Blow molding film processing wholesale process is generally as follows:

Hopper feeding one material → plasticizing extrusion → blowing and stretching → air ring cooling → V-groove → 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 process, it is essential to strengthen the control over process parameters, standardize process operations, and ensure the smooth progress of production to 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 processing of low-density polyethylene (LDPE) film, the extrusion temperature is typically maintained between 160℃ and 170℃, with the requirement that the die head temperature be uniform. Excessive extrusion temperature can cause the resin to decompose, making the film brittle, especially leading to a significant decrease in longitudinal tensile strength; conversely, 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, reduced 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 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 stretch that exerts a certain degree of orientation on the plastic molecules. 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 cause wrinkles in the film. Therefore, it should be properly coordinated 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 produce pollutants.

During the blow molding and wholesale processing, plastic pellets volatilize at high temperatures, producing a small amount of organic waste gas.