Dalian extrusion molding is also called extrusion in plastic processing. In non rubber extruder processing, it uses hydraulic press pressure to extrude the die itself. It refers to a processing method in which materials are heated and plasticized while being pushed forward by the screw through the action between the extruder barrel and the screw, and continuously pass through the machine head to make products or semi-finished products with various sections. It carries out solid transportation, compaction, melting, shear mixing and extrusion of plastics through external power transmission and heat transfer of external heating elements. Since the birth of screw extruder, after nearly 100 years of development, it has developed from ordinary screw extruder to new screw extruder.
Although there are many kinds of new screw extruders, the extrusion mechanism is basically the same. The extrusion process of traditional screw extruder is realized by external heating, solid material and barrel, screw friction and melt shear force. Friction coefficient and friction, viscosity and shear stress are the main factors affecting the working performance of traditional screw extruder. Due to the complex factors affecting friction and viscosity, the extrusion process of traditional screw extruder is an unstable state and difficult to control, especially for some heat sensitive plastics with poor thermal stability and high viscosity.
Since the 1960s, scholars all over the world have done a lot of research on the screw extrusion mechanism and made obvious achievements. However, most of their research is limited to the traditional plastic extrusion mechanism, mechanical structure and energy exchange mode, so they have not made a major breakthrough. A series of shortcomings of traditional screw extruder, such as large volume, high energy consumption, high noise and difficult to improve product quality, have not been fundamentally solved.