LINE FOR MANUFACTURING HELICAL-SEAM TUBES FROM SEPARATE SHEETS Russian patent published in 2007 - IPC B21C37/12 

FIELD: tube production, possibly manufacture of helical-seam large-diameter tubes for main and enterprise gas and oil conduits.

SUBSTANCE: line includes stationary and mobile plants for butt welding of two sheets by cross seams to one section and welding said section to continuous strip; shaping-welding mill; plant for welding outer cross seams in tube. In front of stationary and mobile butt-welding plants there are apparatuses for heating before welding end portions of sheets, sections and continuous strip along length 150-200 mm. First of such apparatuses is mounted stationary and second apparatus may move together with butt-welding plant. In front of plant for welding outer cross seam there is apparatus for heating tube portion including inner cross seam plus 100-300 mm at each side of it.

EFFECT: improved operational reliability of helical-seam tubes due to their enhanced ductile properties, improved shape of cross seams of helical-seam tubes, lowered trend to cracking.

1 dwg