Calibration
16
Nozzle Selection
Refer to the che
mical manufacturer’s information
to determine the recommended application rate
in litres per hectare (l/ha) for your particular
situation. Then determine the speed in kilometres
per hour (kmh) at which you intend to spray,
taking into consideration the ground conditions of
the area to be sprayed.
Using the appropriate chart for your boom, select
the most suitable nozzle to use at the normal
recommended pressure of 3.0 Bar. The leading
digits in the nozzle number indicate whether it is
an 80
0
or 110
0
fan angle and the last two digits
refer to the size of the opening. Nozzles are ISO
colour coded for easy identification.
All Silvan booms are fitted with air induction
nozzles suitable for a pressure range from 1.5 to
6.0 Bar. The chart below applies to ISO colour
code nozzles.
For sprayers fitted with a Vineyard boom refer to
the calibrating chart supplied with the boom. If
necessary obtain this information from your
Silvan dealer.
An example of how to use the calibration chart is
shown below.
Using the Calibration Charts
For example, a rate of 96 l/ha can be achieved at a ground speed of 10 kmh using 3.0 Bar pressure with a
110-02 yellow nozzle - refer to the nozzle selection chart on the previous page.
If the exact application rate does not appear in the chart it can be achieved by slightly adjusting the speed
or pressure. For example, if a rate of 100 l/ha is required rather than 96 l/ha, it can be achieved with the
same yellow nozzles by reducing the speed to 9.5 kmh or increasing pressure to approximately 3.2 Bar.
Alternatively, the same rate of 100 l/ha could also be achieved with a larger nozzle and faster operating
speed. By referring to the nozzle chart on the previous page it can be seen that a 110-03 blue nozzle will
give this rate at a little under 14 kmh and 3.0 Bar (the rate shown on the chart at 14 kmh is 103 l/ha ).
It can thus be seen that a variety of choices exist for most application rates and the final selection of nozzle,
speed and pressure will depend upon the factors which best suit your conditions.
Always perform a calibration check to confirm your nozzle selection, as described on page 14.
