Abstract: A system for manufacturing an irrigation pipe comprises an extrusion unit, a calibrator unit, a cooling unit for cooling the irrigation pipe in a cooling liquid, and a traction unit for drawing the irrigation pipe in the cooling unit. The cooling unit comprises a device for detecting holes in the wall of the irrigation pipe and arranged for being immersed in the cooling liquid. The device for detecting holes comprises at least one optical transmitter and at least one optical receiver which define an optical barrier. The device is arranged so that the holes in the irrigation pipe located below the device produce gas bubbles which modify the optical barrier.

Abstract: A system for manufacturing an irrigation pipe (100) comprising an extrusion unit (300) a calibrator unit (400) a cooling unit (600) for cooling the irrigation pipe (100) in a cooling liquid (30) a traction unit (500) for drawing the irrigation pipe (100) in the cooling unit (600) the cooling unit comprising a device for detecting holes (102) in the wall of the irrigation pipe (100) and arranged for being immersed in the cooling liquid (30), this device for detecting holes comprising at least one optical transmitter (1) and at least one optical receiver (2) which define an optical barrier (10), this device being arranged so that the holes (102) in the irrigation pipe (100) located below this device produce gas bubbles (20) which modify this optical barrier (10).