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Sizing
Your Compressed Air System
Any
compressed air
system must be
controlled, regulated,
and sized to
ensure that an
adequate volume
of air, at a
pressure and
purity necessary
to satisfy user
requirements,
is delivered
to the most remote
outlet during
the period of
heaviest anticipated
use. Some safety
factor must be
also incorporated
into the system
to accommodate
additional pressure
drop for some
period of extremely
high use if appropriate
for the facility.
-
Locate
and identify each
process, workstation, or piece of equipment
using compressed air.
-
Determine
volume
of air used
at
each location.
-
Determine
pressure range
required at
each location.
-
Determine
conditioning
requirements for each
item.
-
Establish how
much time
the individual
tool or
process will
be in
actual use
for a
specific period
of time
(duty cycle).
-
Establish the
maximum number
of locations
that may
be used
simultaneously on
each branch,
main, and
for the
project as
a whole
(use factor).
-
Establish the
extent of
allowable leakage.
-
Establish
any
allowance
for
future expansion.
-
Make
a
preliminary
piping
layout
and
assign
preliminary
pressure
drop.
-
Select
the
air
compressor
type,
conditioning
equipment,
and
air
inlet
locations
making
sure
that
consistent
SCFM
or
ACFM
is
used
for
both
the
system
and
compressor
capacity
rating.
-
Produce
a
final
piping
layout
and
size
the
piping
network
Piping layout on the plans
shall be reasonably complete, with checking
for space, clearances, interference, and equipment
drops. In order to use pressure drop tables,
it is necessary to find the equivalent length
of run from the compressor to the farthest
point in the piping system. The reason for
this is that the various pipe-sizing tables
are developed for a pressure drop using friction
loss for a given length of pipe.
-
Measuring
the actual length is the first step. In addition,
the affects of the fittings
must be considered.
-
Determine
the actual pressure drop that will occur
only in the piping
system. Generally accepted practice
is
to allow
10% of the
proposed system pressure
for pipe friction loss. It
is a good practice to oversize
distribution mains to allow for
future growth as well
as the addition of conditioning
equipment.
-
Size
the piping using the appropriate charts,
having calculated
the SCFM and the allowable
friction loss in each
section of the piping being sized.
-
The
temperature used to calculate the friction
loss is 60ºF (16ºC).
Sizing Tool: Depending
on the flow and pressure drop required, choose
your diameter.
(values for a pressure of 8 bar -116 PSI - and
5% pressure drop).
* Pressure drop over 5%
Flow Calculator: Please
contact us for your free download. |
