DRIP IRRIGATION TUBE AND METHOD OF MANUFACTURING SAME

摘要

The invention relates to a plastic drip irrigation tube and a method of manufacturing such a tube. The tube (15) is formed from an extruded inner part (25) which has impressed into its outer surface a series of long tortuous channels (17) which extend generally longitudinally of the tube (15). An outer part (26) is then extruded over and is coextensive with the inner part (25) to form an essentially integral drip irrigation tube (15). The tortuous channels (17) are arranged to provide a significant pressure reduction between an inlet (16) and an outlet (27). The tortuous channels (17) are impressed into the outer surface of the inner part (25) by a number of segment dies radially arranged around the inner part (25) with an internal mandrel providing support and reaction for the segment dies during the impressing operation.