Blow molding film processing wholesale typically follows this general process:
Hopper feeding one material - plasticizing extrusion → blowing and stretching → air ring cooling → V-shaped plate → traction roller traction → corona treatment → film winding
However, it is worth noting that the performance of blown film processing wholesale films is greatly related to the production process parameters. Therefore, during the blowing process, it is necessary to strengthen the control of process parameters, standardize operational procedures, ensure smooth production, and obtain high-quality film products. In the production process of polyethylene blown film processing wholesale films, the main controls for the following process parameters should be done:
Extruder temperature
When extruding low-density polyethylene (LDPE) film in blow molding, the extrusion temperature is typically maintained between 160℃ and 170℃, and it is crucial to ensure uniform die head temperature. Excessive temperature can lead to resin decomposition and脆ness in the film, particularly a significant decrease in longitudinal tensile strength. On the other hand, too low a temperature results in poor resin plasticization, preventing smooth expansion and stretching, resulting in lower tensile strength of the film, poor surface luster and transparency, and even the appearance of wood grain patterns and unmelted crystalline 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 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.
Wholesale blow molding products generate pollutants.
During the blow molding and wholesale processing, plastic pellets generate a small amount of organic waste gas due to high temperatures, primarily composed of non-total hydrocarbons.
