APPARATUS AND METHOD OF MANUFACTURING PRESSURE COMPENSATOR TYPE DRIP IRRIGATION TUBES WITH DESIRED MOLECULAR ORIENTATION AND TUBES OBTAINED THEREBY

摘要

A method for manufacturing high speed pressure compensator-type drip irrigation tubes and the tubes obtained thereby having absolute radial orientation of molecular chains, the orientation imparting strength as well as flexibility to the tube material. The said method comprises extruding a tube using a plurality of extruders; blowing up the extruded tube by introducing a pressure inside the tube relatively higher than the pressure outside the tube; drawing the blown tube simultaneously to the blowing of tube; flattening the blown tube by heat welding the collapsed halves together and forming a tape immediately, subsequent to the process of blowing and drawing the tube; extrusion of a bonding polymer on one border of the tape; printing flow channels into the hot and viscous bonding polymer; and forming a tube by lengthwise folding the tape and heat welding the overlapping borders together using the bonding polymer.