Compressor Cooling And Lubrication System, Function - Sullair 3000P User Manual

3000P-4500 USER MANUAL
2.4 COMPRESSOR COOLING
AND LUBRICATION
SYSTEM, FUNCTIONAL
DESCRIPTION
Refer to Figure 2-3 or Figure 2-4. The Cooling and
Lubrication System (air-cooled version) consists of a
fan, fan motor, radiator-type aftercooler/fluid cooler,
full flow fluid filter, thermal valve, and interconnecting
hoses. For water-cooled models, two shell and tube
heat exchangers are substituted for the radiator-type
cooler listed above. The pressure in the separator/
sump tank causes fluid flow by forcing the fluid from
the high pressure area of the separator/sump tank to
an area of lower pressure in the compressor unit.
Fluid flows from the bottom of the separator/sump
tank to the thermal valve. The thermal valve is fully
open when the fluid temperature is below 185°F
(85°C) [200°F (93°C) for 24KT] and pressures are
rated above 150 psig. The fluid passes through the
thermal valve, the main filter and directly to the
compressor unit where it lubricates, cools and seals
the rotors and the compression chamber.
As the discharge temperature rises above 185°F (85
°C), due to the heat of compression, the thermal
valve begins to adjust and a portion of the fluid then
flows through the cooler. From the cooler the fluid
flows to the fluid filter and then on to the compressor
unit.
A portion of the fluid flowing to the compressor is
routed to the anti-friction bearings which support the
rotors inside the compressor unit.
The fluid filter has a replacement element and an
integral pressure bypass valve. Refer to Lubrication
Change Recommendations and Maintenance, Fluid
on page 27.
Water-cooled models have a water pressure switch
to prevent operation with inadequate water pressure.
2.5 COMPRESSOR DISCHARGE
SYSTEM, FUNCTIONAL
DESCRIPTION
Refer to Figure 2-3 or Figure 2-4. The compressor
unit discharges the compressed air/fluid mixture into
the combination separator/sump tank.
The separator/sump has three basic functions:
1. 1. It acts as a primary fluid separator.
2. 2. Serves as the compressor fluid sump.
3. 3. Houses the final fluid separator.
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The compressed air/fluid
separator/sump tank and flows through an internal
baffle system. The direction of movement is changed
and its velocity significantly reduced, thus causing
large droplets of fluid to form and fall to the bottom of
the separator/sump tank. The fractional percentage
of fluid remaining in the compressed air collects on
the surface of the separator element as the
compressed air flows through the separator. A return
line (or scavenge tube) leads from the dry side of the
separator/sump tank to a medium pressure region of
the compressor unit. Fluid collecting on the bottom of
the separator is returned to the compressor by a
pressure differential between the separator/sump
and the compressor. A visual sight glass is located
on the return line to observe this fluid flow. There is
also an orifice in this return line (protected by a
strainer) to assure proper flow. The separator system
reduces the fluid carry-over at nominal rated
pressures to less than 1 ppm (parts per million). A
message on the WS Controller indicates if abnormal
pressure drop through the separator develops. Refer
to Lubrication Change Recommendations
Maintenance, Fluid on page 27.
A minimum pressure/check
downstream from the separator, assures a minimum
separator/sump pressure of 50 psig (3.4 bar) during
loaded conditions. This pressure is necessary for
proper air/fluid separation
circulation.
A terminal check valve is incorporated into the
minimum pressure/check
compressed air in the service line from bleeding back
into the separator/sump on shutdown and during
operation of the compressor in an unloaded
condition.
A pressure relief valve (located on the wet side of the
separator) is set to open if the separator/sump tank
pressure exceeds the separator/sump tank rating.
The WS Controller will shut down the compressor if
the discharge temperature reaches 235°F (113°C).
WARNING
DO NOT remove caps, plugs, and/or other
components when compressor is running
or pressurized. Stop compressor and
relieve all internal pressure before doing so.
Fluid is added to the separator/sump tank via a
capped fluid filler opening, placed low on the tank to
prevent overfilling of the separator/sump tank. A
sight glass enables the operator to visually monitor
the separator/sump tank fluid level.
SECTION 2
mixture enters the
and
valve, located
and proper fluid
valve to prevent