There are two types of plastic injection mould: static and dynamic.
In the injection molding machine side of the injection head with gate sleeve for the static mould, the static mould is generally composed of gate sleeve, plate, template, simple mould (especially the static mould without core mould) can also do not use the plate, directly with a thicker template can be. The gate sleeve is generally a standard part and is not recommended to be cancelled unless for special reasons. The use of the gate sleeve is conducive to the installation of the mould, easy for replacement, no need to polish themselves. Some special mould sprue sleeves can be drilled out or cut with taper lines. Part of the mould must be static mould release, also must add the static mould release mechanism. The structure of moving die is generally moving template, moving die by the plate, demoulding mechanism and die foot and installed fixed plate.
Stripping mechanism in addition to the stripper rod, there is a return rod, part of the mould should be added spring to achieve such as automatic stripping and other functions. There are guide posts, cooling water holes, flow channels and other basic structure of the mold is indispensable. Of course, the inclined guide mould and the inclined guide box, the inclined guide column, etc. When designing a mould for a product, the first thing to do is to set the basic structure size of the mould to prepare the material, so as to accelerate the speed of molud manufacturing. Complex products should first draw the product drawing, and then set the size of the mould. Now the mould is basically to heat treatment, increase the hardness of the mould, improve the service life of the mould. Before heat treatment, the first preliminary processing of the template: drilling well guide column hole, return hole (moving mould), cavity hole, screw hole, gate set hole (moving mould) cooling water hole, milling good flow channel, cavity, some moulds should also be milling good inclined guide box. Now the common precision mould template is generally used CR12, CR12MOV and some professional die steel, cr12 hardness can not be too high, often cracking in HRC60 degrees, the commonly used hardness of the template is generally HRC55 degrees. Core hardness can be above HRC58. If the material is 3Cr2w8v, the surface hardness should be treated by nitriding after manufacturing. The hardness should be HRC58 or above, and the nitriding layer should be as thick as possible.
Gate is directly related to the beauty of plastic parts, gate design is not good, easy to produce defects. It is easy to create snake flow in the absence of any obstruction. For demanding products, overflow and exhaust should also be designed. Overflow can be used to push rod, do not have overflow on the template, so as not to affect the life of the mould.