Blow molding film processing wholesale process generally includes:

Hopper feeding one material → plasticizing extrusion → blowing and stretching → wind ring cooling → V-shaped clamp → roller traction → corona treatment → film winding

However, it is worth noting that the performance of blown film for plastic processing wholesale is greatly related to the production process parameters. Therefore, during the blowing process, it is essential to strengthen control over process parameters, standardize operational procedures, and ensure smooth production while obtaining high-quality film products. In the process of producing polyethylene blown film for wholesale, the following process parameters should be well-controlled:

Extruder temperature

During blow molding processing of low-density polyethylene (LDPE) film, the extrusion temperature is generally maintained between 160℃ and 170℃, and it is crucial to ensure uniform die head temperature. Excessive extrusion temperature can lead to resin decomposition and脆化 of the film, particularly causing a significant drop in longitudinal tensile strength; on the other hand, if the temperature is too low, the resin will not be properly plasticized, preventing smooth expansion and stretching, resulting in lower tensile strength of the film. Additionally, the film's surface will have poor luster and transparency, and may even exhibit wood grain-like patterns and unmelted crystal nuclei (fish eyes).

2. Blowing Ratio

Blow-up ratio is one of the key control points in the production process of blown film for bulk processing, referring to the ratio of the diameter of the film bubble after inflation to the diameter of the un-inflated tube ring. The blow-up ratio represents the lateral expansion multiple of the film, which is essentially a lateral stretching of the film. This stretching exerts a certain degree of orientation on the plastic molecules, and as the blow-up ratio increases, it enhances the lateral strength of the film. However, the blow-up ratio should not be too high, as it can lead to instability in the film bubble and the film may wrinkle easily. Therefore, the blow-up ratio should be appropriately matched with the draw ratio. Generally speaking, the blow-up ratio for low-density polyethylene (LDPE) film should be controlled between 2.5 and 3.0.

Blow molding wholesale products generate pollutants.

During the blow molding processing and wholesale manufacturing process, plastic pellets emit a small amount of organic waste gas due to high temperatures, primarily consisting of non-total hydrocarbons.