Blow molding film processing wholesale generally follows this process:

Hopper feeding of one material → Plasticizing extrusion → Blowing and stretching → Air ring cooling → V-roller → 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 of 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 main focus is on controlling the following process parameters:

Extruder temperature

During blow molding of LDPE film, the extrusion temperature is generally maintained between 160℃ and 170℃, with the requirement that the die head temperature must be uniform. Excessive extrusion temperature can cause resin decomposition and make the film brittle, particularly leading to a significant decrease in longitudinal tensile strength; conversely, if the temperature is too low, the resin plasticization is poor, 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-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 film bubble after inflation to the diameter of the un-inflated 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 appropriately matched 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 pellets may emit a small amount of organic waste gas due to high temperatures, primarily composed of non-total hydrocarbons.