horsch Tiger AS Series Operating Instructions Manual page 67

Assembly groups
Joker RT machines can be equipped with a
DuoDrill unit for the placement of fine seeds like
rape, grass or mustard.
DuoDrill facility
This facility consists of a seed hopper (capacity
300 l), a pneumatic system with an hydraulic fan,
Venturi type injector and a distributor tower. This
optional equipment is controlled by the electronic
drill control (see correcponding instructions
E-Manager).
Seed hopper
Due to the depositing of dust the seed hopper
should always remain closed. Dust causes
malfunctions and unnecessary wear inside the
metering unit and can thus lead to a reduction
of the seed quantity.
Venturi area
In the Venturi area the seed is injected into the
air flow from the fan. During calibration seed is
taken from the bottom covering.
This covering must be closed and leak
tight to ensure correct functioning.
Pneumatic system
Air losses will have a negative effect on the
distribution.
The hoses and components of the pneu-
matic system must be leak tight and
firmly attached. The distributor must be
regularly checked and cleaned from dirt
and deposits.
Valves for tramline control can be installed, if
demanded.
Fan
The hydraulic fan is directly driven by the tractor
hydraulics.
The generated air flow conveys the seed from
the Venturi pipe to the seed pipes. The required
air quantity depends on seed (type and weight),
seed quantity, working width and sowing speed.
A correct fan speed cannot be specified and must
therefore be determined by tests in the field.
The air flow must not be too weak, so that the
seed does not remain in the hoses and causes
blockage. Too weak an air flow may also have
a negative effect on the distribution.
The fan speed must be adjusted to the field
conditions.
Depending on working width and seed a fan
speed of min. 2000 to 3000 rpm is recom-
mended in order to achieve uniform transverse
distribution.
Fan setting, seed transportation and
seed placement must be checked when
starting sowing, and also at regular inter-
vals when working on large areas.
Air losses caused by deposits on the protection
grille cause blockage in the seed hoses.
Deposits on the fan impeller cause unbalance.
The bearing will thereby be overloaded and can
be damaged.
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