The root cause of the wrinkles in the film of the blown film machine is the uneven thickness of the film, even if it is very small. After accumulation, it can cause obvious wrinkles, which affects the measurement data of the drop test, film tear test, and film friction coefficient .
Solution:
1. Lowering the melt temperature can effectively reduce the melt fluidity, and it is more sturdy when the die is extruded, and the film bubble is not skewed due to cooling air, which causes uneven cooling of the film.
2. Reduce the cooling air volume or mediate the cooling air unevenness.
3. The angle of the herringbone is too large, which makes the film flattened in a short time, so the problem of wrinkles occurs. The angle of the herringbone should be appropriately reduced.
4, the film extrusion is not uniform, the die should be adjusted so that it is in a vertical state.
5. The tension of the take-up roller is too large to pull the film. The tension of the take-up roller should be appropriately reduced.
