Doosan 12/154, Operation & Maintenance Manual

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12/154
IQ SYSTEM OPERATING INSTRUCTIONS - 2
The compressed air exits the separator tank through the top cover
piping, and can then travel along one of two paths, selectable via
manual valving.
One path allows Standard Operation, which bypasses the IQ
System, and delivers air quality equivalent to a standard oil-flooded
portable compressor. If the IQ System is enabled by proper setting of
the selector valve, the compressed air first enters the aftercooler.
The aftercooler is cooled by the incoming compressor package air.
The compressed air and condensate (water with a small amount of
compressor lubricant) exits the aftercooler and enters the moisture
separator, where most of the condensate is removed. The aerosol oil
is removed down to approximately 0.01 ppm and all particulates are
removed down to 0.01 micron.
At the bottom of the moisture separator and both filters are strainers
and constant-bleed orifices, which are sized to allow the maximum flow
of condensate while minimising compressed air loss.
The condensate lines are then piped together, and the condensate
is injected at a single point into the engine exhaust piping. The
compressed air then travels through the minimum pressure valve, and
out through the service air valve. The air pressure gauge on the
instrument panel indicates the pressure inside the separator tank. A
service air pressure gauge is located inside the front door of the
compressor on the filter support.
If the IQ System is bypassed (Standard Operation selected), the
delivered air pressure will be approximately equal to the separator tank
pressure. If the IQ System operation is selected, the delivered air
pressure will be slightly less, depending on the restriction of the filters.
MAINTENANCE
Daily Maintenance:
Verify, during fullload (maximum compressed air delivery)
operation, the IQ System filter restriction is not excessive. Filter
restriction can be checked at the control panel. The compressor will
shutdown if restriction exceeds recommended values.
Weekly Maintenance:
• Remove Y-strainer screens at the bottom of the moisture separator
and both filters and clean out any residue.
• Verify that the orifices below the Y-strainers are not clogged.
• Verify that the piping from the orifice purge points to the exhaust
system is not clogged.
Yearly Maintenance:
The normal maintenance interval on the primary and secondary IQ
System filters is one year, or earlier if pressure drop becomes
excessive. The compressor will shut down if restriction exceeds
recommended values.
FILTER REPLACEMENT
• With engine stopped, ensure pressure is relieved from air system.
• Remove all wires and hoses connected to drains on bottom of each
filter housing. Inspect fittings and hoses for any blockage. Clean if
necessary.
• Using a chain wrench or similar tool, loosen the housing. The
housing should be removed by hand after loosening, taking care to
prevent the housing from falling to the floor panel.
• Lower the housing to floor panel and lean it against the airend.
Remove and replace the filter element, being careful not to damage
outer wrap.
Verify the part number of new element vs. old element, as the two
IQ filters are of different media.