What is the difference between injection mold and blow mold?

Author: MULAN - Plastic Molding Manufacturer

The two processing technologies of mold products, injection molding and blow molding, have their own characteristics. Simply put, the blow molding mold adopts the "injection + blowing" method, and the injection mold adopts the "injection + pressure" method. Injection molding is a solid core, blowing The plastic molding is hollow, the injection mold has a gate cross section, and the blow molding mold surface and air outlet are uneven. 1. Injection mold Injection molding is the injection molding process of materials, that is, to melt the plastic materials, and then inject them into the mold cavity. After the plastic enters the mold, it is cooled, and then processed into the required shape. The formed shape is the final appearance of the finished product. Additional processing is required. In addition, the injection molding process allows fine control over details, during which protrusions, ribs, threads and other parts can be molded in one step.

2. Blow molding Blow molding is a relatively fast-growing plastic processing method, also known as hollow blow molding. Its processing principle is: put the thermoplastic resin or tubular plastic blank obtained by injection molding into the mold, and then inject compressed air into the mold after the mold is closed, so that the plastic blank is inflated and close to the inner wall of the mold, and then obtained by cooling and demoulding. Hollow products. It is worth mentioning that, very similar to hollow product blow molding, the manufacturing process of blown film does not use molds in principle, which is completely different from processing injection molding.

According to the blank production method, blow molding can be divided into extrusion blow molding and injection blow molding, and the new development direction is multi-layer blow molding and stretch blow molding. 3. The difference between blow molding and injection mold In fact, the product expression form of injection mold and blow mold is the main difference. The products manufactured by the injection molding process are usually thicker, the manufacturing is relatively simple, and the requirements for raw materials are relatively low.

The blow molding process is different, and the product is thin and transparent. Because of this, there are certain requirements for the toughness and tensile properties of the raw materials, and the processing requirements for the blow mold are relatively high. Injection molds and blow molds are widely used in daily life, and each has its own advantages and characteristics, and the development prospects are good.