12
Installation and assembly
recommendations for
axial fans
12.1 Air inlet
A uniform, swirl-free air inlet velocity distribution must
be guaranteed.
Installation in ducts and pipes
An inflow and outflow dis-
tance of 2.5 x D (fan diam-
eter) must be provided.
Ideal inflow and outflow
distance
Inflow from a smaller duct:
Incorrect
Correct
Inflow from a smaller duct
results in power losses
and increases the noise
level.
If the installation of ideal
inflow distance is not pos-
sible, a transition piece
and a pipe with a length of
2.5 x D (fan diameter)
must be used.
Straight inflow from a larger duct:
Incorrect
Correct
Inflow from a larger duct
results in power losses
and increases the noise
level.
Fit an optimised suction
nozzle in conjunction with
a flexible connector. Size
flexible connectors so that
they are two nominal sizes
bigger than the fan’s nom-
inal size.
If the installation of ideal
inflow distance is not pos-
sible, a transition piece
and a pipe with a length of
2.5 x D (fan diameter)
must be used.
Lateral inflow from a larger duct:
Incorrect
Correct
Lateral inflow from a
larger duct leads to power
losses and increases the
noise level.
Install baffle plates:
cWidth (2) = 0.6 x
spacing (1)
Number: min. 5
Use reverse dampers in
the intake duct.
Install a flexible connector
to further improve the
inflow. Size flexible con-
nectors so that they are
two nominal sizes bigger
than the fan’s nominal
size.
Installation and assembly recommendations f...
Air inlet
Axial fans AXO/BVAXO; AXN/BVAXN; ZAXN/BVZAXN
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