Centre Pivot or Lateral Move systems consist of the following components:
- A span is the pipe and framework between two towers
- A tower supports the spans and contains drive mechanisms and wheels.
- Outlets are the points at which water exits the main pipes
- Emitters are attached at outlets either directly or on rigid or flexible droppers. Water isapplied to the plants throughemitters
- Droppers are rigid or flexible small diameter pipes that allow emitters to be placed closer to the ground
Lateral Move systems share similar technology to pivots and are suited to large rectangular areas – up to 200 ha.
This from: http://irrigazette.com/en/news/invest-centre-pivot-or-lateral-move-systems