| Problem | Possible causes | Solutions |
|---|---|---|
| The film is not sticky enough | The base resin may contain an opening agent and a slip agent | Choose the resin without opening and smooth agent; the density is less than 0.923. |
| The inflation ratio is too small | Recommended inflation ratio: 2.5-3. | |
| The cooling air temperature is too high | 1) reduce the cooling air temperature, or increase the air volume. The cold air outside the factory is used in winter; the air is cooled by air-conditioning in summer and then used again. 2) increase the height of the traction roller as much as possible and increase the cooling time of the film bubble. 3) adding the inner cooling device of the membrane bubble. | |
| The processing temperature is too low | The head temperature should be higher than 220 ° C. | |
The film does not have enough storage time | Tackifiers produce stickiness within 72 hours of production or longer (depending on storage temperature). | |
| The crystallinity of the film is too high | The tackifying layer can add 10% of the non-open lubricant LDPE to help tackifying agent PIB precipitation. | |
| Stretch film appears size head | PW60 & PW66 high dosage, membrane volume storage room temperature is high and poor ventilation | 1) the PIB precipitates easily in summer, and the viscosity-increasing dose is 2% less than that in winter. 2) the recommended temperature of the film coil storage room is 7 ° C-30 ° C. 3) the film roll should be stored on the pallet, and pay attention to keeping ventilated. |
| Too tight or too loose tension in winding | Adjust winding tension to moderate | |
| PW60 & PW66 high volume film volume standing storage | Change the storage mode when the amount of tackifier is high | |
| The film rolls are too thick | Reduce winding length to a minimum (500M) | |
| Rewinding | ||
| Poor transparency | The dispersion of tackifier in LLDPE is not good | Raise the melt temperature |
| The processing temperature is too low | Raise the processing temperature | |
| The cooling air temperature is too high | Reduce the cooling air temperature, increase the airflow, or add a bubble cooling device | |
| Add 10% or more of LDPE without an open-mouth lubricant. |
