Blow molding film processing wholesale process is generally as follows:

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

However, it is worth noting that the performance of blow molding processed bulk film is greatly related to the production process parameters. Therefore, during the blowing film process, it is essential to strengthen the control over process parameters, standardize process operations, and ensure smooth production and the production of high-quality film products. In the production process of polyethylene blow molding bulk film, the main controls over the following process parameters should be implemented:

Extruder temperature

During blow molding of low-density polyethylene (LDPE) film, the extrusion temperature is typically maintained between 160℃ and 170℃, with the requirement for uniform die head temperature. Excessive extrusion temperature can lead to resin decomposition and脆 film, particularly causing a significant drop in longitudinal tensile strength; whereas, too low a temperature results in poor resin plasticization, preventing smooth expansion and stretching, resulting in lower film tensile strength, poor surface luster and transparency, and even the appearance of wood grain patterns and unmelted crystal nuclei (fish eyes).

2. Blowing Ratio

Blow-up ratio is one of the key control points in the blowing film production process for wholesale film manufacturing, referring to the ratio between the diameter of the blown film 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 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 may cause instability in the film bubble and lead to wrinkles 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 processing and wholesale manufacturing, plastic granules volatilize at high temperatures, producing a small amount of organic waste gas, primarily consisting of non-total hydrocarbons.