METHOD OF DEFECT-FREE HYBRID LASER-ARC WELDING OF THICK-WALL BUTT JOINTS Russian patent published in 2019 - IPC B23K26/348 B23K9/00 B23K33/00 B23P6/00 

FIELD: technological processes.

SUBSTANCE: invention relates to hybrid laser-arc welding of metal structures with thickness of 12 mm and higher, in particular, to welding of longitudinal seams of molded pipe billets during production of large-diameter pipes from rolled sheet with wall thickness of up to 50 mm. Method of hybrid laser-arc welding of thick-wall butt joints involves making of root seam by electric arc welding with consumable electrode in protective gas medium together with laser welding. Root top defects are detected at a depth limited by half the height of the root seam, elimination of root seam defects by making an additional weld using a defocused laser beam with a focal spot diameter of 1 to 8 mm. Then external and internal lining seams are applied.

EFFECT: improving operational characteristics of the article with a welded seam, providing quality of the welded joint at reduction of material consumption of the method along the way of eliminating equipment providing defect suppression.

3 cl, 1 ex