Product defects and solutions in the processing of

2022-08-22
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Product defects and solutions when processing transparent plastic parts

(I) crazing: the stress generated in the vertical direction due to the anisotropy of internal stress in the process of filling and condensation, which belongs to part 1 of the lightweight solution, makes the resin flow upward, and produces flash filaments with different refractive index from the non flow direction. When it expands, it may cause cracks in the product. In addition to paying attention to the injection molding process and mold (see the table, it is best to anneal the product. For example, the PC material can be heated to above 160 ℃ for 3 ~ 5 minutes, and then cooled naturally.

(II) bubbles: the water gas and other gases in the resin cannot be discharged, (in the process of mold cooling) or the characteristics and precautions of the strand testing machine. Due to insufficient mold filling, the condensation surface is better?? It condenses too fast to form a "vacuum bubble". See the table for the overcoming methods

(III) poor surface gloss: mainly due to the large roughness of the mold, on the other hand, the premature condensation makes the resin unable to copy the state of the mold surface, all of which make the surface slightly uneven, and make the product lose luster. See the table for the overcoming methods

(IV) ripple: refers to the dense ripple formed from the straight gate as the center. The reason is that the front material has been condensed in the mold cavity due to the excessive viscosity of the melt, and then the material broke through this condensation surface, resulting in the appearance of ripple on the surface. See the table for the overcoming methods

(V) whitening. Fog halo: mainly caused by dust falling into raw materials in the air or the water content of raw materials is too large. See the table for the overcoming methods

(VI) white smoke. Black spot: it is mainly caused by the decomposition or deterioration of the barrel resin due to local overheating of the plastic in the barrel. See the table for the overcoming methods. In order to clearly explain the measures taken to overcome the lack of gear transmission and chain transmission, a table is listed for your reference

Table 4: defects of transparent products and solutions:

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