What are the advantages of conical twin screws in processing high-temperature and high-viscosity materials?

1. High torque and large load capacity, adaptable to extreme working conditions

The transmission system of the conical twin screw adopts a large-diameter thrust bearing design, which can withstand higher axial pressure and torque, especially suitable for the huge head pressure (usually up to 14-30MPa) generated in the processing of high-temperature and high-viscosity materials (such as PVC and rubber). Its conical screw structure makes the shaft diameter of the drive end larger, and the gearbox load capacity is significantly better than that of the parallel twin screw, which effectively avoids equipment overload caused by the resistance of high-viscosity materials.

2. Optimized shear and temperature control to reduce material degradation

Low shear rate design: The tapered twin screw groove depth gradient structure (gradually shallower from the large end to the small end) reduces the shear rate, avoids local overheating of high-viscosity materials due to excessive shearing, and reduces the risk of thermal decomposition of heat-sensitive materials (such as PVC and bio-based plastics).
Precise temperature control capability: The barrel heating system cooperates with the screw core oil circulation constant temperature technology to accurately control the melt temperature in the range of 180-190℃ to prevent the degradation of material performance under high temperature.

3. Efficient exhaust and plasticization uniformity

Self-cleaning and exhaust performance: The thread design of the meshing area allows the material to be continuously renewed on the surface of the exhaust section, effectively discharges volatiles (such as moisture, decomposition gas), and ensures the purity of high-viscosity melt.

Forced conveying and mixing: The compression ratio of the conical screw (usually more than 3:1) and the progressive thread geometry enhance the forced material conveying and mixing effect, and can achieve uniform plasticization even when processing highly filled materials (such as glass fiber reinforced plastics).

4. Wear-resistant and long-life design

Surface strengthening treatment: The screw adopts nitrided steel (such as 38CrMoAlA) or dual alloy coating (iron-based/nickel-based), the surface hardness can reach HV900-1100, and the nitriding depth is 0.5-0.8mm, which significantly improves the wear resistance and corrosion resistance, and prolongs the service life under high temperature and high wear conditions.
Easy maintenance: The split barrel design allows fast opening and closing for cleaning, reducing downtime, especially suitable for production scenarios where frequent color or formula changes are required.

5. Wide adaptability and extended application

The conical twin screw is not only suitable for traditional PVC hard products (such as pipes and profiles), but can also be extended to the processing of high-temperature engineering plastics (such as PC, PMMA) and high-filling materials (such as carbon fiber reinforced composites) by adjusting the screw combination and process parameters. Its stable extrusion force and temperature uniformity support the efficient production of complex formulas