METHOD OF CONTACT BUTT-SEAM WELDING BY FLOWING OF METAL STRIPS Russian patent published in 2009 - IPC B23K11/04 

FIELD: process engineering.

SUBSTANCE: invention relates to welding, namely to method of contact butt-seam welding by flowing of metal strips and can be used in pipe welding. Proposed method comprises heating pipe bearing faces till flowing of strips by secondary welding voltage and forming welded joint by deforming bearing faces in upsetting. Strip bearing faces are heated at secondary welding voltage proportional to cross section of welded strips and average rate of flowing equal to 1.2…2.5 mm/s. By the end of flowing its rate is increased to maximum values of 10…12 mm/s at bearing face current density equal to 15…20 A/mm². Welding joint is produced in upsetting making 0.5…0.7 δ at upsetting pressure of 40…80 MPa and duration under current not exceeding 0.1 s. Joint upset metal extends beyond strips for not over 0.1…0.2 δ, while upsetting strip width does not exceed 0.3 δ, where δ is strip thickness in mm.

EFFECT: sound welded joint of bands.

3 dwg, 1 ex