METHOD FOR CONTACT FLASH WELDING Russian patent published in 2018 - IPC B23K11/04 B23K101/06 

FIELD: valves industry.

SUBSTANCE: invention can be used in butt-contact welding, in particular, trunk, field and offshore pipelines. Ends of pipes to be welded are centered in welding equipment with allowance for melting and immersion. Immersion pipe ends heated by welding current is performed by applying a pulsating load to a value of the relative true deformation of the ends of the welded pipes depending on the maximum thickness of the deformed part of the joint of welded pipes and the initial thickness of their walls. Specific unit pulse of the maximum welding force is determined as a function of the specific welding force and the time of action of said unit pulse, taking into account the empirical coefficient. Specific welding force is selected depending on the yield strength of the welded parts at the immersion temperature and pulsation frequency of the load for immersion in the range of 1.0–25 Hz, and the time is set in the interval 0.01–1 s. Load pulsation frequency is varied during immersion in proportion to its magnitude.

EFFECT: method improves the quality of the welded joint.

1 cl, 5 dwg