13
4.4.
Suction
line
Dimensioning
The
suction
line
should
be
dimensioned
so
that
a
flow
speed
of
around
65
ft/s
is
ensured
in
all
horizontal
pipe
sections.
The
maximum
pipe
diameter
may
not
be
larger
than
the
air
inlet
port
of
the
device.
Material
We
recommend
that
you
use
ductwork made
from
galvanized
sheet
metal
in
order
to
prevent
the
formation
of
rust
film.
In
the
case
of
longitudinally
slip
‐
jointed
pipes,
the
longitudinal
seam
should
point
upwards
during
as
‐
sembly.
Fittings
Pipe
bends
must
have
an
internal
radius
that
is
at
least
equal
to
the
pipe
diameter.
Pipe
outlets
should
be
at
an
angle
of
30°.
Device
connection
The
connection
of
the
device
must
be
flexible.
A
rigid
connection
is
not
al
‐
lowed.
Cleaning
openings
In
horizontal
pipe
sections,
a
cleaning
opening
should
be
installed
every
10
to
16
feet.
Additional
cleaning
openings
are
recommended
before
and
after
pipe
branches.
If
a
sound
absorber
is
installed
in
the
ductwork,
cleaning
openings
are
re
‐
quired
before
and
after
it.
Shut
‐
off
valves
We
recommend
that
you
install
vertical,
manually
operated
shut
‐
off
valves
directly
on
the
individual
collection
points
in
order
to
adjust
the
air
sub
‐
flows.
Attachment
of
pipes
The
ductwork must
be
secured
using
suitable
means
of
attachment
in
ac
‐
cordance
with
the
load.
The
ductwork
must
not
be
propped
up
by
the
de
‐
vice!
Potential
equalization
For
the
extraction
of
non
‐
conductive
dusts,
all
dust
collection
elements
and
each
individual
pipe
section
(including
flexible
tubing)
must
be
grounded
by
means
of
potential
equalization.
Seals
must
be
electrically
conductive.
Otherwise,
potential
equalization
sys
‐
tems
must
be
used
throughout
the
ductwork
system.
The
connection
of
multiple
potential
equalization
systems
to
a
single
at
‐
tachment
point
is
not
allowed.
Each
connection
must
be
individually
at
‐
tached
to
a
copper
bar.
This
bar
itself
must
be
grounded
with
the
switching
system.
