1. Common Faults and Symptoms

1. Uneven Thickness

   • Inconsistent die temperature or unstable pressure

   • Inadequate plasticizing or irregular haul-off speed

   • Lack of real-time thickness monitoring and feedback loop                  

2. Surface Gels/Black Dots

   • Improper drying or poorly dispersed additives

   • Dirty filters or screw contamination

3. Melt Break / Drawn Threads

   • Melt temperature too low or pressure fluctuation

   • Wrong material ratio or excessive shear speed

4. Bubbles / Wrinkles

   • Moisture in raw material or foaming agent residues

   • Cooling roll temperature mismatch or line speed imbalance

5. Tension Instability / Creases

   • Lagging tension feedback or no closed-loop control

   • Winder tension not matching current film thickness/speed

6. Gel Spots / Flow Marks

   • Localized overheating at die or non-uniform melt flow

   • Poor screw mixing performance or material segregation

3. Optimization Tips

• Install online thickness scanners to enable real-time feedback adjustment

• Use multi-zone PID temperature control for melt flow consistency

• Clean screws/barrels regularly, and replace filters as scheduled

• Balance chill roll temperature and line speed to avoid ripples or shrinkage

• Implement closed-loop tension control to optimize winding conditions

• Activate smart alarms to detect pressure, temp, or tension irregularities

Conclusion:

Most EVA extrusion issues can be resolved through careful tuning of temperature, tension, material formulation, and die control. Choosing equipment with intelligent monitoring and closed-loop systems—and maintaining strict operational standards—is key to ensuring high-efficiency and stable solar film production.