The working principle of the plastic extruder

     Plastic screw extruder is one of the main device for plastic processing. It through heat transfer from the external power delivery and external heating element to achieve the aim of solid conveying, compaction, melting, shear mixing extrusion molding. Since the beginning of the screw extruder, after a hundred years of development, the ordinary screw extruder has developed into a new novel screw extruder. Although there are many different kinds of novel  screw extruder, the extrusion mechanism is bassically the same.The processing of traditional screw extruder extrusion is depend on barrel outer heating, solid materials and the barrel, screw friction and the melt shear force. Friction coefficient and friction, viscosity and shear stress are the main factors influence the feature of the traditional screw extruder . Because the influencing factors of the friction and viscosity is very complicated, as a result, the traditional screw extruder extrusion process is an unsteady state, hard to handle, especially for some poor thermal stability, high viscosity of heat-sensitive plastic. Since 1960’s,a large number of studies about the screw extrusion mechanism have been perfomed by the the scholars from all over the world,and has achieved obvious results. But as a result of their research are mostly limited to the traditional plastic extrusion forming mechanism, mechanical structure and type of transducer, but ongreat breakthrough has been made now. The prodlems of traditional screw extruder , such as large gargantuan of immense size, high energy consumption, noisy machine work,hard to improve the product quality, and so on.These problems have not still gotten basic settlement.