Blow molding film processing wholesale process generally includes:

Hopper feeding one material → plasticizing extrusion → blowing and stretching → air ring cooling → V-shaped clamp → 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 process, it is essential to strengthen the control of process parameters, standardize operational procedures, ensure the smooth progress of production, and obtain high-quality film products. In the production of polyethylene blow molding processed wholesale film, the main focus is on controlling the following process parameters:

Extruder temperature

During blow molding and wholesale of low-density polyethylene (LDPE) film, the extrusion temperature is typically controlled between 160℃ and 170℃, and it is essential to ensure uniform die head temperature. Excessive extrusion temperature can cause resin decomposition, making the film brittle and significantly reducing the longitudinal tensile strength. On the other hand, if the temperature is too low, resin plasticization is poor, preventing smooth expansion and stretching. The film will have lower tensile strength, poor surface gloss and transparency, and may even exhibit patterns resembling wood grain as well as 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 between the diameter of the blown bubble and the diameter of the unblown tube ring. The blow-up ratio represents the lateral expansion multiple of the film, which is essentially a lateral stretch of the film. This stretch exerts a certain degree of orientation on the plastic molecules, and as the blow-up ratio increases, it enhances the film's lateral strength. However, the blow-up ratio should not be too high, as it can cause instability in the bubble and lead to wrinkles in the film. 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' generated pollutants

During the blow molding wholesale processing, plastic granules produce a small amount of organic waste gas due to high temperatures, with the main component being non-total hydrocarbons.