The design content of machined plastic components mainly includes four aspects:
1. Clear requirements
Clear requirements mainly refer to making clear the occasions where the components are used, that is, what needs the components need to meet, which is the prerequisite for selecting processing materials and manufacturing processes.
2. Material selection
Material selection is also a very important aspect in structural design. Structural design is the determination of component geometry, which not only meets the functional requirements of components, but also takes into account the performance of materials, manufacturing technology and other requirements.
3. Sizing
The determination of size is related to the later use of plastic components, and it is also one of the related design contents of component strength, stiffness and stability. Because the strength and stiffness of plastic are much smaller than that of metal, plastic components are usually used in occasions with small external load, and the strength problem is not prominent at this time. However, it is worth pointing out that plastic components do not use the method of increasing the size when they need to strengthen the stiffness, because this may cause the decline of molding quality, and the final effect will be counterproductive.
In fact, most mechanical products with advanced performance are not fundamental improvements in their basic principles, but often because they make use of advanced achievements in other related fields. The machine is made of materials, and the material performance is not advanced. The mechanical properties are often limited. We have good materials, but we don't make full use of their good performance, and we won't design machines with advanced performance.
There are many differences between plastics and metals from the physical properties of materials to the molding process. Therefore, if the structural design of plastic parts only starts from the relevant knowledge of the structural design of metal parts, the performance of plastics cannot be brought into play, and the performance of components may not meet the standard, which is likely to cause damage outside the components and even machinery, resulting in adverse consequences.
However, the structural design of plastic parts is also similar to that of metal parts, especially there are many similarities with the structural design of castings. This is mainly because the basic principles of plastic molding processes, such as various molding processes and casting processes, are the same, so the structural design criteria of castings are basically suitable for the structural design of various molded parts.