When accomplishing welding repairs using the electric arc welding process, what statement is true concerning the characteristics of a good quality weld when welding a single-V butt joint?

Correct Answer: Option D — There should be a slight reinforcement or build-up of material on the top surface, and there should be root penetration along the bottom surface.

A sound single-V butt weld requires slight reinforcement on the top surface to ensure the weld throat is sufficient to carry the design load. Simultaneously, full root penetration is mandatory to ensure the joint is fused through the entire thickness of the plate, preventing internal voids or weak spots.