Mother Baby/ Two Stage Granule Making Machine

A vented or two-stage screw is essentially two screws on the same shaft. The first works as a conventional screw by feeding, melting, and conveying the polymer forward. The second screw does the same, except it is melt-fed by the first screw. The first screw operates with no head pressure, while the second has to overcome any head pressure from the die and other downstream components.

Vented extruders are significantly different from non-vented extruders in design and in functional capabilities. A vented extruder is equipped with one or more openings (vent ports) in the extruder barrel, through which volatiles can escape. Thus, the vented extruder can extract volatiles from the polymer in a continuous fashion.

This devolatilization adds a functional capability not present in non-vented extruders. Instead of the extraction of volatiles, one can use the vent port to add certain components to the polymer, such as additives, fillers, reactive components, etc. This clearly adds to the versatility of vented extruders, with the additional benefit that the extruder can be operated as a conventional non-vented extruder by simply plugging the vent port and, possibly, changing the screw geometry.

Operation capacity: 1000 kg/Hr