Replacement of filter cartridges at your Oil Mist Separator

The special composition of our micro fibre cartridges guarantees high filter efficiency for a long period. But, why and when should the filter cartridges be replaced? Fine dust particles can be absorbed and enter with the oil mist into the cartridges thus clogging their micro fibre.

Taking a pressure gauge reading

Each Oil Mist Separator from FRANKE-Filter is equipped with a suitable side channel pump necessary for vacuum generation in the lube oil system. For the best separation of oil particles from crude oil it is essential to have the exact  vacuum which overcomes the resistance of the filter cartridges and maintains vacuum in the entire system constant.  With the help of the available pressure gauges U1 und U2 you can control the vacuum at any time.

After the initial commissioning of the separator or after replacement of filter elements it is necessary to adjust vacuum manually. The reason for this is due to low saturation and resistance of the filter elements. The pressure gauge U1 indicates vacuum in the system, whereas the pressure gauge U2 provides information on the current differential pressure (pressure difference before and after the filter cartridges). When the saturation level of filter cartridges increases the value of the U1 drops and U2 rises. In order to reach the necessary vacuum and thus an efficient separation level the admixed-air feed should be readjusted.

Replacing filter cartridges

During normal operation of the Oil Mist Separator the pressure gauge U1 is relevant for the determination of vacuum in the entire system.

The value of U2 is the indicator for the saturation level/contamination degree of filter cartridges. As soon as the value of the vacuum gauges reaches approx. 100 mbar, filter cartridges should be replaced in order to ensure failure-free operation and high separation efficiency for further 30,000 hours and even more.


Replacement of micro fibre filter elements is very simple. When the Separator is switched-off and disconnected from the mains, just the lid of the housing should be opened in order to take out the cartridges.

When replacing the elements and the supplied O-rings it is important to tighten the fixing grips just hand-tight. Too much pressure would compress the cylindrical body, whereas too little would mean that the cartridge lid and elements are not air-tight. When the Oil Mist Separator is put again into operation the operator responsible for the admixed-air ball valve should be again readjusted.