What does the term "overlap" mean in SMAW?

The term "overlap" in Shielded Metal Arc Welding (SMAW) specifically refers to a defect characterized by the weld metal extending over the base metal surface without achieving proper fusion. This issue arises when the welding technique or parameters are not ideal, leading to a situation where the weld metal does not bond correctly with the base material, creating a visible defect on the surface.

Understanding overlap is crucial as it directly affects the quality and integrity of the weld. If not addressed, overlap can weaken the joint, leading to potential failures in the welded structure. This understanding is essential for welders, as they must maintain the correct angle, travel speed, and heat input to avoid such defects and ensure a strong, reliable weld.

The other choices do not accurately define "overlap" within the context of SMAW. The descriptions of joint types, measurements of heat, or techniques aimed at aesthetic appeal do not encapsulate the specific definition associated with the overlap phenomenon in welding practices.