Sullair LS20T 1100 CFM, Operator'S Manual And Parts List

Page: 14 / 146

Section 2
DESCRIPTION
8
9.30 in the Parts List portion of this manual. The
compressor unit discharges the compressed
air/fluid moisture through a discharge check valve
into the combination receiver/sump. The discharge
check valve prevents air in the receiver from return-
ing to the compression chamber after the compres-
sor has been shut down. The receiver has three
functions:
• It acts as a primary fluid separator.
• Serves as the compressor fluid sump.
• Houses the final fluid separator elements.
The compressed air/fluid mixture enters the receiv-
er and is directed against the ends of the tank. 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 sur-
faces of the dual separator elements as the com-
pressed air flows through them. Two return lines (or
scavenge tubes) lead from the bottom of each sep-
arator element to the interstage of the compressor
unit. Fluid collecting on the bottom of each separa-
tor is returned to the compressor by a pressure dif-
ference between the receiver and the compressor.
Sight glasses are located in the return lines to
observe this fluid flow. There are also orifices in this
return line (protected by strainers) to assure proper
flow. By pressing the + pads on the
Supervisor Controller, the operator may monitor the
condition of the separator elements by reading dif-
ferential pressure on the digital display. At a differ-
ential of 10 psid (0.7 bar) or greater, the operator
will be told to service the separator element. At this
time, separator element replacement is necessary.
The receiver is an ASME pressure vessel. A combi-
nation minimum pressure/check valve, located
downstream from the separator, assures a mini-
mum receiver pressure of 160 psig (11 bar) during
full load operation. This pressure is necessary for
proper air/fluid separation and proper fluid circula-
Figure 2-2 Compressor Cooling, Lubrication and Discharge System (Typical)
KEY
A FLUID (LINE)
B AIR/FLUID (LINE)
C AIR (LINE)
D WATER (LINE)
E
MOISTURE
SEPARATOR
F TRAP DRAIN
G FROM AFTERCOOLER
H TO AFTERCOOLER
J FROM OIL COOLER
K
DISCHARGE CHECK
VALVE
KEY (CONTINUED)
L FROM UNIT
M
SUMP/SEPARATOR
TANK
N MAIN FLUID FILTER
P OIL STOP VALVE
Q
MINIMUM PRESSURE/
CHECK VALVE