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5 | Setting up / assembly / integration of the filter unit
HYDAC FILTER SYSTEMS GMBH
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MoWa OF5 S_N 3160336d en-us lq
5.3 Avoiding the mixing of oils - Emptying the filter unit
If you want to use the same oil for operation as in the previous
operation, it is not serious if the oils are mixed.
If you do not know which oil was previously filtered with the fil-
ter unit, replace the filter element and empty the filter unit com-
pletely in order to prevent mixing with the residual oil in the fil-
ter unit.
If different oils are mixed, the oil properties can change as fol-
lows:
– Higher risk of cavitation
– More seal wear
– Modified anti-wear properties
– Poorer filtration
– Reduced filter element service lives
– Modified friction characteristics
– Modified response to water
– More deposits due to additive reactions
– More system contamination due to dissolved deposits
– Modified water/air uptake and output properties
– Greater tendency to foam