Toolbox

Blow molding film processing wholesale process is generally as follows:

Hopper feeding of 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 film blowing 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 main tasks for controlling the process parameters include:

Extruder temperature

When blow molding LDPE film, the extrusion temperature is generally controlled between 160℃ and 170℃, and it is essential to ensure uniform die temperature. Excessive extrusion temperature can lead to resin decomposition, making the film脆，especially significantly reducing the longitudinal tensile strength; if too low, the resin does not塑化 properly, cannot be smoothly expanded and stretched, resulting in lower film tensile strength and poor surface gloss and transparency. In extreme cases, it can even exhibit wood grain-like patterns and unmelted crystal nuclei (fish eyes).

2. Blowing Ratio

Blow-up ratio is one of the key controls in the production process of blown film for wholesale plastic processing, referring to the ratio between the diameter of the bubble after blowing and the diameter of the unblown tube ring. The blow-up ratio represents the lateral expansion multiple of the film and, in essence, involves stretching the film laterally, which exerts a certain degree of orientation on the plastic molecules. An increased blow-up ratio enhances the film's lateral strength. However, the blow-up ratio should not be too high, as it can lead to unstable bubbles and more frequent wrinkling in the film. Therefore, it 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 and wholesale processing, plastic granules emit a small amount of organic waste gas due to high temperatures, with the main component being non-total hydrocarbons.