Blow molding film processing wholesale process generally includes:

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

However, it is worth noting that the performance of blow molding processed wholesale film is greatly related to the production process parameters. Therefore, during the blowing film process, it is essential to strengthen the control of process parameters, standardize process operations, ensure the smooth progress of production, and obtain high-quality film products. In the production of polyethylene blow molding processed wholesale film, the control of the following process parameters is mainly focused on:

Extruder temperature

During blow molding of LDPE film, the extrusion temperature is typically maintained between 160℃ and 170℃, and it is crucial to ensure uniform die head temperature. Excessive temperature can cause resin decomposition, making the film brittle and significantly reducing its longitudinal tensile strength; conversely, if the temperature is too low, the resin will not plasticize properly, preventing smooth expansion and stretching, resulting in lower tensile strength of the film. Additionally, the surface will have poor luster and transparency, and may even exhibit wood grain 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 blow molding wholesale, referring to the ratio of the diameter of the blown film bubble to the diameter of the unblown 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, with an increased blow-up ratio enhancing the film's lateral strength. However, the blow-up ratio should not be too high, as it can lead to instability in the film bubble and cause the film to wrinkle easily. Therefore, the blow-up ratio should be appropriately matched with the draw ratio. Generally, 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 processing, plastic granules produce a small amount of organic waste gas due to high temperatures, with the main component being non-total hydrocarbons.