Cone low drift nozzles - insights
Hollow cone nozzle
Hollowcone nozzles produce a crown ground pattern with inner drops having a diameter which is 2-3 times smaller than the diameter of outer drops. Their spraying angle is usually between 40° and 80°, whereas their spraying diagram shows a deeper depression in its central section.
Hollowcone Ceramic ISO 80°
Ground pattern
Spraying diagram
Correct assembly of the HCA nozzles On the brass nozzle holder
Choice of spraying angle Depending on distance to The vegetation
Hollowcone Ceramic ISO 80°
Hollowcone Ceramic ISO 60°
Hollowcone Ceramic ISO 40°
By using nozzles with different spraying angles, it is possible to optimise the spray overlapping on the vegetation and the exploitation of the air produced by the fan, reducing product waste.
Introduction drift
Drift is usually caused by wind action, which introduces a certain amount of pesticide into the environment causing pollution. Today this is a significant problem due to increased environmental awareness. Therefore many nozzle manufacturers are searching a solution to limit this problem.
Some experiments made by DISAFA in Torino in vineyards and orchards have shown that drift plays a major role. Experiments evidenced a 16% drift percentage when spraying a chemical product just three meters away from the target area. A controlled drift helps reducing air pollution, safeguarding water resources and health and safety of human beings, livestock and birds, and improving spraying quality, resulting in increased crop growth and lowered production costs.
Main factors causing drift
- drop size
- weather conditions
- operating height
- working speed
- pesticide specifications
Drop size
Generally speaking, the longer drops fly in the air the higher the possibility they are driven off the target by the wind. Small droplets offer a good coverage but are prone to drift as they are very light. As a matter of fact, they fly much longer and can be driven for long distances by the wind. Theoretically a drop released from three meters under breezy conditions (wind 1.3 m/s, 20 °C and RH 80%) is driven for 3 m if it has a diameter of 200 μm and 130 km if it has a diameter of 1 μm!
Drops under 50 μm are therefore not recommended as they fly for a longer time, even until evaporated, losing any control. Generally speaking, drops should never be under 200 μm. The use of drops with an average diameter of 200-300 μm is recommended.
Drift value according to drop size
Flight time of a drop according to its diameter
