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Rule of thumb: Normal length of stride is 0.7 to 0.9 m, but
can be up to 1.0 m. Measuring the distance is better than
counting the number of steps. Dividing the distance in
meters by the time in minutes produces the walking speed
in meters or yards per minute (m/min)
The
discharge rate per unit time
liters/min is infinitely
variable on the mistblower's metering unit. The required
discharge rate is determined by the area to be treated, the
quantity of solution, the working width and the walking
speed. It can be calculated with the aid of the following
equation:
V
sol
(I) • V
W
(m/min) • b (m)
A (m
2
)
=V
dis
(I/min)
Where:
V
sol
= Quantity of solution
V
W
= Walking speed
b
= Working width
A
= Area
V
dis
= Discharge rate
Preparations for mistblowing
Before starting work it is necessary to determine the follow-
ing points, which affect the liquid discharge rate per unit
area and thus the distribution of active ingredient in the
crop:
•
Working width
•
Walking speed
•
Unit's discharge rate per unit time
•
Position of spray tube (angle from horizontal)
Among other factors, the
working width
is dependent on
the crop and is determined by the distance between rows
of trees, shrubs and bushes. In the case of low-growing
crops, the best working width is about 4 m, but can be up
to 5 m if the user adjusts his walking speed accordingly.
The working width should be marked with stakes to avoid
any deviation.
The
walking speed
can vary greatly from user to user. For
this reason it is advisable to do a trial run with the machine
fueled and the container filled with water, and make a note
of the time taken (stop watch). While walking, the spray
tube should be operated as it will be during the real run
described below.
This trial run is also used to check the working width, i.e.
the greater the width, the slower the walking speed. Check
the distance walked in one minute.