Process of making a drip irrigation conduit

A process for producing a drip irrigation conduit having a transverse peripheral extent and having internally heat welded emitter units, each emitter unit having a welded area which has a transverse, peripheral extent which is not greater than half the transverse peripheral extent of the conduit, comprising the steps of:

• continuously extruding an irrigation conduit from an extrusion cross head at a first outer diameter and a first linear velocity;
• passing the extruded conduit through an intermediate zone following said extrusion cross head and into a succeeding calibrator unit so as to be drawn down to a second outer diameter which is less than the first outer diameter and so as to have a second linear velocity greater than the first linear velocity;
• supporting said emitter units over a support region coaxial with the extruded conduit and extending from a first end of said support region within the extruder cross-head to an opposite end thereof within the calibrator unit;
• successively accelerating said supported emitter units so as to attain an emitter unit linear velocity substantially equal to said second linear velocity;
• displacing each supported emitter unit at said emitter unit linear velocity into contact with said extruded conduit where the conduit has substantially attained said second linear velocity;
• displacing each supported emitter unit at said emitter unit linear velocity in contact with the extruded conduit until the emitter unit is internally heat welded to the conduit at substantially said opposite end;
• cooling the extruded conduit and internally heat welded emitter units;
• successively determining the location of the heat welded emitter units in the conduit;
• and
• aperturing the conduit so as to form respective drip outlets for the emitter units.