70Xi Cold Flow Properties Laboratory Analyzer
User Guide
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As soon as the signal rises sufficiently, the analyzer displays the cloud point and completes the test by
warming the sample back to room temperature.
Freeze Point
Freeze point is the temperature at which solid hydrocarbon (wax) crystals disappear when the
temperature of a sample rises after having been previously cooled and allowed to form under conditions
prescribed by the ASTM D5972 test method.
During a freeze point test, Phase Technology’s 70Xi analyzer cools the sample relatively quickly until wax
crystals begin to form. On a freeze point phase plot, this can be seen as the blue line moves from left to
right. As the crystals form, the baseline rises.
After a sufficient number of crystals are present, the sample is warmed until they all disappear. This
warming phase is shown in green on the phase plot. Freeze point can be seen where the green curve
returns to a flat blue baseline, then stabilizing during the warming stage.
Pour Point
Pour point is the lowest temperature at which movement can still be observed as a sample is cooled and
perturbed under conditions prescribed by the ASTM D5949 test method.
