Shanghai Daoqin Plastics Co., Ltd.

         injection molding 模 排 gas is mold design in important issues, especially is in fast speed injection molding in, for injection molding 模 排 gas requirements more add 严格.

        (1) injection molding in gas 体 源

        1)浇注 system and mold type in has gas.

        2) has raw materials has by drying troubleshooting water separation, it in high temperature lower gas formed water gas.

        3) due to injection molding temperature degree high, certain property unstable plastics separation understanding generate gas 体.

        4) plastics raw materials in certain additives or versus chemical reaction formed gas 体.

        (2)排 gas defect 危害

         injection molding 模 排 gas defect, will to parts quality and other more belt/tape series 危害. main/primary performance lower:

        1) in injection molding process in, melt will type in gas 体, if gas 体排出不 and 时, will formed melt 充填困 difficult, formed injection amount 不足而不 can type 腔.

        2) troubleshooting gas in type inner formed high pressure, in pressure shrink degree lower plastics internal, formed gas 孔, 空洞, hydrophobic 松, and other quality defect.

        3) due to gas by high degree pressure shrink, make type inner temperature degree upper rise, 进而引起周围 melt separation understanding, 烧灼, make parts local carbon and phenomenon. it main/primary in melt combined 流处, *角 and gate 凸缘处.

        4) gas troubleshooting 不畅, make 进入各 type melt speed degree different, therefore easy formed flow and combined 痕, make parts force property can reduce.

        5) due to type in gas retardant 碍, reduce speed degree, effect/influence molding cycle, reduce production efficiency.

        (3)塑 parts in bubbles distribution

         type in gas 体 源 main/primary separation type, type in 积存 空 gas; raw materials in separation understanding generate gas 体; raw materials in water water gas, due to different generate bubbles 位置也 different.

        1) mold cavity in 积存空 gas generate bubbles, distribution in and gate versus for upper.

        2) plastics raw materials in separation understanding or chemical reaction generate bubbles 则沿塑 parts thick degree distribution.