|
|
|
|
 |
Contamination
is still the main reason for trouble and
down times of a hydraulic system. Contamination
is already created during the manufacturing
the components and in addition the fluid
has basic contamination. During operation
of the system further contamination is
created by abrasion and seal material.
Filters in a hydraulic system have to
reduce this contamination to an acceptable
level. Thus by filter, conditions are
created for a trouble free and low-maintenance
operation.
A
hydraulic filter consists of the element,
the housing and additional accessories
like by pass valve, contamination indicator,
reverse flow valve etc. The housing is
made up of the head and the bowl. The
element consists of the internal body,
the pleated star and the end plates. With
only few exceptions, the fluid flows in
filter -out- to- in.
|
|
|
|
|
The hydraulic filter needs additional
accessories like by pass valve and indicators.
Since operating pressure is high, it is necessary
to change the element (or clean the element
in case of re-usable) as soon it reaches its
limited differential pressure. To indicate the
same, indicator is required in the filter. Many
varieties of indicators are available - Visual
indicator & electrical indicator. Electrical
indicator gives indication by blowing the bulb
or alarm. If somebody ignore the indications,
it is obvious that the differential pressure
of filter will increase and in worst case filter
may burst! To avoid such situation, by pass
valve is required to by pass the fluid and protect
the filter. It is important that in such case,
un-filtered fluid will go in to the system.
|
|
FILTER CARTRIDGE : |
|
|
The
type of filter medium used is very important
for the success of hydraulic fluid and lubricant
filtration, particularly in the case of pressure
line filters for the most part, the type of
filter medium used are:
-
Impregnated Cellulose Paper
- Micro
fiberglass or
- S.S.
Wire Mesh.
|
SUCTION LINE FILTER :
|
 |
Suction
line filter are installed immediately
upstream of the pump to protect the pump
against all coarse contaminations. Since
pumps are very sensitive to low pressure,
large filter would have to be installed
to prevent the increasing differential
pressure at the filter from causing damage
to the pump. Hence coarser filter is generally
selected for suction line. Many times
only one side threaded and other closed
element is installed at the end of suction
line in to the tank.
|
FILTRATION IN THE SUCTION LINE |
PRESSURE LINE FILTER
: |
|
Pressure line filters must be installed
downstream of the pump and pressure relief
valve to protect upstream of the components.
If systems dose not aloud interruption,
we need to put duplex filter.
|
|
|
PRESSURE LINE FILTERS |
RETURN LINE FILTER :
|
 |
Return
line filters are those filters, which
are installed in the lines leading back
to the tank. The filter head is permanently
mounted to the tank and the outlet port
of the filter projects into the tank itself.
Return
line filters collect all those contaminants,
which are flushed out of the system and
not captured by pressure line filters.
|
RETURN LINE FILTERS |
DUPLEX FILTER :
|
|
For un-interrupted operations, duplex
filters are required in hydraulic system.
This is a sat of filter connected with
inter connecting valves to keep one as
a stand-by and one filter in operation.
|
|
|
SPIN-ON CARTRIDGE :
|
|
|
|
AIR BREATHER FILTER :
|
|
|
|
|
|
|
