What is the blow molding process

What is the blow molding process In simple terms, the blow molding process is a method of producing a plastic hollow product by using gas pressure to inflate a molten plastic parison in a closed mold. Classification of blow molding process: extrusion blow molding, injection blow molding, stretch blow molding Extrusion blow molding is the extrusion of the parison from the die into the interior of the mold to complete the molding process.

Injection blow molding is to inject the parison into the mold to complete the molding process. Stretch blow molding is to first form a parison by extrusion or injection molding. After the parison reaches a suitable stretching temperature, it is longitudinally stretched by internal or external mechanical force, and gas is introduced into the interior while stretching. , to complete the production of plastic products. Here, we take the extrusion blow molding process as an example.

During the blow molding process, the granular plastic raw materials are automatically added to the barrel by the blow molding machine. After high temperature heating and stirring and mixing by the screw, the raw material rubber pellets are formed into molten plastic preforms. The parison is extruded into the mold through the die head, at the same time, the mold is closed, the fixture is clamped, and the blowing hole at the bottom of the blow molding machine blows gas into the parison, so that the parison expands and adheres to the inner wall of the mold, and the product is completed and enters the cooling stage. . The mold is opened, the product is demolded, and the production is completed.

What raw materials are used in the blow molding process? Almost all thermoplastic materials can be used as raw materials for blow molding, such as high density polyethylene (HDPE), polypropylene (PP), etc. These two are recommended for everyone to use, whether it is material properties or other, they are ideal choices. Of course, there are other raw material options available for the blow molding process. Advantages of blow molding process 1. Fast molding process, stable product quality 2. Closed production process, no pollution 3. Low energy consumption in the process, energy saving 4. Small equipment footprint 5. Wide production range, multi-purpose machine What products can be produced by the blow molding process?

The blow molding process can produce not only small-capacity plastic bottles of a few milliliters, but also large-capacity plastic buckets and water storage tanks of thousands of liters. In addition to containers, the blow molding process can also produce floats, barricades, pallets, ton barrels, double ring barrels and kayaks, among others.

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