Dimensions and shape of the weld have a significant influence on the quality of the welded joint. The influence of defects present in the welded joint on the strength of the welded structure depends largely on the conditions of operation, distribution, and magnitude of residual, as well as working stresses arising during operation, and the totality of these stresses. Influence of defect size becomes insignificant, if lacks-of-penetration are located in the zone of high tensile residual stresses. In addition to defects, the welded joint’s performance is greatly influenced by the shape and dimensions of the penetration zone, bead and weld root, and the smooth transition from the base metal to the deposited metal. The time of the arc discharge action on the copper alloy has a much greater influence on the process of the melt flowing into the gap between the plates.