Mold cavity, also known as concave mold, is the working part of forming plastic parts, according to its structure can be divided into two types: integral and composite.
1. The integral
This type of cavity is processed by a whole metal material, as shown in the right image.The features are simple structure, strong strength, good rigidity, not easy to deform, and the plastic parts have no seam marks, which are suitable for small and medium sized plastic parts with simple shapes.
2. The combined
When the shape of plastic parts is more complicated, the combination cavity is used to improve the processing technology, reduce heat treatment deformation and save quality steel.There are many structural forms of the combined type cavity, as shown in fig.b and c, which are respectively processed by the bottom and the side wall with screws or inlays;FIG. C is consistent with the mold parting direction, which is good for stripping.FIG. D is a local Mosaic, which is convenient to be replaced after easy processing.
Can be used for large complex mold, the sidewalls of the figure e set structure of embedded, four side wall and bottom, respectively, after processing, heat treatment, grinding, polishing pressure into the mold, the walls in the form of lock connection, to make the inside seams tightly, the lateral connection place should be 0.3 ~ 0.4 mm clearance, embedded in the corners of a radius R should be greater than die set of radius R.For whole embedded figure, f, g, is often used in multiple modes or complicated shape of the plastic parts, such as plastic gears, whole set piece of common cold extrusion, electroforming or mechanical machining methods, then embedded, it not only convenient for processing, and high quality steel can be saved.