1. Raw material processing
Dry raw materials: ensure that the material has low water content to avoid bubbles or pinholes on the surface of the plastic bag film.
Adding additives: Add antifogging agents, antistatic agents or barrier additives as needed to improve film performance.
2. Process parameter control
Extrusion temperature: ensure that the molten plastic has good fluidity but does not decompose. The common temperature range is 150°C-250°C.
Blowing ratio: refers to the ratio of the diameter of the film bubble to the diameter of the die. A reasonable ratio should be selected according to the film performance requirements, usually 1.5:1 to 4:1.
Draft ratio: affects the mechanical strength and transparency of the film, and is usually controlled within a reasonable range.
3. Cooling ring uniformity
The cooling ring provides uniform cooling airflow to prevent the film bubble from deformation or inconsistent thickness due to uneven cooling.
4. Film bubble stability
Use a stabilizing frame to keep the film bubble stable to avoid shaking that affects the uniformity of film thickness and surface quality.
Thickness control
5. Online thickness gauge
Real-time monitoring of film thickness and adjustment of die gap or pulling speed to ensure consistent film thickness.
6. Impurity control
Avoid impurities in raw materials and clean equipment regularly to prevent black spots or film surface defects.
Environmental factors
The production environment needs to maintain constant temperature and humidity to avoid temperature differences or excessive air flow that affect the stability of the film bubble.
