How to adjust the parameters of the Exhaust Screw Of The Extruder according to the material characteristics?

1. Understand the material characteristics
First, it is necessary to understand the physical and chemical properties of the material to be extruded in detail, including the viscosity, melting temperature, gas content, thermal stability, fluidity, etc. of the material. These characteristics will directly affect the working state and required parameters of the exhaust screw.

2. Adjust the speed of the exhaust screw
Low viscosity material: For materials with lower viscosity, the speed of the Exhaust Screw Of The Extruder can be appropriately increased to increase the shear force and mixing effect and promote the discharge of gas.
High viscosity material: For materials with higher viscosity, the speed of the Exhaust Screw Of The Extruder should be appropriately reduced to avoid excessive shearing of the material in the screw and generating too much heat, causing the material to degrade or burn.
3. Adjust the screw temperature
Melting temperature: According to the melting temperature of the material, adjust the temperature of each section of the exhaust screw. Ensure that the material can be fully melted in the screw, but will not be degraded due to excessive temperature.
Exhaust section temperature: The temperature of the exhaust section should be appropriately higher than that of other sections to promote the volatilization and discharge of gas. But too high a temperature may also cause material degradation, so a balance needs to be found.
4. Adjust the screw structure and exhaust design
Screw diameter and aspect ratio: Select the appropriate screw diameter and aspect ratio according to the characteristics of the material and the extrusion requirements. A larger screw diameter and a longer aspect ratio can provide stronger shear force and mixing effect, but it will also increase the energy consumption and cost of the extruder.
Vent hole design: Optimize the position, number and size of the vent holes to ensure that the gas can be discharged smoothly without affecting the extrusion process of the material. The design of the vent hole should fully consider the fluidity and gas content of the material.
5. Consider other factors
Extrusion pressure: Adjust the extrusion pressure according to the fluidity and extrusion requirements of the material. Appropriate pressure can ensure that the material is fully compressed and plasticized in the screw, but excessive pressure may also cause material degradation or extruder overload.
Screw gap: Ensure that the gap between the screw and the barrel is appropriate to avoid material leakage and extrusion instability. The size of the gap should be determined according to the characteristics of the material and the design of the extruder.
6. Actual debugging and verification
After adjusting the parameters of the exhaust screw, actual debugging and verification are required. By observing the flow state of the material, the exhaust effect and the quality of the extruded product during the extrusion process, the parameter settings can be further adjusted and optimized.