Background and Challenges
A PBT modified plastic manufacturer's color masterbatch pellets reach temperatures as high as 120°C after drying. The conventional approach involves natural cooling before conveying, causing production line downtime due to waiting. Direct filling results in pellet clumping rates exceeding 10%, severely impacting product flowability and packaging quality.
Solution
A jacketed stainless steel screw conveyor was adopted, with the core innovation being the integration of conveying and cooling functions. The equipment features a double-layer 316L stainless steel structure, with circulating cooling water flowing through the jacket. As material is propelled by the screw blades, it undergoes thorough heat exchange with the cooling water via the pipe walls. Simultaneously, the screw shaft surface is coated with Teflon to reduce adhesion of high-temperature material and prevent sticking.
Application Results
This solution achieves simultaneous conveying and cooling, reducing material discharge temperature from 120°C to 40°C and lowering agglomeration rates from over 10% to 1.5%. It completely eliminates pre-packaging waiting time. First-pass yield increased from 85% to 98%, while packaging efficiency rose by 40%. Annual cost savings from reduced agglomeration scrap and rework exceed RMB 1.5 million, with equipment investment recouped in under six months.
Experience Summary
This case demonstrates that integrating conveying functions with process treatment in the plastic modification industry is an effective path to cost reduction and efficiency gains. The stainless steel screw elevator not only solves the challenge of conveying high-temperature materials but also simplifies production processes through functional integration, providing a replicable technical solution for similar high-temperature material handling applications.
