Micromeritics ACCUPYC II 1345 Operator's Manual page 67

Analysis Conditions (continued)
Field or Button
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Where P1 is the initial pressure to which the sample is charged, and P2 the final pressure after
expansion.
AccuPyc II 1345 Operator Manual
134-42851-01 (Rev -) — Not Released
Description
sample to the necessary size and shape. This is accomplished by
using either the average cell diameter or the cell chord length (as
defined in ASTM method D-6226-15) and the measurements of
the sample to determine the volume of the cut cells. This volume
is deducted from the total volume of the open cells measured by
the pycnometer.
Correction by recutting sample. Corrects for the cut cells by
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using two separate measurements. For the 2nd measurement,
the sample is recut to double the amount of cut surface. The
observed difference in cut open cell volume is applied as a cor-
rection to the initial measured volume. This method offers the dis-
tinct advantage that no assumptions are needed about the
relative amounts of open and closed cells.
No correction. Does not correct for cut cells. It is used for mater-
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ials with predominantly open cells where good accuracy can be
achieved without correction. The accuracy level deteriorates as
the percentage of closed cells increases.
Enter the initial and final pressure, and the pressure increment.
Compressibility test. The fill pressure is increased incre-
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mentally over the sample with each repeat of the P1,P2
The apparent variation of the measured sample volume with the
average pressure is determined. This test is an approximate indic-
ation. It is not intended to be an exact measure of the volume com-
pressibility.Where P1 is the initial pressure to which the sample is
charged, and P2 the final pressure after expansion.
Enter the Low pressure and the Fracture pressure.
Cell fracture test. A perfectly rigid foam is assumed. First, a
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P1,P2 cycle is performed at the lower of two specified P1 pres-
sures, and the results stored. A second cycle is performed at a
higher specified value of P1, then a third cycle identical to the first
cycle is performed. The difference between the volume of the
sample on the first measurement and on the third measurement
is reported as the volume of fractured cells. It is assumed that
cells fracture by exposure to the highest pressure (2nd cycle) so
that when the third measurement is made, the measured sample
Analysis Conditions
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cycle.
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