LINE FOR MAKING ELECTRICALLY WELDED METALLIC TUBES Russian patent published in 1999 - IPC

FIELD: metallurgical production, namely of electrically welded tubes for large-length water conduits with high demands made to their surface quality, particularly roughness, structure and properties of surface minelayer. SUBSTANCE: line includes coiled band, spraying system, drying chamber, reducing stand with cylindrical rolls, shaping mill, welding apparatus, cutter for removing outer flash, apparatus for applying outer coating. Between spraying chamber and coiled band there is vacuum chamber having sealed inlet, sealed outlet and cooler. First gas jet is arranged in welding zone, electric arc burner - in zone of inner flash, second and third gas jets - in zone for removing outer flash and melting inner flash. Apparatus for applying inner coating onto melted inner flash, on area adjoining to it and on ready tube is arranged after third gas jet. EFFECT: enhanced quality of electrically welded metallic tubes due to high quality of cleaning surface of initial band, ameliorated quality of welded seam due to equalizing profile of inner flash and providing possibility of applying high quality protective coating on inner and outer surfaces of welded seam. 1 dwg