Abstract: An apparatus and method for depositing an overlay material onto a metal surface. An electroslag strip overlaying process which distributes flux through a trailing flux tube and a forward flux tube eliminates many of the problems associated with electroslag overlaying techniques. The apparatus and method significantly improves the quality of the overlay surface, and permits overlays to be made within the small confines of pipes and pipe fittings having straight or curved surfaces.

Abstract: A method of applying a welded overlay to the interior surface of curved hollow articles such as 90 degree elbows utilizing a submerged arc welding gun curved to follow the radius of the hollow article and comprised of an elongated cylindrical body (27) and a curved weld head (10), welding tip holder (24) and welding tip (28) and incorporating a flux conveying system (16), (18) and (20) and a plurality of air release slots (22) by which the flow of flux to the weld area is controlled. A first series of overlapping welds is applied longitudinally to the interior surface of the hollow article to cover 90 degrees of the surface therein. The article is rotated and a second series of overlapping welds are applied 180 degrees from the first series and again covering 90 degrees of the interior surface. A third series of overlapping welds are applied beginning at either of the end welds of the first series and covering 90 degrees of the interior surface.