METHOD OF CONNECTION OF STEEL PIPES PROVIDED WITH INTERNAL PLASTIC LINING Russian patent published in 2004 - IPC

FIELD: pipe line transport; manufacture of pipes and erection of pipe lines. SUBSTANCE: proposed method includes removal of plastic lining from pipes at distance of 80-150 mm from ends and pinching steel rings are placed inside ends of linings and pipes. Ends of lining are secured to ends of pipes by radial deformation of pinching rings inside which protective bush is placed; protective bush is provided with anticorrosive coat, sealing rings made from resilient-elastic material and fitted at ends of bush and heat-insulating ring on outer surface opposite weld seam; edges of pipes are subjected to forced coupling, after which butt welding is performed. Inner ends of pinching rings are provided with radial internal projection and distance between sealing rings of bush exceeds distance between radial projections of pinching rings over end points. EFFECT: enhanced reliability of connection. 2 cl, 1 dwg