Under normal circumstances, the surface of plastic prod […]
Under normal circumstances, the surface of plastic products has good gloss and beautiful colors, but in the actual injection moulding production process, many car parts have relatively large defects in color and gloss, except for plastic materials, colorants and car parts. In addition to the rigid factors of Car Parts Mould surface finish, what other reasons can cause this situation?
(1) The finish of the car parts mould is poor, the cavity surface has rust, etc., and the mould exhaust is poor.
(2) The gating system of the car parts mould is defective. The cold slug well should be enlarged, the runner, polished main runner, runner and gate should be enlarged.
(3) The material temperature and mould temperature are low, and local heating of the gate can be used if necessary.
(4) The processing pressure is too low, the speed is too slow, the injection time is insufficient, and the back pressure is insufficient, resulting in poor compactness and dark surface.
(5) Plastics must be fully plasticized, but to prevent degradation of the material, be stable when heated, and adequately cooled, especially thick-walled.
(6) Prevent cold material from entering the workpiece, and use self-locking springs or lower the nozzle temperature when necessary.
(7) Too much recycled materials are used, plastics or colorants are of poor quality, water vapor or other impurities are mixed, and lubricants used are of poor quality.