Analysis of common faults of film blowing machine

news1. Bubble film is unstable
The extrusion temperature is too low and the amount of discharge is small;
Solution: adjust extrusion temperature;
It was interfered and influenced by strong external air flow.
Solution: prevent and reduce the interference of external airflow.
The air volume of cooling air ring is not stable, and the cooling of bubble film is not uniform;
Solution: Check the cooling air ring to ensure uniform air supply around;
Extrusion temperature is too high, the fluidity of the fused resin is too large, the viscosity is too small, easy to produce fluctuations;
Solution: Adjust extrusion temperature;

2. The heat sealing of the film is poor
If the dew point is too low, the polymer molecules will be oriented, so that the performance of the film is close to that of the oriented film, resulting in the reduction of the heat sealing performance;
Solution: Adjust the size of the air volume in the ring, make the dew point higher, as far as possible under the melting point of plastic blowing and traction, in order to reduce the molecular stretching orientation caused by blowing and traction;
If the blowout ratio and traction ratio are inappropriate (too large), the film will have tensile orientation, which will affect the thermal sealing performance of the film.
Solution: blowing ratio and traction ratio should be appropriately small, if blowing ratio is too large, and traction speed is too fast, the horizontal and longitudinal tensile of the film is excessive, then it will make the performance of the film tends to be bidirectional tensile, film heat sealing will become worse.

3. The surface of the film is rough and uneven
The extrusion temperature is too low, the resin plasticization is bad;
Solution: Adjust the extrusion temperature setting, and appropriately increase the extrusion temperature, to ensure that the resin plasticized well.
The extrusion speed is too fast.
Solution: Reduce extrusion speed appropriately


Post time: Mar-13-2023