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Because each system is unique, only a thorough testing and evaluation program can fully validate the
filtration system.
Please see
Design Guidelines for Hydraulic Fluid Cleanliness Technical Information
, BC152886482150 for
more information.
Filter β
x
-ratio is a measure of filter efficiency defined by ISO 4572. It is defined as the ratio of the number
of particles greater than a given diameter (“
x
” in microns) upstream of the filter to the number of these
particles downstream of the filter.
Filtration, cleanliness level and β
x
-ratio (recommended minimum)
Cleanliness per ISO 4406
22/18/13
Efficiency β
x
(charge pressure filtration)
β
15-20
= 75 (β
10
≥ 10)
Efficiency β
x
(suction and return line filtration)
β
35-45
= 75 (β
10
≥ 2)
Recommended inlet screen mesh size
100 – 125 µm
Service Manual
H1P 069—H1P 280 Axial Piston Single Pumps
Fluid and Filter Maintenance Recommendations
©
Danfoss | January 2021
AX152886482551en-000601 | 25