What are some common problems about automobile injection mold molding
Apr 13, 2022
Classification of common problems in automobile injection mold molding:
1. Degradation
There are many kinds of results that consist of degradation, and the extent and severity of the problem vary. Degradation is caused by damage to the material, and the long-chain molecules that make up the plastic will decompose under the action of excessive heat or excessive shear stress. The volatile gas generated in the molecular analysis process can speed up the degradation process, which will cause the material to decolorize. In severe cases, it may cause the plastic injection mold to completely decolorize and cause its mechanical properties to be poor, while local degradation will only cause dark streaks or spots. yuan.
2. Deformation
Under normal conditions, the shape of the plastic injection mold should match the shape of the mold. The deformation problem refers to the deformity of the product. When the situation is severe, the product will be completely deformed when it is ejected from the plastic injection mold. When the situation is not severe, the shape of the product will show small irregularities. Long, unsupported edges and large flat surfaces on the product are areas that are more prone to deformation.
3. Impurities
The reason for the occurrence of impurities is that there are impurities mixed into the material, for example, the material is mixed with impurities in the feed funnel. It manifests as patches or markings of different colors on the product, usually black patches. Contaminants in plastic injection molds may be very small patches, and in severe cases they can manifest as noticeable streaks or large patches of discoloration.
4. Layering
The layering defects of plastic injection molds will form a "skin effect" on the surface of the product, that is, the surface of the product is different in texture and properties from other parts of the material, forming a layer of epidermis that can fall off. When the delamination is severe, the entire cross-section is composed of multiple layers that are not fused together, and when the delamination is lighter, the appearance of the product may meet the requirements, but the mechanical properties of the product will be damaged.
5. Gloss/Shadow
The finish of the product surface should be the same as the finish of the plastic injection mold, when the finish of the two is not the same, gloss/shadow occurs. Problems occur when surfaces that should be smooth appear dull and surfaces that should be rough appear glossy.
6. Bubbles
The vacuum bubbles are presented in the form of bubbles, which are easy to see on transparent products, and can also be seen on the cross-section of opaque products. Bubble is the vacuum part of the product. The lack of cavity pressure in plastic injection molds, the lack of cavity pressurization time, and the small size of the runner and gate will all lead to the occurrence of bubbles.
