Applications involving transportation of plastic material, such as polystyrene beads, the wafer type design is the preferred sensor. The wafer type (figure 6) is available in a variety of different pipe sizes, ranging from 40 mm to 250 mm in pipe diameter.
Major advantage of this method is that the sensors are actually integrated within the spool piece.
Some coating with dirt or other substances of the internal surface will have little or no effect on the accuracy and reliability of the analysis. Basically, the internal surface and shape of the sensor exactly matches the surface and shape of the piping system in which it is installed, reducing the risk of fouling. This feature is again a major advantage compared to other inline analyzers, where the sensing device is often susceptible to layer formation.