Design principles for wall thickness of plastic products
The principles of wall thickness design for plastic parts are as follows:
1. Making the wall thickness even is the first principle of plastic part design, it can make filling, cooling and shrinking even, good molding, high dimensional accuracy and high productivity. If the wall thickness can not be even due to some special requirements of plastic parts, the inclined plane should be used to gradually transition between the thick and thin walls. In addition, the ratio of thickness must be strictly controlled as follows: thermosetting plastic: pressing 1:3, extruding 1:5 thermoplastic: injection molding 1: (1.5~2);
2. Under the conditions of meeting the requirements of the structure and use of the plastic parts, use a smaller wall thickness as much as possible, so that we can get: the mold cools quickly, the part weight is light and saving material:
3. The design of the wall thickness of the plastic part should be able to withstand the impact and vibration of the mold ejection device, etc.;
4. There must be sufficient thickness at the connection and fastening place of the plastic part, the place where the insert is buried, and the junction of the plastic melt at the hole (welding mark);
5. When determining the wall thickness, the required strength during storage and handling must be considered;
6. To meet the wall thickness required for melt filling during molding, it is necessary to avoid insufficient filling or thin walls that are easy to burn, but also to avoid melt fracture or thick walls that are easy to produce depressions;
7. Different plastics have different reasonable wall thicknesses due to their different fluidity, see list 1 for details;
8. The fire rating required by the product, different fireproof grades correspond to different product wall thicknesses, if the product wall thickness has been determined, in order to achieve the required fireproof grade, it is often necessary to replace higher grade materials, if there is no suitable material, then it needs to be increased product wall thickness.
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