The COLLIN pressure filter test is used for determining quality differences in a polymer caused by agglomerates, insufficiently dispersed fillers resp. contaminations.
A filter cassette in pre-heating position enables a quick and clean manual filter change without stopping the extruder. During the filter change, the melt is diverted via a bypass valve in front of the filter.
The material to be tested is melted in an extruder, homogenized and guided through a screen via a melt pump with a defined and constant volume flow. Particles of a certain size are caught in the screen and the available surface is decreased, increasing the pressure, measured by a transducer, in front of the screen.
