|
Hand move sprinkler systems are a series of light weight pipeline
(aluminium, plastic or layflat) sections that are moved manually from
one zone to the other (see
pictures). Hand move sprinkler irrigation systems are normally
the lowest cost sprinkler systems which offer growers flexibility and are
the easiest systems to maintain. They are very labour intensive,
therefore, are usually found in areas where man power is abundant or the
labour cost
is
low.
In a typical hand move sprinkler irrigation
system a mainline is installed from the pump to the field where a submain
breaks the field into small blocks. The submain has a series of hydrants
with take-off valves to provide water to the lateral. The mainlines can be
either aluminium above ground or buried PVC. The submain and laterals are
aluminium pipes with couplers and fittings made of aluminium or galvanised
steel. The couples and fittings
(because of the gaskets) allow the pipes to be
easily drained, un-coupled, moved and re-coupled.
After a section of the field has been
irrigated, the hydrants are closed and the laterals are drained and
carried to the next position.
Impact sprinklers (more than one on a rigid
aluminium or PVC pipe) or big volume/heavy duty - also called large area sprinklers/guns
- are equally spaced along the
lateral lines.
The sprinklers are mounted on risers.
Alternation in riser
heights, spacing of sprinklers/laterals and water application
rates make these
systems suitable for almost any crop, except to tall growing field crops -
due to difficulty in repositioning laterals. The flexibility of the hand move sprinklers
will adapt to oddly shaped fields, to any variety of crops and to any soil
conditions.
Power
requirement is based on the sprinkler type (low, medium
or high
pressure). Careful
design is needed to match the sprinkler spacing, application rate and the
infiltration rate of the soil. Efficiency can range between 65-75 %.
Turn-key price for a hand move sprinkler
system would be around 2,100-3,900 AUD/ha. |