1. The production cycle is longer than injection molding and injection molding, and the production efficiency is low, especially for thick-walled parts.
2. There are often thick flash edges on the parts, and the thickness of each die edge is different, so it will affect the accuracy of the height dimension of the workpiece. Thus, the post-processing workload is large, and the cost of the plastic parts is correspondingly increased.
3. Thick-walled parts and parts with deep holes and complicated shapes are difficult to mold. If the mold has elongated molding rods and the parts have thin inserts, they are easy to bend and deform during molding, so these parts are not suitable.
4. Compared with injection molding, the technical requirements are high, and the labor intensity is relatively large, especially the mobile pressing mold. Since the mold is heated, the raw materials often have dust fibers flying and the working conditions are poor.
5. The pressing mold is subject to the combined action of high temperature and high pressure. Therefore, the mold material is required to be high, and important parts should be heat treated. At the same time, the impact mold is subjected to large impact vibration, easy to wear and deform, and has a short service life. Generally only 200,000 to 300,000 times.