Blown Film Extrusion Troubleshooting Guide


Five-layer Co-extrusion Blow Film Machine

When troubleshooting blown film extrusion machines, it is important to follow a systematic approach to identify and resolve the problem. In this guide, we will discuss common steps to follow when you encounter a blown film extrusion problem and need to troubleshoot:

  1. Identify the problem: Start by observing the extrusion process and identifying any signs of trouble, such as uneven film thickness, poor surface quality, or abnormal noises.
  2. Check the equipment: Inspect the equipment for any obvious signs of damage, wear, or malfunction. Check the temperature settings, pressure gauges, and other parameters to ensure they are within the recommended range.
  3. Review the process parameters: Review the process parameters, such as extrusion speed, die gap, and cooling airflow, to ensure they are set correctly for the material being used.
  4. Collect data: Collect data on the process parameters and the quality of the extruded product using sensors, gauges, and other tools. This data can help identify the root cause of the problem.
  5. Analyze the data: Analyze the data to identify any trends or patterns that could indicate the cause of the problem. Look for correlations between process parameters and quality issues.
  6. Make adjustments: Based on the data analysis, make adjustments to the process parameters as needed to correct the problem. This may involve adjusting the die gap, changing the cooling airflow, or adjusting the temperature settings.
  7. Monitor the results: Monitor the results of the adjustments and check the quality of the extruded product to ensure the problem has been resolved.

The most difficult is Identifying the Problem in Troubleshooting

Among the troubleshooting steps above, the most difficult one is identifying the problem that requires practical technical experience in blown film extruders to be easier to achieve,  below we will discuss several of the more common problems in the blown film extrusion process and provide solutions to help you maintain consistent output:

  • Excessive Die Lip Buildup: Die lip buildup is a common issue that may occur during blown film extrusion. The buildup can result in uneven film thickness and can cause the film to tear during the winding process. To prevent this issue, it is essential to clean the die lip regularly using a non-abrasive cleaning agent. If the buildup is significant, disassemble the die and clean it thoroughly before reassembling it.
  • Excessive Motor Load: Excessive motor load is another common issue in blown film extrusion, which can result in poor film quality and decreased output. The primary cause of this issue is often an improper melt temperature. To resolve this problem, monitor the temperature and adjust the heating zones to maintain a consistent temperature.
  • Poor Film Quality: Poor film quality can be caused by various factors, including an insufficient cooling rate, incorrect film thickness, or impurities in the resin. To resolve this issue, ensure that the cooling time is sufficient, adjust the film thickness, and ensure that the resin is clean and free of impurities.
  • Uneven Film Thickness: Uneven film thickness can result in poor product quality and is often caused by issues with the cooling system or extrusion conditions. To resolve this problem, ensure that the cooling system is functioning correctly, adjust the extrusion conditions to maintain consistent output, and use proper equipment for the desired thickness.
  • Poor Winding Quality: Poor winding quality is another issue that may arise during blown film extrusion, resulting in decreased output and poor product quality. The primary cause of this issue is often improper winding tension. To resolve this problem, adjust the winding tension and ensure that the winding roll is free of defects.


In conclusion, blown film extrusion troubleshooting requires careful attention to detail and a thorough understanding of the process. By following the tips outlined in this guide, you can maintain optimal performance and production of your blown film extrusion machine. If you encounter any issues not covered in this guide, consult your machine's manual or contact a professional technician for assistance.

At PLASTAR Machinery, we prioritize providing our customers with the highest quality products and services. We hope this guide has been helpful in troubleshooting blown film extrusion issues and improving the efficiency and quality of your production process. If you have any blown film extrusion machine needs or questions, welcome to contact us!