Shanghai Daoqin Plastics Co., Ltd.

1, utilizing injection molding parts process production product 时, due to plastics in mold cavity in non-uniform cooling and non-uniform shrinkage and product structure design combined 理, easy product various defect: shrink 印, 熔接痕, gas 孔, deformation, 拉毛, 顶伤, flash. 2, is to high quality injection molding parts product, 我们必 must in design product separation its structure process property, lower combined injection molding parts product main/primary structure features analysis injection molding parts defect methods. 2.1 mold opening direction and separation type injection molding parts product in design 时首先 need its mold opening direction and separation type 线, ensure can can decrease/reduce machine and remove separation type for appearance effect/influence. 2.1.1 mold opening direction rear, product add strong/high 筋, 卡扣, and other structure can can design formed and mold opening direction 一致, 以避免抽芯 decrease/reduce 拼缝线, long injection molding parts mold lifespan. 2.1.2例如: 保险杠 mold opening direction generally is 车身坐标χ direction, if mold opening direction design formed and χ轴不一致, must in product in its 夹角. 2.1.3 mold opening direction rear, can selection separation type 线, improvement appearance and property can. 2．2 demolding degree 2.2.1适当 demolding degree can product 拉毛. light slip surface demolding degree large 于0.5 degree, fine surface large 于1 degree, coarse surface large 于1.5 degree. 2.2.2适当 demolding degree can product 顶伤. 2.2.3 deep structure product design outer surface degree requirements small inner surface degree, ensure injection molding parts injection molding parts mold type 芯不偏位, to uniform product thick, ensure product 开口部位 材 material density strong/high degree. 2.3 product thick 2.3.1 various plastics has 一定 壁 thick scope/range, generally 0.5～4mm, thick ultra- 4mm时, will cooling time long, generate shrink and other issues, 应考虑改变 product structure. 2.3.2壁 thick 不均会引起 surface shrink 印. 2.3.3壁 thick 不均会引起 gas and 熔接痕. 2.4 add strong/high 筋2.4.1 add strong/high combined application, can increase product rigid property, decrease/reduce deformation. 2.4.2 add strong/high thick degree must small product thick 1/3, 否则引起 surface shrink 印. 2.4.3 add strong/high mono degree large 于1.5°, 以避免顶伤. 2.5圆角2.5.1圆角太 small can can product force in, product cracking. 2.5.2圆角太 small can can injection molding parts mold type force in, type cracking. 2.5.3设置 combined 理 圆角, also can improvement injection molding parts mold processing process, type can use R刀铣 processing, 而避免 low efficiency electrical processing. 2.5.4 different can can 会引起 separation type 线 移动, combined 实际情况 selection different or 清角. 2.6孔2.6.1孔 形状应尽 amount simple, generally 取圆形. 2.6.2孔 轴 toward and mold opening direction 一致, can 避免抽芯. 2.6.3当孔 long ratio large 于2时, 应设置 demolding degree. 此时孔 直径应按 small dimensions （ most large dimensions ）计算. 2.6.4盲孔 long ratio generally ultra- 4. 2.6.5孔 and product 边缘 距离 generally large 于孔径 dimensions. 2.7 injection molding parts 模 抽芯 machine and 避免2.7.1当塑 parts mold opening direction can demolding 时, design machine 构. machine can molding complex product structure, easy product 拼缝线, shrink and other defect, increase injection molding parts mold cost shrink short injection molding parts mold lifespan. 2.7.2. design injection molding parts product 时, 如无特殊 requirements, amount 避免抽芯 structure. 如孔轴 toward and direction is mold opening direction, utilizing type type 芯碰穿 and other methods. 2.8一体铰链2.8.1 utilizing PP material tough property, can will design formed and product 一体. 2.8.2 as is film dimensions small 于0.5mm, maintain uniform, 2.8.3 injection molding parts 一体铰链时, gate can design in certain 一侧. 2.9嵌 parts 2.9.1 in injection molding parts product in 镶入嵌 parts can increase local strong/high degree, hardness, dimensions degree and small 螺纹孔（轴）, meet/satisfy various demand. meanwhile increase product cost. 2.9.2嵌 parts generally is copper, can is its it metal or plastics parts. 2.9.3嵌 parts in plastics in separation design and anti structure. 如: 滚花, 孔, 折弯, pressure 扁, and other. 2.9.4嵌 parts plastics 应适当 add thick, anti parts force cracking. 2.9.5 design parts 时, separation its in injection molding parts mold in methods （孔, 销, magnetic property ）2.10标识 product generally in product inner surface relatively 平坦处, using/adopting 凸起形式, selection method toward and mold opening direction can can 一致 面处设置标识, can 避免拉伤. 2.11 injection molding parts parts degree due to injection molding parts shrinkage rate non-uniform property and 不确定 property, injection molding parts parts degree obvious low metal parts, standards selection 适当 公差 requirements （OSJ1372-1978）2.12 injection molding parts parts deformation improve/increase injection molding parts product structure rigid property, decrease/reduce deformation. amount 避免平 sheet/plate structure, combined 理设置翻边, structure. combined add strong/high 筋. 2.13 gas injection molding parts 2.13.1 using/adopting gas injection molding parts, can improve/increase product rigid property, decrease/reduce deformation. 2.13.2 using/adopting gas injection molding parts, can shrink 印. 2.13.3 using/adopting gas injection molding parts, can Raw Materials, shrink short cooling time. 2.14 welding （ hot sheet/plate 焊, ultra- 声波焊, 振动焊）2.14.1 using/adopting welding, can improve/increase strong/high degree. 2.14.2 using/adopting welding, can product design. 3． combined 理考虑 process and product property can between 矛盾3.1 design injection molding parts product must comprehensive product appearance, property can and process between 矛盾. has 时牺牲部 separation process property, can to very good appearance or property can. 3.2 structure design in method injection molding parts defect 时, can can let defect in product 隐蔽部位. injection molding parts parts design key points 1, mold opening direction and separation type 线2, demolding degree 3, parts thick 4, add strong/high 筋5, and 孔6, machine and 避免7, parts deformation 8, 一体铰链9, parts 10, gas injection molding parts 11, comprehensive process property and parts property can