Blow molding film processing wholesale process generally includes the following steps:

Hopper feeding → 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 bulk film is greatly related to the production process parameters. Therefore, during the film blowing process, it is essential to strengthen control over process parameters, standardize operational procedures, and ensure smooth production to obtain high-quality film products. In the production of polyethylene blow molding bulk film, the main focus is on controlling the following process parameters:

Extruder temperature

During the blow molding process of low-density polyethylene (LDPE) film, the extrusion temperature is typically maintained between 160℃ and 170℃, with the requirement that the head temperature be uniform. Excessive extrusion temperature can cause the resin to decompose, making the film brittle and significantly reducing its longitudinal tensile strength. On the other hand, if the temperature is too low, the resin will not be properly plasticized, preventing smooth expansion and stretching. The film will have lower tensile strength, poor surface 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 wrinkles in the film. Therefore, the blow-up ratio should be properly coordinated 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 produce pollutants.

During the blow molding processing and wholesale manufacturing process, plastic granules volatilize at high temperatures, producing a small amount of organic waste gas, primarily consisting of non-total hydrocarbons.