Shanghai Daoqin Plastics Co., Ltd.

shrinkage is plastics processing 商们面临 large 敌, especially is for/regarding surface quality requirements relatively high large type plastics products, shrinkage more is 一 顽疾. therefore development various technology, most large degree decrease/reduce shrinkage, improve/increase product quality. 　　 in injection molding parts plastics parts relatively thick 位置, 如筋肋 or 突起处形 formed shrinkage need ratio 邻近位置 more heavy, this is due to relatively thick cooling speed degree need ratio 周围区域 slow more. cooling speed degree different 导致连接面处形 formed 凹陷, is 人们 熟悉 shrinkage 痕. this type of defect heavy made plastics product design and molding, especially is large type thick products electrical machine machine housing/shell and device outer housing/shell and other. upper, for/regarding day use electrical appliances this type requirements product upper must remove shrinkage 痕, for/regarding toys and other surface quality requirements high product has shrinkage 痕 存 in. 　　形 formed shrinkage causes can can has or more, processing methods, parts 几何形状, material selection and injection molding parts mold design and other. its in 几何形状 and material selection usually Raw Materials supply 商决定, 且不太容 easy 改变. is injection molding parts mold manufacturing 商方面 also has very more about/regarding injection molding parts mold design factors can can effect/influence to shrinkage. cooling runner design, gate type type, gate dimensions can can generate multiple 效果. 例如, small gate tube/pipe gate ratio gate cooling fast more. gate 处 早 cooling decrease/reduce type inner filling time, from increase shrinkage generate rate. for/regarding molding 工人, adjustment processing conditions is solution shrinkage issues types methods. filling pressure and time significantly effect/influence shrinkage. parts filling rear, more 余 材 material filling to type in 补偿材 material shrinkage. filling stage/phase short will 会导致 shrinkage add 剧, most generate relatively more or relatively large shrinkage 痕. this type of methods 本身也许并不 can will shrinkage decrease/reduce to water 平, is molding can adjustment filling conditions improvement shrinkage 痕. 　　 also has types methods is injection molding parts mold, has types simple solution methods is 修改常规 type 芯孔, is can this methods suitable for has resin. another, gas 体辅助 methods value 一试. 　　柱, gas and foam 　　 GE polymer processing research in 心(PPDC)进行 一项12 month research, assessment 8 types different in decrease/reduce shrinkage methods. this technology table/sheet decrease/reduce shrinkage 痕 一 most new 思路. this methods can separation is type: type can is 取代材 material method, type is remove hot amount method. 取代材 material method is through increase or decrease/reduce can can shrinkage 区域 材 material use amount decrease/reduce shrinkage 痕. remove hot amount method in fast speed will can can generate shrinkage hot amount remove, from decrease/reduce relatively thin and relatively thick generate cooling can can property. 　　 in research in, assessment 5 types 取代材 material method: 伸出式凸柱, 圆头凸柱, belt/tape elastic 簧凸柱, gas 体辅助 molding and chemical foaming. types remove hot amount method: 铍- copper 凸柱, 铍- copper parts and design hot active 动凸柱. assessment for is 待试部 parts in generate shrinkage 痕 数 amount, 待试部 parts is belt/tape has 三角形凸起 products. has methods comparison standards is standards tool ——不锈钢凸柱. testing tool can generate thick is 2.5mm 圆盘, high is 22.25mm, is 4.5mm, thick is 1.9mm, in upper has 2mm iron. 　　 research use molding equipment is 350t water 平触动 liquid pressure machine, material is day use electronics product in commonly used material, is shrinkage issues heavy material, 即GE PC/ABS, Cycoloy CU6800 and PPE/PS, Noryl PX5622. this types material processing scope/range in product technology parameters scope/range in 间点. if shrinkage 痕处于 most small 状态, can lower filling amount more more shrinkage 痕, 以方便 degree amount and experience methods comparison. tube/pipe shrinkage usually is through 肉眼 观察, is this experiment/testing using/adopting types machine for shrinkage deep degree 进行 定 amount amount. 　　 experiment/testing inner 容　　 experiment/testing standards technology is 伸出式凸柱, standards 凸柱伸出进入凸柱底部 壁里, from decrease small thick 并补偿凸柱 in more material formed 效果. experiment/testing in using/adopting types deep degree, separation is thick 25% and 50%. another experiment/testing using/adopting types 圆头而不 is 尖头 凸柱. this methods is remove 凸柱区域 材 material, is make 各区域 渡 more add 连贯. also has types methods in ejection sheet/plate and between use elastic 簧. elastic make parts cooling rear 凸柱底 lower material still pressure 状态, make material obtain shrinkage 效果. 结果会受 to elastic 簧初始 pressure and elastic 簧“ rigid property ” effect/influence, experiment/testing assessment this types factors effect/influence. use types different rigid degree elastic 簧, for types rigid degree elastic 簧都施 add multiple different pressure. 　　 　　 chemical foaming agent in experiment/testing assessment inner 容里, is chemical foaming agent advantages in use for tool 进行任何改变. methods based on is in relatively thick 区域也就 is most can can generate shrinkage foaming, foaming process generate local pressure retardant shrinkage. 当然, in foaming process in can use a small amount of (0.25%) foaming agent (Safoam RPC-40), 以免形 formed cracks loss parts surface. 　　 through processing injection nitrogen gas experiment/testing gas 体辅助 molding, nitrogen gas in usually easy shrinkage 区域形 formed bubbles, this can remove 该区域 材 material use bubbles gas filling 该区域. 　　 is achieve hot amount fast speed 转移, use types 由铍- copper formed 凸柱, hot speed degree ultra- 不锈钢材 material. technology requirements rear and large hot 池连接, make hot amount can full from 凸柱 区域 remove. methods types methods is utilizing standards 不锈钢凸柱但 is in 凸柱周围区域安装铍- copper parts. this requirements for injection molding parts mold type 腔进行充 separation 修改, in 该区域 processing small 槽安装筋肋/凸柱 structure. 筋肋/凸柱 structure processing formed 独立 铍- copper type parts, in small 槽里. hot speed rate high parts will 凸柱区域 hot amount full absorption 并导入 to tool in. front types methods using/adopting is by hot remove methods, “ hot active 动凸柱”包含 一 types will hot hot amount belt/tape dispersion to cooling plant/unit. 　　结果 comparison 　　 using/adopting PC/ABS材 material 时, experiment/testing methods generate shrinkage ratio standards generate shrinkage less. has remove hot amount methods very good, 取代材 material methods in has add elastic 簧 凸柱 methods ratio standards 凸柱效果 good, elastic 簧 预 add pressure for property can effect/influence is 突出. gas 体辅助 methods 结果不 is property: use types injection molding parts mold and material, due to products thin, melt - cooling speed degree fast, from gas 体渗透 very difficult maintain 一致. foaming experiment/testing has property effect/influence. parts surface obvious cracks table/sheet 明, in methods also can and other methods versus 提并论之 front, decrease/reduce foaming agent amount. 　　 use PPE/PS resin 时, add elastic 簧 凸柱同样 performance color. other types 取代材 material methods, 包括伸出式凸柱 method and gas 体辅助 molding method 效果也 ratio standards 凸柱 效果 good. for/regarding remove hot amount method, has 铍- copper methods ratio standards methods good. 　　而圆头凸柱 methods for/regarding types material 效果都不 good. outer is 伸出式凸柱 methods for/regarding PC/ABS材 material 而言效果 very good, 而二十 year, 伸出式凸柱一直 is recommendation methods. this experiment/testing table/sheet this methods for/regarding different material 而言效果并不 is same. 　　 most has 趣 结果 also is add elastic 簧式凸柱 methods. for/regarding types material 而言, use elastic 簧 预 pressure, products shrinkage property to 50% improvement. elastic property effect/influence 似乎不如 elastic pressure effect/influence large. pressure small, plastics melt will 凸柱 背端推 太远, 导致凸柱区域太 more material 滞留, from 而导致 shrinkage. elastic pressure large, in melt pressure lower by pressure shrink, and standards 凸柱一样. amount structure shrinkage 痕时, elastic add methods also 显示 惊人 结果. tube/pipe methods in will 凸柱附近 shrinkage most small 化, processing PPE/PS材 material 时, versus 连 筋肋 structure shrinkage to improvement. can can is pressure shrink has will material filling 进筋肋 structure, from decrease/reduce shrinkage.