The Stereopycnometer is the standard model of the series of manually operated pycnometers. It offers a choice of two interchangeable sample cells used in conjunction with a single reference volume.
A sample is placed in the sample cell and degassed by purging with a flow of dry gas, by vacuum, or by a series of pressurization cycles. The analysis is performed by pressurizing the sample cell to approximately 17 psi and recording the value. The selector valve is rotated so the gas expands into the reference or added volume and that lower pressure is recorded. From these two readings the sample volume can be quickly and accurately calculated.
If samples are compressible foams, the cell-to-reference pressure sequence of the Stereopycnometer is the preferred method over that employed by the Multipycnometer.
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