Shanghai Daoqin Plastics Co., Ltd.

        Q: injection molding PP化妆 box/case deformation how to solution?

        ① isotactic polypropylene in 甲基排列 and its separation 子链 同一侧, is non type long polymer/macromolecule. and 链折叠 for its crystallization degree effect/influence large, its separation high degree 规整, crystallization degree large, shrinkage rate large, is 1.6%~2.0%, therefore formed pp in molding in rear shrinkage shrink 坑, deformation difficult solution.

        ② 化妆 product box/case structure mold usually 会出现 non large 转折角, 导致pp melt 紊流, add upper mold has 斜顶, water 道 不 combined distribution, its molding product in separation orientation 不一致, force in, from 而导致 deformation.

        ③ 化妆 product box/case design usually its 交口 隐蔽 property, using/adopting system, cooling system, ejection system very complex, product molding unstable deformation.

         solution methods lower:

        ①  process

        总体 upper 说, is need decrease/reduce molding rear shrinkage

        (1) material material molding temperature degree need again its material 规定 熔 melt scope/range inner, in effect/influence its filling stage/phase lower, temperature degree amount low

        (2) in holding pressure molding lower, need ensure 充足 补 shrink can force, is shrink stage/phase rear holding pressure pressure amount low, 避免应 force in

        (3) cooling stage/phase is most key/critical, use material material property can low mold temperature. in molding process in, need mold inner hot and cooling non-uniform, inner cooling temperature 差不应该 ultra- 10%

        ② QA

        (1)首样, polypropylene (PP) in cooling rear still force 释放, has can can deformation, therefore need and other its separation cooling rear again amount

        (2)SPC and in process QA non important, this data need 即时反馈 to technology 部门. spc in ucl and lcl made need according to product 实际情况 made 定

        (3)outgoing QA need to 零失误

        ③ process 验证

         process need for deformation product positive experiment/testing, from to data 以进行 rear process optimization and 改模建议.