Parallel co-rotating twin screw extruder is normally made up of two-stage extruder. It can make wood flour dry and resin melting procession separate. Besides, it also can operate wood flour and plant fibers directly and then continually mix and extrude wood flour with the melting resin after wood flour is dried.
This kind of two-stage extruder can be called as “extruder for wood”. Although this kind of two-stage extruder can dry wood flour, it has certain requirement for water contention, normally 4% to 8 %( mass fraction). Another form is similar to this one. Wood flour is added into the main charging hole of extruder and the front part of the extruder is the dehydration equipment, and then add the plastic resin and additive through the side feed device so that the screw of extruder is relatively longer .
Parallel co-rotating twin screw extruder can be described as the “mixed-type ”equipment with high speed, high energy consumption in wood processing industry, and normally it is modular –screw, which can adjust the length-diameter ratio and configuration, and set the exhausting hole freely.