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5.5. Typical flow
The compressor oil flow is controlled by two thermostatic bypass valves, ensuring reliable compressor operation and
optimum energy recovery.
Figure 2: Example of air cooled oil injected screw compressor
7. 1
st
bypass valve of ER (BV1)
8. Heat exchanger of ER
12. Oil separator
14. 2
nd
bypass valve (BV2) of oil filter
pipe
23. Main oil cooler
24. Oil filter of oil filter pipe
25. Compressor element
The 1st bypass valve (Figure 2-7) is integrated in the ER unit and controls the operation of the oil heat exchanger (Figure 2-
8) of the ER unit. The 2nd bypass valve (Figure 2-14) is integrated in the oil filter pipe and controls the operation of the main
oil cooler (Figure 2-23) of the compressor. Both bypass valves consist of an insert (thermostat) mounted in a housing. In the
1st bypass valve of the ER unit, this is a single housing. In the 2nd bypass valve of the compressor, this housing is
integrated in the oil filter pipe (Figure 2-14).