A common approach to preventing these
failures is the fitting of a single filter set at
the outlet of the air compressor or supply
source of the instrument gas. However,
this does nothing to protect downstream
equipment from contaminants introduced
after the air or gas leaves the source. For
example, pipe work is often stored outside,
open to contamination before being
installed. Long pipelines from supply to
instrumentation experience large variations
in temperature, causing moisture to
condense. Simple filter/regulators remove
only little water and no oil to begin with,
and the aggressiveness and impact of air
system contaminants is magnified under
compression. Finally, a "one size fits all"
filter set at the source is inadequate for
most specialized equipment that requires
finer filtration and oil removal.
There is growing awareness of the need
for additional filtration at the point of use.
However, most operators only install a
single filter/regulator. Although this does
help remove particulates, it provides little
in the way of water removal and no oil
removal.
Placing a multi-stage filtration system
that includes a coalescing filter to
remove oil vapour as close as possible
to the equipment using instrument air
or instrument gas protects sensitive
instruments and keeps critical
equipment operating as intended.
04 A white paper
