What is the difference between the single-screw and twin-screw extruders equipped with the torque rheometer?

Publish Time: 2025-01-14

As an indispensable equipment in materials science research and industrial applications, the type of extruder equipped with the torque rheometer has an important impact on the test results and practical applications. Among them, single-screw extruders and twin-screw extruders are two common configurations, which have significant differences in structure, working principle and application.

As the name suggests, the core component of a single-screw extruder is a spiral screw. The working principle of this extruder is relatively simple, and the material is mainly transported and plasticized by the rotation of the screw and the friction between the material and the screw and the inner wall of the barrel. The single-screw extruder is suitable for processing materials with low viscosity and good fluidity, such as some plastics and rubbers. It has a simple structure, easy operation and relatively low cost, so it is widely used in some occasions where the material processing accuracy is not high.

In contrast, the twin-screw extruder uses two intermeshing screws. This design makes the mixing and plasticization of materials during the extrusion process more significant. The screw structure of the twin-screw extruder is complex and can be divided into various types such as close meshing type and non-close meshing type, which can be flexibly adjusted according to the characteristics of different materials. Due to the interaction of the two screws, the material is subjected to stronger shearing and stretching during the extrusion process, thereby achieving more complete mixing and plasticization. This makes the twin-screw extruder perform well when processing high-viscosity, difficult-to-plasticize materials.

In addition, the twin-screw extruder also has higher production efficiency and better temperature control capabilities. Because the material is subjected to stronger shearing during the extrusion process, its molecular chain is more effectively interrupted and reorganized, thereby improving the plasticization quality and production efficiency of the material. At the same time, the barrel and screw surface of the twin-screw extruder are usually equipped with cooling water channels, which can achieve precise control of the material temperature and further improve the stability and controllability of the extrusion process.

In summary, there are significant differences in the structure, working principle and application of the single-screw and twin-screw extruders equipped with torque rheometers. Single screw extruders are suitable for processing materials with low viscosity and good fluidity, and have lower costs; while twin screw extruders are suitable for processing materials with high viscosity and difficult to plasticize, and have higher production efficiency and better temperature control capabilities. When choosing a torque rheometer, the appropriate extruder type should be selected based on the specific application requirements and material properties.