How they work

Mann hummel centrifuge

How By-pass Centrifugal Oil Cleaners work


Full flow filters are designed to process all of the oil used to lubricate the moving parts of an engine. However, the need to maintain a high flow and limit pressure drop across the filtration media restricts the ability of full flow filters to remove fine contaminant particles. Thus, these filters act as a screen or barrier against the progress of large abrasive particles through the lubrication oil circuit, which may cause catastrophic failure.

The MANN+HUMMEL centrifugal oil cleaner operates in by-pass and processes approximately 10% of lube oil before returning it to the engine’s sump. The centrifugal oil cleaner is not a barrier filtration device and thus does not rely upon filtration media to remove contaminant particles. Removal of particles is based on relative density, henceforth, contaminant removal is not limited to particle size.

principle of operation

Oil is pumped into the centrifugal oil cleaner by the engine’s oil pump under pressure and directed into a hollow spindle where it exits via a cross-drilling  into the centrifuge rotor. The rotor becomes full of pressurised oil that is then allowed  to exit through two tangentially opposed  nozzles located in the rotor base.

This causes rotation of the free spinning rotor assembly, generating centrifugal forces within the rotor. As the contaminant particles enter the rotor, they are subjected to centrifugal force, causing them to migrate radically outwards to the inner surface of the rotor wall, where over  time, they compact to form a dense cake.

MANN+HUMMEL oil conditioning systems offer both cleanable and disposable rotor designs.