Production process for stretch film
July 10, 2019
Stretch film is the most common production product of stretch film manufacturers, and it is also the most commonly used packaging material in our lives and in industry. However, many stretch film manufacturers do not understand the production process, which determines the quality of the stretch film.
Most of the stretched film produced by the former stretch film manufacturers mostly use blown film, from single layer to second layer and third layer. Now, the stretch film is mainly produced by casting method, because the casting line has Uniform thickness and high transparency make it suitable for high-rate pre-stretching. Since single-layer casting does not achieve single-sided adhesion, the application field is limited. The single and double-layer casting has no three-layer casting in the material selection, and the formulation cost is also high, so it is ideal to have a three-layer co-extruded structure. High-quality stretch film manufacturers should have high transparency, high longitudinal elongation, high yield point, high transverse tear strength and good puncture performance.
So what is the most common production process for stretch film manufacturers? as follows:
Lower film unwinding
The lower membrane is mounted on the discharge reel, and the clip on the chain clamps the side of the lower membrane, and the operation of the chain drives the lower membrane to move forward. In order to ensure the stability of the lower membrane tension during operation, the unwinding is installed at the unwinding position. Tension adjustment device.
Upper film unwinding
The upper film is mounted on the discharge reel, and is heat-sealed with the lower film at the heat sealing plate through the tension roller, the cursor tracking device and the guiding roller, and the smoothness of the tension of the upper film is ensured during the running process at the unwinding position. A tension adjustment device is installed.
Divide
The entire film with the product needs to be slit in both the transverse and longitudinal directions to cut the packaged product into individual products.
Stretch forming
When the semi-finished stretched film is run under the stretched forming plate, the lower film is preheated by a hot plate, and then stretched and formed.
