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Vol. 2.6 © 2020 Hanbell Precise Machinery Co., Ltd. All rights reserved
4.4 External oil filter
The external oil filter is a must in the oil circuit. It should be installed in the oil line after
the oil cooler. The function of external oil filters is to filter out debris so it does not act as
abrasive when oil re-circulates. The filter shell should be able to withstand oil pressure as
high as 12 to 15 bars.
Hanbell external oil filter must be used. Its filtering material could be cellulose (paper)
or synthetic fiber (15~25
μ
m). Paper can withstand flow of high-pressured oil without
being torn apart. The material has to be able to block small debris without restricting oil
flow too much. Cellulose (paper) as filter material is economical and works fine. Cellulose
as the filter may block particles while allowing oil to pass through. There is synthetic fiber
for high-end filters that has smaller passages to block smaller particles but still make fluid
pass it through. There is also a kind of material that is a blend of these two materials.
HANBELL provides oil filter with spec. below:
Working pressure
：
15bar
Working temperature
：
-20~100
℃
Filter accuracy
：
15~20
μ
m
Rated flow
：
100L/min
Note
：
The centrifugal compressor is of delicate type. It is a must to use above materials for
filtering.
Caution
：
If the filter material is a non-precision graded metal, the particles may get into
the compressor and cause serious damage to the bearings.
Caution
：
In addition to the pressure difference judging as a protection system program,
mechanical differential pressure switch can also be added as protection.
