamps or paint marks) confirm that an authorized inspector examined and accepted the component at a defined checkpoint.
For weld visual inspection, 'overlap' (also called cold lap) is best described as:
Answer: Weld metal that protrudes beyond the joint without fusing to the base metal
Overlap is an imperfection where weld metal flows beyond the toe of the weld and lies on the base metal surface without metallurgical fusion.
When documenting a VT finding, which piece of information is LEAST critical to include in the inspection report?
Answer: The inspector's shift supervisor's home address
A supervisor's personal address is irrelevant to inspection documentation; location, dimensions, inspector ID, and date are all required fields.
A weld exhibiting 'lack of penetration' (LOP) would appear visually as:
Answer: An unfused gap visible at the root of the weld on the back side
Lack of penetration appears as an unfilled groove or gap at the weld root, often visible when the back side is accessible for inspection.
The ASME Boiler and Pressure Vessel Code Section V Article 9 governs:
Answer: Visual examination methods and requirements
ASME BPVC Section V, Article 9 specifically covers visual examination requirements including methods, lighting, and personnel qualification.