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Taizhou Union Plastic Mould Co.,Ltd

ADD:No.26, MaoFeng Street, Beicheng Development Area, Huangyan Dist., Taizhou, Zhejiang, China

Post Code: 312080

Contact:Ms vicky






Don't You Understand The Main Points Of Designing Injection Mold?
Mar 06, 2019

Plastic injection moulds are the most widely used moulds in all plastic moulds, which can form complex and high-precision plastic products. This article is only a cursory introduction.

Since it is a chain structure, the shrinkage direction of plastics during processing is also related to the orientation and cooling shrinkage of polymer molecular chain under the action of stress. The shrinkage in the flow direction is more than that in the vertical direction.

The shrinkage of the product is also related to the shape of the product, gate, hot expansion and cold contraction, temperature, pressure holding time and internal stress. Usually the book provides a wide range of shrinkage rate, in the actual application of the consideration is the product wall thickness, structure and determine the size of injection molding temperature pressure and orientation. If general product does not have core to support, shrink accordingly want some bigger. Plastic injection mold is basically divided into static mold and dynamic mold.

In the injection molding machine injection head side of the gate sleeve for the static mold, the static mold generally has the gate sleeve, against the plate, the template composition, simple mold (especially the static mold without a core mold) can also not use against the plate, directly with a thicker template. Gate bushing is generally standard parts, except for special reasons, it is not recommended to cancel.

The use of the gate cover is conducive to the installation of mold, easy to replace, without their own polishing. Some special mold gate sleeves can be drilled out or cut with taper lines. Part of the mold must be static mold demoulding, but also add static mold demoulding mechanism. The structure of the moving die is generally the moving template, the moving die against the plate, the demoulding mechanism and the foot of the die and the mounting plate.

Gate is directly related to the beauty of plastic parts, gate design is not good, easy to produce defects. It is easy to generate snake flow without any obstruction. For demanding products, overflow and exhaust should also be designed. Overflow place can use jacking rod, do not have overflow flying edge on the template, just won't affect the life of the mold

In addition to the stripper bar, there is a return bar in the stripper mechanism, and some molds also need to add springs to achieve such functions as automatic stripper. There are guide column, cooling water hole, runner and so on is the basic structure of the indispensable mold. Of course, oblique guide mold and oblique guide box, such as oblique guide column.

When designing a mold for a product, the basic structure size of the mold should be set to prepare materials to accelerate the speed of mold manufacturing. For complex products, the product drawing should be drawn first, and then the mold size should be determined. Now the mold basically to heat treatment, increase the hardness of the mold, improve the service life of the mold.

In the heat treatment before the template for preliminary processing: drilling guide column hole, return hole (moving mold), cavity hole, screw hole, gate hole (static mold), pull hole (moving mold), cooling water hole, etc., milling runner, cavity, some molds should also be milling inclined guide box.