... roll 2.Winding formation 3.Blown film smoothness double-colour film blowing machine I plant the production of dualmode first prize ... Feeding a extrusion die at the same time,coiling traction device that can effectively improve colorfilm production.2. Screw,cylinder used ... hard chromium plating,and its structure mandral spiral type,melt extrusion material uniform,thin-film-blowing finish well, air-cooled ...