OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: 832-320-7300 / Fax: 713-880-9886 / www.ofite.com
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Hold a rag or piece of paper over the valve stem in order to catch any
liquid or solids that might be ejected under pressure from the cell. This will
help prevent an unsightly residue build up on the ceiling which may occur
over time. It may be necessary to return the cell to the heating jacket and
use the stop-pin in order to loosen the valve stem.
Pressure should NOT be relieved from the cell by opening the outlet valve
stem as the filter cake may seal off the cell.
A good indication that pressure is trapped inside the cell body occurs if
the set screws are unusually difficult to loosen (especially the 4th, 5th,
and 6th ones) and the cell cap begins to extrude out of the cell body as
the set screws are progressively loosened. To relieve any trapped pres
-
sure, an OFITE Pressure Relief Tool (#170-91) may be inserted through
the inlet cell cap hole which will relieve any trapped pressure inside the
cell. Ensure this function is performed on the inlet side of the cell as the
filter cake may seal off the outlet end of the cell.
32. Loosen, but do not remove, the six cap locking screws, and separate the
cap from the cell with a slight rocking motion. The OFITE Cell Cap Re
-
moval Tool (#170-33) makes it easy to remove tight, difficult to remove,
cell caps which may have slightly heat expanded.
33. There are several ways to remove the filter along with the filter cake.
a. Hold the cell and invert it over a sink and let the weight of the fluid
inside the cell push the disk out.
b. Careful manipulation with a spatula will often remove a filter and filter
cake intact without losing fluid.
34. Discard the fluid inside the cell unless it is required for further testing.
Save the filter cake for analysis.
35. Clean and dry the apparatus thoroughly after each use.
36. Inspect all o-rings for deformities and replace as necessary. Replace all
o-rings if the test was conducted above 350°F (177°C).
After each test, the HTHP filter press should be left so that a new test may be
performed with no clean-up and a minimum of assembly.
Safe Release
of Pressure
from a Cell
