6
3.0 Maintenance
A. When to Replace Filter Element
NOTE:
Grades 7,6,5,3,1 - complete element is re
-
placed; Grade 9 - unless separator core is damaged
outer sleeve only is replaced.
1. Grades 6 (dry desiccant afterfilter)
Initial drop: 1 psi (0.07 kgf/cm
2
). Pressure drop
increases as element loads with solid particles. Re
-
place when pressure drop reaches 10 psi (0.7 kgf/
cm
2
) (indicator in red area) or annually, whichever
occurs first.
2. Grade 11 (mechanical separator)
Element should not require replacement unless
physically damaged. If sludge accumulates, ele
-
ment can be removed and cleaned with soap and
water.
3. Grades 9, 7, 5, 3 (coalescing filters)
a. Initial (dry) pressure drop: 1 psi (0.07 kgf/cm
2
)
to 2 psi (0.14 kgf/cm
2
)
b. Operating pressure drop: As filter becomes liq
-
uid loaded (wetted), pressure drop will increase
to 2 to 6 psi (0.14 to 0.42 kgf/cm
2
). Further
pressure drop occurs as element loads with
solid particles.
FOR MAXIMUM FILTRATION EFFICIENCY, REPLACE
ELEMENT WHEN PRESSURE DROP REACHES 6 PSI (0.42
KGF/CM
2
) (INDICATOR IN RED AREA) OR ANNUALLY,
WHICHEVER OCCURS FIRST.
NOTE:
Pressure drop may temporarily increase when
flow is resumed after flow stoppage. Pressure drop
should return to normal within one hour.
NOTE:
Grades 5 and 3 - During normal operation
bottom of foam sleeve will have a band of oil.
Spotting above the band indicates that liquids are
accumulating faster than they can be drained and that
prefiltration is required.
4. Grade 1 (activated carbon filters)
a. Adsorption capacity - 1000 hours at rated
capacity. Element life is exhausted when odor
can be detected downstream of the filter.
SEAL PLATE
VESSEL
YOKE
NUT
GASKET
TILT THE SEAL PLATE
AND GASKET TO FIT IN OPENING
HAND HOLE
Handhole
O-RING
PLASTIC
SEAL RING
RETAINER
LOWER
BOTTOM
OF SHELL
Model 52
B. Procedure for Element Replacement
THIS FILTER IS A PRESSURE CONTAINING
DEVICE. DEPRESSURIZE BEFORE SERVICING.
1. By-pass the filter to permit
servicing.
2. Depressurize the filter as
-
sembly slowly by opening
blowdown valve.
3. Open pressure vessel
3A. Model 52 - Remove flange
bolts. Lower bottom
shell, o-ring, and seal ring
retainer.
3B. Models with handhole
a. Remove nut and yoke
b. Lift seal plate and turn so that seal plate and
seal plate gasket can be removed.
3C. Models with flanged bottom
a. Loosen bottom blind flange bolts.
b. Remove all but one bolt.
c. Swing flange to one side.
Bottom Flange
4. Starting in the center, unscrew the filter elements
and remove the filter elements and element o-
rings.
