The basic structure and related concepts of plastic molds
1. What is a plastic mold?
To meet the needs of production and life, people produce production tools according to certain requirements. The mold is the production tool and can generally be reused. Common in the industry are plastic molds, metal stamping molds, die casting molds, blow molding molds, extrusion molds, etc. Broadly speaking, some daily life knife molds, paper molds, plaster molds, and even wood molds for moon cakes are all Can be called a mold. Plastic molds are essential molds for injection molding production.
Plastic mold structure and classification
Second, the basic structure of the mold and related concepts
1. Mold base is mold base: MoldBase. The mold base is the skeleton of the entire mold. All
Mold Parts must be made with the mold base in mind. The cost of the mold base generally accounts for about 30% of the entire mold. The mold base is manufactured by a special large mold base factory and has been standardized. Each mold manufacturer only needs to customize it to the mold base factory according to its own needs. The mold base is divided into panel, A plate (front template), B plate (rear template), C plate (square iron), bottom plate, thimble panel, thimble bottom plate, cylinder, guide post, return needle, thimble, support head, limit Bit nails and so on. At present, the large-scale mold embryo manufacturers in the Pearl River Delta region include Longji mold embryos (LKM), Hongfeng mold embryos, and China mold embryos. Among them, LKM is the most famous. Its mold molds are widely used by mold manufacturers. Are guaranteed.
2. The
Mold Core is also called the cavity, that is, the molding core embedded in the mold base template. Divided into front mold kernel, rear mold kernel, commonly known as front mold (Cavity), rear mold (Core). Why embed the mold kernel in the template? Mainly to save costs. Because plastic has very high requirements on the steel characteristics of the mold, such as hardness, corrosion resistance, high temperature resistance (thermal deformation), etc .; and the template of the mold blank does not need too high requirements. The hardness of the mold core is generally 45 ~ 65HRC, and the template hardness of the mold base is 30 ~ 45HRC; the steel material used for the mold core can reach RMB200 per kilogram, while the steel material of the mold base generally only needs RMB20 ~ 30 yuan.
Note: HRC is Rockwell hardness.
3. Chirp: Sprue. The injection nozzle of the barrel of the injection molding machine injects the molten plastic material into the cavity through the device.
4. The slider is also called line position: Slider. Structural parts that must be used for smooth mold release. Because of the special structure of some products, if there are free sides, there are reverse buckles (hooks), etc., you need to use the row to release the mold.
5. Oblique top: Angle-Lifter. Similar to the row position, it is also a structural component that must be used for smooth mold release.
6. There are some terms related to the mold: parting line (P / L), mold reference, shrinkage (Shrinkage), layout (Layout), steel material, copper male (electrode, its material is copper, graphite, etc ), Reverse buckle, water transportation, draft angle (Draftangle), cold feed well, runner, injection simulation, mold split, mold exit, opening & closing steps, mold number, polishing (saving mold), soft mold, Hard mold, mold surface treatment, trial mold (TESTMOLD), mold modification, mold loading, cross-molding, etc.
May 26, 2020
