1. The cavity and core are three-dimensional.
The cavity and the core directly form the inner and outer shapes of the plastic part. These complex three-dimensional surfaces, especially the blind holes in the cavity, are very difficult to process. Traditional processing methods have a high level of skill for workers, and require many auxiliary tools and long processing time.
2. There are high requirements for accuracy and surface quality, and a long service life is also required.
At present, the dimensional accuracy requirements of general plastic parts are it6-7, and the surface roughness is ra0.2-0.1μM. The dimensional accuracy requirements of the corresponding injection mold parts are it5-6, and the surface roughness is less than ra0.1μM. The surface of the laser disk The roughness should reach the level of 0.02-0.01μM. Mirror processing is used, and the mold surface roughness is required to be less than 0.01μM. In order to improve efficiency and reduce costs, injection molds with a long service life are required. At present, the injection mold needs to have a service life of more than 1 million times. In order to prevent the injection mold from deforming under pressure, a rigid mold base should be used, the mold thickness should be increased, and support columns or tapered positioning elements should be added.
An important factor affecting product deformation and dimensional accuracy is the ejector device. The ejector point must be selected to ensure uniform demolding. Most of the high-precision injection molds use inlaid or fully assembled structures, which requires the processing accuracy and interchangeability of mold parts to be greatly improved.
3. The processing technology is long and the manufacturing time is tight.
Mold expert Luo Baihui believes that for injection molded parts, most of them form complete products with other parts. In many cases, they wait for injection molded parts to be launched after other parts are completed. The shape or size accuracy of the product is relatively high, and the characteristics of the resin material are different. After the mold is manufactured, the mold needs to be repeatedly tested and modified, so the development and delivery time of the mold is very tight.
4. Design and manufacture in different places.
Mold manufacturing is not the ultimate goal, but the final product design proposed by the user. Mold manufacturers design and manufacture molds according to user requirements. In most cases, products produced by injection molding are also produced by other manufacturers.