Blow molding film processing wholesale process generally includes:

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 blown film processing in bulk has a significant relationship with the production process parameters. Therefore, during the blowing film process, it is essential to strengthen control over the process parameters, standardize process operations, ensure smooth production, and obtain high-quality film products. In the production of polyethylene blown film processing in bulk, the control of the following process parameters is primarily 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脆化的film, particularly a significant decrease in longitudinal tensile strength; whereas, too low a temperature results in poor resin plasticization, preventing smooth expansion and stretching. The film's tensile strength is lower, and its surface luster and transparency are poor, with potential 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, and 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, the blow-up ratio should be appropriately matched 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.

Wholesale blow molding products produce pollutants.

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