Screw Feeder

A kind of feeder is always provided with extruders. As per different extrusion applications we have different options such as single screw feeder,  twin screw feeder, spring feeder, conical screw feeder, side feeder or volumetric feeder and loss-in-weight feeder (gravimetric feeder) etc.

This dual stage feeder is normally used to force raw material into the main twin screw extruder. The first stage feeder is VF control and the feeding rate can be adjusted. The second stage feeder constantly feeds additives into the main extruder through a side connection flange. So it's also called force feeder.

Gravimetric feeder is also called loss-in-weight feeder. It automatically balances the feeding rate as per the flowage of raw material in a certain time. So it features a better feeding accuracy, which is very important in some materbatch formulation.

All the feeders have screws, either single or double to push raw material, either in powder or in pellet into the next hopper, receiver or extruder. The different raw polymers requires different screw types to achieve a best output.