Shanghai Daoqin Plastics Co., Ltd.

in plastics injection molding processing in, parts thick is 一 十 separation key/critical parameters. thin 壁 injection molding parts has very more benefits, it reduce parts weight, production 规模, decrease/reduce material and shrink short molding cycle and other, is manufacturing thin product must using/adopting high speed injection molding machine, 甚不化算. 究竟传统 injection molding machine can 否胜任, is 你详尽 analysis.

    is thin injection molding? generally is in has 50cm² surface injection molding parts, its thick is lmm. this type of grade can is thin injection molding parts.
    however, injection molding machine 往往不 can thin injection molding requirements. 以一台 made as 3mm壁 thick parts machine is 例, 当熔化 hot plastics material front 沿部份流经 mold type 腔时, it will and temperature degree relatively low type or type inner 壁接触, formed solid thin table/sheet 皮. this type of front solid table/sheet large need 占整 壁 thick 20%.
    in this table/sheet inner 边, 注入 熔化材 material still in toward front flow. 显然, if parts thin decrease/reduce to “ thin 壁” degree, its cooling speed degree add fast, from 而导致 upper solid table/sheet 皮占整 壁 thick ratio/proportion will increase, is 说, its rear 续流人 type 胶 熔 melt “芯部” will shrink small. versus 反, parts generate cold time 间隔却 in shrink short. this to material flow increase difficult degree, from make parts in cold front achieve “填满” requirements more add difficult.
    is inner injection molding filling difficult, usually need for injection molding machine especially design or 改装, using/adopting more 通道注入口, add high 达241mpa injection pressure and 1, 000mm／s speed degree. however, this method will need versus can 观 资金.
    can in 传统 未经改装 standards injection molding machine upper, for certain process parameters control, achieve thin injection molding requirements 呢?
    is 肯定. 据报导, has in most large force is 90公吨, most large injection amount is 170g machine upper this 方面 实验. in this machine upper tool has 一 扇形注入口 inner parts and 一 注口,并 has type mold. inner parts long ／ thick ratio is 140:1, type thick degree is lmm. use resin is lexansp7602 polycarbonate (PC) and magunum9015.
    product parts weight, is can 变输出 value. in mold type conditions lower, parts weight 变化, and injection molding process 熔化材 material in type inner “填满” degree related. 据称, for parts weight analysis. its can degree can high 达95％. therefore 该实验就 is from has process parameters and parts weight 关系著手进行 research. is 此, in type especially 装设 五 pressure and temperature degree device. data system in inner pressure and temperature degree 曲线.
    该实验 using/adopting semi separation 数因子（halffractional factorial） design, use research nozzle temperature degree, mold temperature degree, cooling time, injection speed degree and pressure. 据称, this parameters can effect/influence parts weight. is this parameters 以确定 it for parts weight effect/influence, using/adopting different high low value combined （见 lower table/sheet ）, injection molding.

                            thin injection molding research can scope/range

        参  数         polycarbonate (PC)            abs
 
nozzle temperature degree (℃)         (290 - 300)         (260 - 280)
 
mold temperature degree (℃)         (80 - 90)           (68 - 80)
 
cooling time (s)          (40 - 50)           (25 - 35)
 
injection speed degree (mm/s        (203 - 272)         (229 - 272)
 
夹持 pressure (mpa)        (4.8 - 5.5)         (3.4 - 4.1)
 

      for pc and abs两 types material 进行 实验. conditions is: 各自 熔化 temperature degree; standards mold temperature degree and parts weight; standards parts force strong/high degree and most high use injection speed degree. another types material versus for degree can in different rate lower to 确立.
   
    实验结果如 lower:

    ● will abs材 material its temperature degree 260℃ rise 至280℃ for its parts weight 会由6.6g increase 至 7.4g, has 22％ increase large.
    ● for pc材 material, will 共熔化 temperature degree 由290℃ rise 至300℃时 parts weight from 7.3g increase 至8.9g, increase large 22％.
    ●当 mold temperature degree from 80℃ rise 至90℃时, pc and abs两 types material parts weight has increase large, 但pc more is 敏感, rear parts weight can from 8.4g increase 至8.8g, growth 4.8％.
    ●熔化 temperature degree and mold temperature degree 变化都会导致 parts force strong/high degree 改变. 但熔化 temperature degree increase high will make strong/high degree decline, mold temperature degree rise high make strong/high degree increase.
    ● shrink short cooling time and improve/increase injection speed degree will make pc材 material parts weight increase, 而abs材 material 则不受 this parameters effect/influence.

    analysis:

     ● for pc材 material 而言, temperature degree, mold temperature degree, cooling time and injection speed degree is effect/influence parts weight key/critical parameters; for/regarding abs． effect/influence its parts weight parameters is temperature degree and mold temperature degree.
     ●熔化 temperature degree rise high, will make material has more high hot can, meanwhile 会导致熔 melt degree reduce, from make melt material more easy flow, its formed more long long degree, meanwhile more add 顺畅 填满 type 胶. 但熔化 temperature degree high, will make material and drop grade. therefore, this parameters can in resin upper inner by use ensure type 胶 填满.
    ● mold temperature degree rise high, decrease resin in type cold 凝层, make melt material in type inner more easy flow, from obtain more large parts weight and more good surface quality.
    ● more short cooling time, can make 熔化材 material in container inner time more short decrease/reduce can can property. is, decrease/reduce thick 50％, will cooling time formed 4倍 decrease/reduce. another, cooling time formed 约70％ production cycle, it decrease/reduce production efficiency improve/increase.
    ● machine injection amount can can to most large value. is this 也帮助熔化材 material in container time decrease/reduce.
    ● increase high injection speed degree, make 熔化材 material versus for degree decline, this is due to 剪切变 more thin 时, generate false plastics 体（pseudoplastic） effect/influence 结果. meanwhile, this type of add hot, 仅发生 in to 一秒钟 瞬间, this for/regarding obvious 退化 说, is light heavy.
    ● injection speed degree improve/increase, although make pc材 material degree decline formed parts weight upper rise, ratio 起熔化 temperature degree increase high parts weight increase need less more. 不, due to it also can make material more add easy 退化, therefore, improve/increase injection speed degree also is has it can 取之处.
    injection speed degree 改变, for/regarding abs材 material 几乎不会造 formed effect/influence, this is due to it versus for degree has generate obvious decline 缘故. through in injection molding machine conditions lower for process parameters more, parts weight increase 效果. this 一结果实际 upper resin in 熔化状态 lower 填满lmm type can force increase is improve/increase thin molding can force.
    comprehensive 实验情况, in injection molding machine upper processing thin parts is can to. 进行操 as 时, can will its injection speed degree adjustment to most high 界限, in 此基础 upper, can according to material recommendation most high temperature degree and mold most high temperature degree standards, can can improve/increase this temperature degree parameters. this is in injection molding machine upper, low cost selection, achieve excellent thin 壁往塑 main/primary countermeasures.