METHOD OF CONTACT BUTT WELDING OF PIPES WITH ACTIVATING FLUX Russian patent published in 2015 - IPC B23K11/04 B23K101/06 

FIELD: metallurgy.

SUBSTANCE: activating flux is applied to surface of the welded pipes. Layer of salt or salt mixture is applied to the external surface, they are selected from group of fluoride salts of alkali and alkali-earth metals. Layer of salt or salt mixture is applied to the internal surface, they are selected from group of chloride salts of alkali and alkali-earth metals. Alkali metals are selected from the group: lithium, potassium, sodium, and alkali-earth metals are selected from the group: calcium, barium, magnesium.

EFFECT: method of contact butt welding improves quality of the welded joints, and mechanical characteristics of the pipe welded joints.

3 cl, 1 dwg, 2 tbl