The key to automobile plastic mold processing: 1. In te […]
The key to automobile plastic mold processing:
1. In terms of molds, micro-injection molding requires much higher processing equipment than traditional injection molding:
Micro-injection molding generally has two trends in mold processing: the first is to select mirror spark machining. In order to ensure high precision, it is best to use graphite electrodes for EDM, because the loss of graphite electrodes is higher than that of ordinary copper electrodes. Much smaller. The second comparison commonly used processing method is to select electroforming molds. The electroforming technology can ensure very high accuracy, but the defect is that the processing cycle is long, each cavity must be processed independently, and if there is minor damage in production, it cannot be corrected. , Can only replace the damaged acupoint from scratch.
2. In terms of mold, mold temperature is also a very important parameter for micro-injection. For customers facing high-end needs, the current common practice is to borrow the concept of high-gloss injection molding and introduce a rapid heating and cooling system:
Theoretically, high mold temperature is very helpful for micro-injection. For example, it can avoid difficult filling and lack of material for thin walls. However, too high mold temperature will bring new questions, such as lengthening the cycle and shortening the deformation after mold opening. Therefore, it is important to introduce a new mold temperature control system. The mold temperature can be improved during the injection molding process (beyond the melting point of the plastic used), so that the melt can quickly fill the cavity and avoid the melt temperature drop during the filling process Too fast and form incomplete filling; and when demolding, the mold temperature can drop quickly, keep it at a temperature slightly lower than the plastic thermal deformation temperature, and then open the mold to eject.
In addition, automotive plastic mold processing because micro-injection molding is a product with a quality of milligrams. If the general casting system is used to inject the product, even after optimization and improvement, the quality of the product and the material in the casting system It is still 1:10. As long as less than 10% of the material is injection molded into micro-products, a lot of casting system condensate occurs, so micro-injection probably uses warm runner casting system.