Micron Herbi4 Instruction Manual page 9

The table below indicates the relationship between total spray volume, flow rate and
walking speed for the HERBI 4 as per the following formula:
Flow rate (ml/min) = 6 x total spray volume (l/ha) x walking speed (m/s) x band width (m)
Total spray volume
(l/ha)
10 (i.e. glyphosate)
20 (i.e. other herbicides)
Note: The flow rates in this table were measured with the spray head 65cm below the level of the liquid in
the tank, using water only. The flow rate will vary with differences in this height and the viscosity of the
spray mix (for very viscous spray mixes it may be necessary to use a larger feed nozzle).
CALIBRATION
Choose and fit the feed nozzle that is likely to be required. The actual flow rate
should be checked holding the HERBI 4 in the spraying position. Remove the feed
nozzle from the spray head by twisting and pulling out, then, once liquid has reached
the feed nozzle, allow the liquid to flow into a suitable container for one minute and
measure the volume dispensed. If the flow rate is not in the recommended flow rate
range of 60 to 150 ml/min change the feed nozzle and repeat the above procedure.
N.B. It is preferable to walk more slowly to achieve the required spray volume than
to use higher flow rates.
Example: Required spray volume rate = 20 l/ha; Flow rate measured = 100 ml/min
Walking speed (m/s) =
i.e. 0.7 m/s or 42 metres in one minute (0.7m x 60s)
Mark out a distance of 42 metres and practice walking it in one minute.
Band width Feed nozzle Flow rate
(m)
1.2
1.2
Flow rate (ml/min)
6 x 1.2 x total spray volume (l/ha)
9
(ml/min)
Blue 72
Blue 72
Yellow 144
Yellow Orange Red
Blue
Increased flow rate
=
7.2 x 20
Walking speed
(m/s)
1
0.5
1
100
= 0.7