Use and Care Manual

-18-
Model T28798 (Mfd. Since 01/20)
Figure 12. Example of flexible metal duct.
Flexible Duct
Flexible hose is generally used for short runs and
at rigid duct-to-machine connections. The supe-
rior choice here is metal flex hose that is designed
to be flexible, yet be as smooth as possible inside
to reduce static pressure loss. DO NOT use dryer
vent hose because it tends to collapse.
Ensure Required CFM at Machine
Since each machine produces a different amount
of dust, the requirements for the minimum amount
of CFM to move that dust is unique to the machine.
Knowing this required CFM is important to gaug-
ing what size duct to use.
For best results when using the Y-inlet, we recom-
mend installing blast gates to control airflow for
each line near the Y-inlet.
Figure 13. Approximate required airflow for
machines based on dust port size.
Machine
Dust Port Size
Approximate
Required CFM
2" 100
2.5" 150
3" 250
4" 400
5" 600
6" 850
7" 1200
8" 1600
9" 2000
10" 2500
Refer to Figure 13 for a close estimation of the
airflow each dust-producing machine requires.
Machines that generate the most dust should be
placed as close as possible to the dust collector.
Always guard against
static electrical build up
by grounding all dust
collection lines.
System Grounding
To guard against static electrical buildup, we
strongly recommend replacing any plastic dust
ports on dust-producing machines with metal
equivalents.
If you absolutely must use any plastic duct or
components, they must be completely grounded
and bonded to the metal frame of a grounded
machine by wrapping the flex hose with an exter-
nal ground wire connected to both machines as
shown in Figure 14. Ensure that each machine is
continuously grounded to the grounding terminal
in your electric service panel.
Figure 14. Example showing how to ground and
bond ducting with a grounding wire.
External
Ground Wire
Flex-Hose
Ground
Screw
Plastic
Dust Port
Grounding wire bypasses
plastic components to bond
ducting to grounded machine