Seven Systems of Plastic Mold, with Modular Design

The plastic mold structure is divided into seven systems according to function, which is: pouring system, temperature control system, molding parts system, organization system, guiding and positioning system, ejection system, exhaust system, etc.

The Plastic Mold Structure:

1. Pouring system: The gating system refers to the part of the runner before the plastic enters the cavity from the nozzle, including the main runner, the cold slug well, the runner, the gate, and the pulling needle.
2. Temperature control system: The temperature adjustment system is to meet the requirements of the injection process for the mold temperature, and a temperature adjustment system is required to schedule the mold temperature. Regarding injection molds for thermoplastics, the main thing is to design a cooling system to cool the mold (it can also be heated). The common method of mold cooling is to open a cooling water channel in the mold and use the circulating cooling water to take away the heat of the mold. In addition to using cooling water to pass hot water or hot oil, the heating of the mold can also install electric heating elements in and around the mold.
3. Forming part system: The forming part system refers to the combination of various parts that constitute the shape of the product, including movable mold cores, movable mold inserts, fixed mold cores, fixed mold inserts, etc. Under normal conditions of fixed mold, the outer surface of molded products, and under normal conditions of movable mold, the inner and outer surfaces of molded products. The fixed and movable mold cores are combined to form a cavity, and then the post-injection system will flow the plastic into the cavity. After cooling, the fixed and movable mold cores are opened, which is the required product.
4. Organization system: The organization system refers to the fact that the inversion of the product is inconsistent with the normal demolding direction, and it is necessary to do organization core pulling to meet the normal demoulding of the product. The normal tissue on the mold is divided into two types, one external lateral core pulling (such as outer slider), and the other internal lateral core pulling (such as inclined top, inner slider).
5. Guide positioning system: The guide system refers to various sliding systems on the mold, such as the zero-degree positioning block on the mold base; the return needle and EGP guide post on the ejector plate; and the template on the mold.
6. Ejector system: The ejector system means that the product needs to be ejected from the movable mold core, so the ejector system is required. The ejector pin system includes ejector pin ejection, push block ejection, push plate ejection, hydraulic cylinder ejection, Air pressure ejection, etc.
7. Exhaust system: The exhaust system refers to the fact that during the injection molding process, the melt will replace the gas in the cavity. If the gas is not discharged in time, it will cause difficulty in filling the melt and cause insufficient injection to fill the cavity. , it will cause regional scorching of the product or the bonding line is obvious, and the area where the product is bonded is not easy to fill. There are many types of exhaust. The conventional method is to make exhaust grooves on the parting surface of the female mold core, and also to make exhaust grooves on the parting side, exhaust sheets on the male mold side, insert exhaust, and insert needle exhaust. , Thimble exhaust, exhaust steel exhaust, etc.

​

Reference: daytime