AUTOMATIC ARGON-ARC PULSE WELDING METHOD FOR MAKING STEEL TUBES WITH USE OF NON-MELTING ELECTRODE Russian patent published in 2005 - IPC

FIELD: electric arc welding of materials by means of non-melting electrode, namely methods for automatic argon-arc pulse welding of steel tubes.

SUBSTANCE: method comprises steps of preliminarily dressing tube butts and forming annular chamfers on inner surfaces of butts; abutting tubes; moving welded edges relative to electrode by step axial rotation of abutted tubes at revolution number 1 -1.5 rev/min; igniting arc 2 - 5 s before starting rotation of tube in order to heat welded seam zone; performing welding by means of torch inclined to tube axis by angle 60 - 85° relative to vertical line; sustaining electric current intensity in range 110 - 155 A for pulse duration 0.7 - 0.9 s; keeping electric current at pause period in range 10 - 30 A for pulse duration 0.5 - 0.7 s. Overlapping value of welded seam is in range 10 - 25 mm. It allows eliminate cracking of welded seam of tubes at bending samples by angle exceeding 160°.

EFFECT: enhanced quality of welded seam of tubes.

3 dwg, 1 tbl