Working principle of laboratory extruder

The working principle of laboratory extruder mainly includes the processes of material conveying, plasticizing, mixing and molding. Laboratory extruders usually use single-screw extruders, and their working principle is as follows:

● Material conveying: The material is added to the feed section of the extruder from the feed port. Under the action of the rotating screw, the material is conveyed and compacted forward by the friction between the inner wall of the barrel and the surface of the screw. Since there is a heating ring outside the barrel, the heat is transferred to the material through the barrel, and the material generates friction heat during the forward process, causing its temperature to gradually increase.

● Plasticization and mixing: The material enters the plasticizing section under the push of the screw, and is gradually melted and plasticized by the shear force and friction force of the screw, as well as the heating of the external heating system. The screw thread shape and pitch design help to mix and plasticize the material. During the plasticizing process, the material is continuously mixed, plasticized and conveyed in the screw thread groove.

● Molding: The plasticized and mixed materials finally reach the molding section, where they are extruded through a mold under a certain pressure and temperature to form a continuous product of the desired shape. The molded product is cooled and shaped by a cooling device (such as a water tank, air cooling, etc.), and then cut or rolled by a traction device.