All kinds of pollutants, exist in the hydraulic system of the oil when excavator assembly, will remain in the chip components and piping, rust scale, rubber particles, such as a variety of external contamination.
When the system in the process of cast parts wear and oil from the physical and chemical products belong to the internal contamination.
These pollutants light to accelerate element wear and scratches the seals, affect the system's performance and service life, or blocking orifice, stuck valve class element, element action failure so that damage.
It's safe to say there is no absolute clean oil!
But in order to guarantee the normal work of the hydraulic system of the life, must be on particle size and quantity of pollutants in the system to be controlled.
The function of the filter is to purify oil ceaselessly, make its pollution control in the permitted range.