Per B31.3 how much of the fabrication should be visually examined for a pipe in severe cyclic service?

Per B31.3 how much of the fabrication should be visually examined for a pipe in severe cyclic service?

• A. 50%
• B. 75%
• C. 25%
• D. 100%

Answer: (D)

In severe cyclic service, every part of the fabrication must be checked by eye because fatigue cracks can start at any surface flaw and then grow with repeated loading. Visual inspection of the entire fabrication ensures there are no hidden defects—like cracks, undercut, misalignment, or surface damage—that could become critical under frequent start‑stop or pressure/temperature cycling. If only a portion were examined, a flaw could be missed and potentially propagate under service. So the requirement is 100% visual examination to reliably detect any surface defects anywhere in the fabrication.

In severe cyclic service, every part of the fabrication must be checked by eye because fatigue cracks can start at any surface flaw and then grow with repeated loading. Visual inspection of the entire fabrication ensures there are no hidden defects—like cracks, undercut, misalignment, or surface damage—that could become critical under frequent start‑stop or pressure/temperature cycling. If only a portion were examined, a flaw could be missed and potentially propagate under service. So the requirement is 100% visual examination to reliably detect any surface defects anywhere in the fabrication.