# Identification and Judgment of Quality Differences in Three-Layer Co-Extrusion Film Blowing Machines

Quality of three-layer co-extrusion film blowing machines directly determines film uniformity, adhesion, performance and efficiency. Judgments rely on core components, process control, manufacturing, performance and after-sales service.

## 1. Core Components

- **Screw**: L/D 28–35, proper compression ratio, 38CrMoAlA nitrided alloy for wear resistance.

- **Die head**: Symmetrical spiral flow channels, 0.01mm adjustment precision, polished surface, optional automatic thickness control.

- **Drive**: Servo motors for stable output and energy saving.

## 2. Process Control Precision

- **Temperature**: PID control with fluctuation ≤±1℃.

- **Tension**: Closed-loop system to prevent wrinkling and deformation.

- **Automation**: PLC and HMI for parameter control and fault alerts.

## 3. Manufacturing and Assembly

- Heavy steel frame with stress relief treatment.

- CNC machined parts with high precision and good sealing.

## 4. Actual Performance

- Film thickness tolerance ≤±3%, stable lamination, qualified physical properties.

- Continuous stable operation with low failure rate and energy consumption.

## 5. After-Sales and Brand

- Professional installation, training and timely spare parts.

- Reliable brands ensure long-term stability.

## Conclusion

Comprehensive evaluation of configuration, control, manufacturing, performance and service is essential. Prioritize long-term stability over low price for better economic benefits.