New fertiliser nozzles from manufacturer Teejet Technologies respond to changes in pressure to deliver consistent or variable application rates, eliminating the need for frequent nozzle change-overs or multi-nozzle systems.
The Streamjet VR nozzles have a metering orifice made from synthetic rubber formulated for predictable and consistent elasticity; it gets bigger or smaller with changes in fluid pressure.
This feature enables each nozzle to provide an extended range of application rates – typically equivalent to five fixed-orifice sizes – which TeeJet says makes them an attractive proposition for variable rate applications from prescription maps.
Equally, they allow a wide range of operating speeds to be accommodated when applying liquid fertiliser at a flat rate across fields.
Photo credit: Teejet
There are two designs available – the three-outlet SJ3-VR producing vertical streams and the seven-outlet SJ7-VR that produces an "umbrella" pattern.
Both are produced as a combined tip and body moulding with no moving parts – such as springs, pins and check valves – other than the elastic orifice; both come in two sizes; and both should only be used with flow meter-based control systems.
The Streamjet SJ3-VR produces one vertical and two slightly angled solid streams intended to minimise leaf scorch and be resistant to drift, and is designed to operate at pressures of 1.5 to 7.0 bar (20-100psi).
At 50cm (20in) spacing and 12kph, the SJ3-VR-X1.0 delivers 84 to 344 litres/ha (9-36 gallons/acre), while the SJ3-VR-X2.0 provides 219 to 629 litres/ha (23-166 gallons/acre). TeeJet’s Streamjet SJ7-VR has seven outlets arranged around the bottom edge of the nozzle to project the liquid streams sideways before gravity takes over.
Recommended operating pressure is 2.0 to 5.5 bar (30-80psi), with the red coloured SJ7-VR-X1.0 handling rates of 101 to 294 litres/ha (10-119 gallons/acre) at 12kph.
The blue SJ7-VR-X2.0 delivering 262 to 592 litres/ha (28-63 gallons/acre) at the same speed and nozzle spacing is the latest addition to the range, which is due to be further extended by a smaller "yellow" version later this year.
Name: Streamjet VR
Type: Fertiliser nozzles
Key feature: Elastic metering orifice allows wide range of application rates or operating speeds