Compressor Cooling And Lubrication System, Functional Description; Compressor Discharge System, Functional Description - Sullair LS-10 25HP Operators Manual And Parts Lists

Section 2
DESCRIPTION
vides continuous pulse---free compression to meet
your needs.
With a Sullair compressor, there is no mainte-
nance or inspection of the internal parts of the
compressor unit permitted in accordance with
the terms of the warranty.
Sullair 24KT compressors are filled with a fluid
which rarely needs to be changed. In the event a
change of fluid is required, use only Sullair 24KT
fluid.
Mixing of other lubricants within the compressor
unit will void all warranties!
Sullair recommends that a 24KT sample be taken
at the first filter change and sent to the factory for
analysis. This is a free service. The sample kit with
instructions and self---addressed container is to be
supplied by your Sullair dealer at start ---up. The
user will receive an analysis report with recommen-
dations.
Fluid is injected into the compressor unit in large
quantities and mixes directly with the air as the ro-
tors turn, compressing the air. The fluid flow has
three basic functions:
1. As coolant, it controls the rise of air temperature
normally associated with the heat of compres-
sion.
2. Seals the leakage paths between the rotors and
the stator and also between the rotors them-
selves.
3. Acts as a lubricating film between the rotors al-
lowing one rotor to directly drive the other, which
is an idler.
After the air/fluid mixture is discharged from the
compressor unit, the fluid is separated from the air.
At this time, the air flows through an aftercooler and
separator then to your service line while the fluid is
being cooled in preparation for reinjection.
2.4 COMPRESSOR COOLING AND LUBRICATION
SYSTEM, FUNCTIONAL DESCRIPTION
Refer to Figure 2---2. The Cooling and Lubrication
System (air---cooled version) consists of a fan,
double shaft drive motor, radiator-- type after-
cooler and fluid cooler, full flow fluid filter, ther-
mal valve, and interconnecting piping and tub-
ing. For water---cooled models, two shell and tube
heat exchangers and a water-- flow regulating
valve are substituted for the radiator---type cooler
listed above.
The pressure in the receiver/sump causes fluid flow
by forcing the fluid from the high pressure area of
the sump to an area of lower pressure in the com-
6
NOTE
WARNING
!
pressor unit.
Fluid flows from the bottom of the receiver/sump to
the thermal valve. The thermal valve is fully open
when the fluid temperature is below 170_F (77_C).
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 170_F
(77_C), due to the heat of compression, the ther-
mal valve begins to close and a portion of the fluid
then flows through the cooler. From the cooler the
fluid flows to the main filter and then on to the com-
pressor 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. Prior to enter-
ing the compressor unit, this fluid is taken through
the fluid filter, thus assuring properly filtered lubri-
cant for bearing supply.
The fluid filter has a replacement element and an in-
tegral pressure bypass valve. A gauge on the in-
strument panel shows red when the filter needs
servicing. This gauge has a pressure setting lower
than that of the bypass valve. The gauge should be
checked with compressor running at full system
pressure.
Water---cooled versions of the compressor have a
water---flow regulating valve (not shown) which op-
erates to conserve water during periods of varying
load on the compressor. This same valve automati-
cally shuts off the water supply when the compres-
sor is shut down. In addition, water---cooled mod-
els have a water pressure switch to prevent opera-
tion with inadequate water pressure.
2.5 COMPRESSOR DISCHARGE SYSTEM, FUNC-
TIONAL DESCRIPTION
Refer to Figure 2---2. The compressor unit dis-
charges the compressed air/fluid mixture into the
combination receiver/sump.
The receiver has three basic functions:
1. It acts as a primary fluid separator.
2. Serves as the compressor fluid sump.
3. Houses the final fluid separator.
The compressed air/fluid mixture enters the receiv-
er and is directed against the internal baffle. 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 receiver/
sump. 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 bottom of the separator ele-
ment to the inlet region of the compressor unit.
Fluid collecting on the bottom of the separator is re-
turned to the compressor by a pressure differential
between the receiver and the compressor inlet. A