How does the choice of screw barrel material affect different plastics?

1. Matching Abrasion Resistance to Plastic Viscosity:
Different plastics have significantly different viscosities and abrasive properties. High-viscosity polycarbonate (PC) or glass fiber reinforced materials require hard alloy or nitrided screw barrels to reduce wear and extend screw life. Low-viscosity polypropylene (PP), on the other hand, can use ordinary alloy steel, offering a cost advantage.

2. Corrosion Resistance is Key for Specialty Plastics:
For plastics such as PVC and PA, which are susceptible to acid and alkali corrosion, selecting acid and alkali resistant alloys or surface coatings (such as chrome plating) can prevent screw barrel corrosion and ensure melt quality.

3. Thermal Conductivity Affects Melting Uniformity:
Materials with high thermal conductivity (such as aluminum alloys) can conduct heat more quickly, making them suitable for heat-sensitive plastics that require rapid heating; while materials with low thermal conductivity help control temperature rise and prevent the decomposition of heat-sensitive plastics.

4. Balancing Cost and Service Life:
In mass production, companies often need to balance material performance with cost. Zhoushan Microwave Screw Machinery Co., LTD offers screws and barrels in various materials, allowing customers to flexibly select the right type based on their product needs and budget.