In the processing of mold products, what are the reasons for the large surface roughness and lack of gloss?
1. As far as the mold processing equipment is concerned, it is most likely caused by insufficient material supply, resulting in the processed products not meeting the standard.
2. For injection molds or other plastic molds, it may be because the gate is too small or the runner is too thin, such as poor polishing, mechanical abrasion, damp, mist, rust not cleaned, etc., resulting in a fine surface Concave and concave, poor exhaust: no cold slug well, etc.
3. In terms of mold processing technology, there are mainly the following four points.
A. The barrel heating is uneven, the barrel temperature is too high or the material temperature is too low, and the mold temperature is too low, which causes the rubber injection molded parts to condense and harden on the surface of the cavity prematurely and leave the mold surface, and the cavity surface roughness cannot be reproduced, and then tarnished.
B. The injection pressure is low, the injection speed is too slow, and the injection time is insufficient, resulting in poor sealing of plastic processing parts and affecting gloss
C. The injection rate is too large or too small.
D. The cooling time is too short, and the plastic injection molded parts are not cooled enough to make the surface fade. At this time, you should increase the gate, reduce the injection mold temperature and increase the cooling time.
4. Raw materials
A. The raw materials are not dried and contain volatile substances, which are easy to agglomerate on the surface when encountering a cool cavity, which prevents the melt from being in close contact with the mold surface.
B. Plastic degradation affects the color tone.
C. Excessive amount of auxiliary or mold release agent or poor quality, mixed with dust, causes the plastic injection molded parts to become fuzzy and dark, and pits.