Fig. 5 General design
1
Compressor air filter
3
Inlet valve
4
Airend
5
Oil separator tank
7
Oil separator cartridge
10
Compressed air distributor
13
Pressure relief valve
14
Pressure gauge (on the instrument panel)
15
Engine
16
Oil return line
19
Combination valve (oil temperature thermo‐
stat)
20
Oil cooler
21
oil filter
23
Proportional controller
24
Engine air filter
27
Venting valve
28
Fan
37
Minimum pressure/check valve
52
Control valve
Ambient air is cleaned as it is drawn in through the filter
1
.
The air is then compressed in the airend
4
.
The airend is driven by an internal combustion engine
15
.
Cooling oil is injected into the airend. It lubricates moving parts and forms a seal between the rotors
themselves and between them and the airend casing. This direct cooling in the compression chamber
ensures a very low airend discharge temperature.
Cooling oil recovered from the compressed air in the oil separator tank
5
gives up its heat in the oil
cooler
20
. The oil then flows through the oil filter
21
and back to the point of injection. Pressure within
the machine keeps the oil circulating. A separate pump is not necessary. A thermostatic valve
19
regulates the compressor's temperature.
Compressed air, freed of cooling oil in the oil separator tank
5
, flows through the minimum pressure /
check valve
37
into the air distributor
10
. The minimum pressure / check valve ensures that there
is always a minimum internal pressure sufficient to maintain cooling oil circulation in the machine.
The cooling fan
28
ensures optimum cooling of all components within the enclosure.
4
Design and Function
4.3
Machine function
No.: 9_9425 01 E
Service Manual Screw Compressor
M170 SIGMA CONTROL MOBIL
29