Blow molding film processing wholesale process is generally as follows:

Hopper feeding one material → Plasticizing extrusion → Blowing and stretching → Air ring cooling → V-plate → 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 film 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 control of the following process parameters is mainly focused on:

Extruder temperature

During blow molding of low-density polyethylene (LDPE) 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 lead to resin decomposition and脆化 of the 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 production process of blown film for blow molding wholesale, referring to the ratio of the diameter of the blown 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 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 film's lateral strength. However, the blow-up ratio should not be too high, as it may cause instability in the bubble and lead to wrinkles in the film. Therefore, it should be coordinated with the draw ratio appropriately. 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' generated pollutants

During the blow molding processing and wholesale processing, plastic pellets generate a small amount of organic waste gas due to high temperatures, primarily consisting of non-total hydrocarbons.