The last thread of the material port starts to be called the conveying section. The material here cannot be plasticized, but it must be preheated and compacted. In the past, the old extrusion theory believed that the material here was loose, and later proved that the material was actually solid. Plug, that is to say, the material here is squeezed like a solid plug, so as long as the completion of the transport task is its function.
The principle of single-screw extruder: when the second section is called the compression section, the volume of the groove is gradually reduced from large to large, and the temperature is to reach the degree of plasticization of the material. Here, the compression is generated by the conveying section three, where it is compressed to one. This is called the screw. The compression ratio -3:1, some machines have also changed, and the finished plasticized material enters the third stage.
The principle of single-screw extruder: The third section is the metering section where the material maintains the plasticizing temperature, just the accurate and quantitative delivery of the melt material as the metering pump is supplied to the machine head. At this time, the temperature cannot be lower than the plasticizing temperature. Slightly higher.
The single-screw extruder is mainly used for extruding soft plastics such as soft and hard polyvinyl chloride and polyethylene. It is matched with the corresponding auxiliary machine (including the forming machine head) to process a variety of plastic products, such as membranes and tubes. Plates, ribbons, etc., can also be used for granulation.