Prevention of adverse effects of mesh screen changer on extrusion molding

The screen changer (filter) is an automatic switching device consisting of one or more filters, which is used to filter out the particles and impurities contained in the plasticized material flow filter. The filter screen is supported by an alloy porous plate or wire mesh. The porous plate or wire mesh is installed on the carrier of the filter. The carrier is driven by hydraulic cylinder to switch between the working position of a system and the off-line non-working position.

The filter screen of the old plastic extruder is fixed on a porous or grooved protective plate, which can seal the screen changer and die of the extruder. The pressure generated by clean filter net is relatively small, which may only be 50 ~ 100lb/in2. With the increase of working time, the amount of impurities and particles in the material intercepted on the filter network increases, thus blocking the screen changer network in the filter.