METHOD OF MAKING BUTT WELDS ON PIPES Russian patent published in 2007 - IPC B23K28/02 B23K31/02 B23K37/08 

FIELD: mechanical engineering; welding.

SUBSTANCE: invention relates to plastic metal working and it can be used in making of pipe studs. Methods includes preparatory operations on pipes, assembling of pipes with subsequent argon-arc welding of pipe end by non-consumable electrode with use of filler material. Preliminarily, ends of pipes to be welded are calibrated by expanding in cylinder, and pipes are assembled on mandrel with use of intermediate member in form of ring made of cladding material which is placed between end faces of pipes to provide contact, welds are formed by welding pipe material with cladding material of ring at both sides. The pipe butt joint is heated and is subjected to hot upsetting on mandrel with cladding of surfaces of pipe butt joint at plastic flow of cladding material of ring relative to weld and near-weld zones according to scheme of tri-axial nonuniform compression and outer diameter of pipe butt weld is made equal to initial outer diameter.

EFFECT: improved quality of pipe studs owing to cladding of inner and outer surfaces of welds and elimination of defects in welds.

7 dwg