Blow mold processing concept, blow molding, also known as hollow blow molding, is a rapidly developing plastic processing method. The tubular plastic billet obtained by extrusion or injection molding of thermoplastic resin is heated to a softened state while the plastic embryo is placed in a split mold. Compressed air is passed into the billet immediately after the mold is closed, so that the plastic billet is blown and close to the inner wall of the mold. After cooling and demoulding, all kinds of hollow products are obtained.

The manufacturing process of blow molded film is very similar to that of hollow products in principle, but it does not use molds, which is completely different from the processing of injection molds. From the perspective of plastic processing technology classification, the molding process of blow molded film is usually included in extrusion. However, according to the production method of billet, blow molding can be mainly divided into extrusion blow molding and injection blow molding, and the newly developed multi-layer blow molding and tensile blow molding.

The concept of injection mold processing, that is, thermoplastic injection molding, this method is to melt the plastic material and then inject it into the film cavity. Once the molten plastic enters the mold, it is cooled and shaped into the desired shape according to the mold cavity. The resulting shape is often a finished product and no further processing is required before installation or use as a finished product. Moreover, in injection mold processing, there are many details, such as bumps, ribs, threads, can be molded in a single injection molding operation. The following is the processing and molding diagram of the injection mold of the driving recorder.

The above understanding of the concept between the two, in fact, the main difference between blow mold processing and injection mold processing is the difference in the product, blow molding is the use of gas to form the product, the need for injection molding is generally used to make thicker products. Blow molding is different, because the product is thinner and more transparent, and the slight shortcomings are obvious. Therefore, the requirements are high, and there are some requirements for the toughness and tensile properties of raw materials. The products for processing injection molds are thicker, and the requirements are relatively lower, and the requirements for raw materials are also lower.