Method for making a porous tube, porous tube thereby obtained, and use thereof in irrigation

摘要

A method for making a porous tube for use in irrigation, wherein (a) a uniform mixture (21) of vulcanised rubber particles and a thermoplastic binder is prepared; (b) the mixture (21) is fed through an extruder (30) and heated therein; (c) the mixture (21) is drawn out of the extruder (30) through a die (44) at a linear extrusion speed V1 to form a tube (23); (d) the tube (23) from the die (44) is immersed in a cooling bath (35) in which a percentage linear contraction Ct is caused in the tube (23); (e) the tube (23) from the cooling bath (35) is fed between two feed rollers (27, 28) at a linear withdrawal speed V2; and (f) the tube from the feed rollers (27, 28) is wound onto a spool (25); V1, V2 and Ct being determined by the equation (100-Ct) < 100 V2/V1 < 120.