There are many kinds of results caused by degradation, and the degree and severity of the problem vary. Degradation is caused by the destruction of the raw materials, and the long-chain molecules forming the plastic will be resolved under the action of excessive heat or excessive shear stress. The volatile gas generated during the molecular analysis process can accelerate the degradation process, which will cause the decolorization of the raw materials. In severe cases, the plastic injection mold may be completely decolorized and its mechanical properties may be poor. The local degradation will only cause dark streaks or spots. Piece.
Under normal circumstances, the shape of the Instrument panel mould should match the shape of the mould. The deformation problem refers to the product deformity. When the situation is serious, the product will be completely deformed when it is ejected from the plastic injection mold. When the situation is not serious, the product shape will appear small irregularities. Longer, unsupported edges and larger surfaces on the product are areas that are more susceptible to deformation.
The impurity is caused by impurities mixed into the raw materials, for example, the raw materials are mixed into the feed hopper. The manifestation is the appearance of patches or markings of different colors on the product, and a common situation is the appearance of black patches. Impurities in plastic injection molds may be very small plaques, and in severe cases, they may also appear as obvious streaks or large fading.
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 and other parts of the raw materials are different in texture and nature, forming a skin that can be peeled off. When the delamination is severe, the entire cross-section is composed of multiple layers, which are not fused together. When it is lighter, the appearance of the product may meet the requirements, but the mechanical properties of the product will be damaged.
The surface finish of the product should be the same as the finish of the plastic injection mold. When the finishes of the two are different, gloss/shadow will occur. When the problem occurs, the surface that should be smooth will appear dim, and the surface that should be rough will appear shiny.
Vacuum bubbles appear in the form of bubbles, which are easy to see on transparent products and can also be seen on cross-sections of opaque products. Bubbles are the vacuum part of the product. Insufficient pressure in the cavity of rear bumper mould, insufficient time for pressurizing the cavity, and too small runner and gate sizes will all cause bubbles.