3.5
[en] 02/2014
Installation and operating manual - NK 31
Figure 3-4
3.5 Flow diagram of NK 31
(pneumatic control unit)
3.6 Operating description for NK 31
Screw Compressor Compact Module
(pneumatic)
The flow diagram shows a schematic view of the
operating principle and the arrangement of the
main components of the NK 31 screw compres
-
sor module with pneumatic control unit, regard
-
less of any other equipment.
3.6.1 Standstill
At a standstill the intake valve
2
and the impulse-
pressure relief valve
3.2
are closed by the spring
pretension. The downstream devices are depres
-
surized.
The minimum pressure valve
7
is set to approx.
5
bar at the factory is tightly closed. The propor-
tional regulator
3.1
is set to operating pressure.
2.1
2
9
8
10
4
5
3
3.1
3.2
11
6
7
13
12
1
1. Intake filter
2. Intake valve
2.1 No-load nozzle
3. Control unit (pneumatic)
3.1 Proportional control valve
(positive)
3.2 Impulse-pressure relief valve
4. Screw compressor
5. Separator tank with pre-separation
6. Fine separator
7. Minimum pressure valve
8. Oil thermostat
9. Oil filter
10. Oil cooler
11. Air after-cooler
12. Non-return valve
13. Safety valve (optional)
