Air Flow; Oil System - Atlas Copco XAMS 1150 CD7 T3 APP Instruction Manual

Reference Name
OLG Oil Level Gauge
OS Oil Separator
OSV Oil Stop Valve
PS Pressure Sensor
RPS Regulating Pressure Sensor
RV Regulating Valve
SC Safety Cartridge
SL Scavenge Line
SV Safety Valve
TBV Thermostatic Bypass Valve
TS Temperature Sensor
TV Throttle Valve
UA Unloader Assembly
VH Vent Hole
VV Vacuator Valve
WPG Working Pressure Gauge
WPS Working Pressure Sensor

AIR FLOW

Air drawn through the airfilter (AFce) into the
compressor element (CE) is compressed. At the
element outlet, compressed air and oil pass into the air
receiver/oil separator (AR/OS).
The check valve (CV) prevents blow-back of
compressed air when the compressor is stopped. In
the air receiver/oil separator (AR/OS), most of the oil
is removed from the air/oil mixture.
The oil collects in the receiver and on the bottom of
the separator element.
The air leaves the receiver via a minimum pressure
valve (MPV) which prevents the receiver pressure
from dropping below the minimum working pressure,
even when the air outlet valves are open (specified in
section Limitations). This ensures adequate oil
injection and prevents oil consumption. The
minimum pressure valve (MPV) also functions as a
check valve.
The system comprises temperature sensors (TS),
pressure sensors (PS) and a working pressure sensor
(WPS).

OIL SYSTEM

The lower part of the air receiver (AR) serves as an oil
tank.
Air pressure forces the oil from the air receiver/oil
separator (AR/OS) through the oil cooler (OC), the oil
filters (OF) and the oil stop valve (OSV) to the
compressor element (CE).
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When the compressor is stopped and / or there is no
pressure in the system, the oil stop valve (OSV)
prevents the oil from flowing back into the
compressor element.
The thermostatic by-pass valve (TBV) starts opening
when the oil temperature is 80°C (176°F).
The compressor element has an oil gallery in the
bottom of its casing. The oil for rotor lubrication,
cooling and sealing is injected through holes in the
gallery.
Lubrication of the bearings is ensured by oil injected
into the bearing housings.
The injected oil, mixed with the compressed air,
leaves the compressor element and re-enters the air
receiver, where it is separated from the air as
described in section Air flow. The oil that collects on
the bottom of the oil separator element is returned to
the system through a scavenging line (SL), which is
provided with a flow restrictor (FR).
The oil filter by-pass valve opens when the pressure
drop over the filter is above normal because of a
clogged filter. The oil then by-passes the filter
without being filtered. For this reason, the oil filter
must be replaced at regular intervals (see section
Preventive maintenance schedule).