Pneumatic conveying:
The conveying capacity of the TRL blowers are
depending on the set-up of the pipe system. Therefore
carefully read the following instructions regarding the
set-up of the pipe system.
When using the TRL blower for pneumatic conveying,
the material must be fed into the pipe system by a
rotary valve or a venturi.
Rotary valve
Please note that the blowers TRL 20/40 (50Hz) and
TRL 30/50 (60Hz) normally must not be operated
without the use of a venturi. Otherwise, the motor can
be overloaded. The venturi can however be left out if
the air capacity of the blower is limited in a way that
the rated current of the motor is not exceeded. (see
type plate on motor).
The air outlet on the TRL blowers is dimensioned for
Kongskilde's OK 160 pipe system (outside diameter
160mm / 6.3"). The following instructions are therefore
based on this pipe system, but the same principles are
applying for other types of pipe systems as well.
Installation of venturi
The venturi can be fitted in the pipeline wherever it is
required. Only one venturi may be fitted in any one
pipeline. With excessive material pressure above the
venturi or with a long vertical pipeline, the venturi must
be fitted with a shutter at the intake, apart from this the
venturi is self-regulating.
Check that the venturi is pointing in the right direction.
The direction of the air-flow is indicated by an arrow on
the venturi.
Installation of rotary valve
Check that the rotary valve is placed in the right way. A
small air flap is mounted in the air supply side. The air
flap directs the airflow downwards and away from the
rotor, so that the material will easily fall down into the
airstream. If the rotary valve is placed in the opposite
direction, the material will not fall down into the
airstream.
Venturi
Also ensure that the rotor runs in the correct direction.
The rotor shall rotate so that the grain falls into the air
entry side of the rotary valve. If the rotary valve is seen
as illustrated below, the rotor shall run clockwise.
It is recommended to install a wide open hopper above
the rotary valve inlet. The inlet of the rotary valve shall
be considerably larger than the feeding spout. An
overpressure of air in the chambers of the rotary valve
is constantly built-up in the chambers returning from
the pressure side. This air shall slip away, which is not
possible when the feeding spout is clamped directly on
to the rotary valve inlet. The consequence hereof will
often be inferior filling of the chambers and plugging of
the pipes above the rotary valve.
To avoid irregular feeding, which e.g. might be the
case after a dump weigher, a shutter can be mounted
right above the rotary valve. The shutter is adjusted
to obtain an even and constant flow of material to the
rotary valve.
The rotary valve will normally have a higher capacity
than the blower, hence the input capacity of material
must be adjusted with a shutter.
CAD 30
CAD 50
Shutter for adjustting
of grain flow
Right
Several rotary valves on one pipe line
Airflow passing a rotary valve in a pipe line does not
reduce capacity. Passing material through many
rotary valves in the same pipe line reduce capacity
considerably.
Therefore max. 3 rotary valves in line are
recommended. With more than 3 rotary valves, a "by
pass" can be made.
Air flap
Flow direktion
CAD 20
CAD 40
Hopper or large inlet with considerable
larger diameter then the grain outlet
Shutter
Wrong
9