Blow molding film processing wholesale process generally follows this workflow:

Hopper feeding one 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 of process parameters, standardize process operations, and ensure the smooth progress of production, as well as obtaining high-quality film products. In the production of polyethylene blow molding bulk film, the main tasks in controlling the process parameters include:

Extruder temperature

During blow molding and wholesale of LDPE (Low Density Polyethylene) film, the extrusion temperature is typically maintained between 160℃ and 170℃, and it is crucial to ensure uniform die head temperature. Excessive extrusion temperature can cause resin decomposition, making the film brittle, particularly reducing the longitudinal tensile strength significantly; whereas, too low temperature leads to poor resin plasticization, preventing smooth expansion and stretching, resulting in lower film tensile strength and poor surface luster and transparency. Moreover, it may exhibit wood grain-like 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, 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 generate pollutants.

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