Thickness variation is one of the most expensive hidden losses in PET/PP sheet extrusion. Root causes concentrate in unstable feeding, inconsistent melt temperature, die-lip imbalance, and insufficient measurement feedback.
A process-first approach helps operators avoid correcting the wrong stage. For demanding packaging applications, thickness variation should be kept within roughly ±3% to ±5% of target.
"Stable gauge control is not merely a process detail — it directly protects downstream profitability."
Integrating a melt pump between the extruder and die improves flow control precision to ±0.5% and reduces thickness tolerance to ±1%–±2%, while also lowering screw backpressure by 30–50% and cutting line energy consumption by 10–15%. This directly protects downstream thermoforming yield and long-term profitability.
