Shanghai Daoqin Plastics Co., Ltd.

using/adopting ASTM D 955－89 standards ABS plastics in process conditions lower injection molding shrink short rate, is 拟定公道 process conditions, 进行切确 process made and mold design, from production combined dimensions material to important 遵守.  
      plastics shrink short rate 直接关系 to products outer and dimensions degree. plastics products features, mold design, process conditions made and other effect/influence molding shrink short rate and rear shrink short formed separation, for injection molding products and its property effect/influence large 门. mold dimensions design is 独霸公役 belt/tape or uniform shrink short rate made relatively, mold in mold trial rear, 遵守试 made products dimensions mold, can is high hardness. low coarse degree mold dimensions 批改起 versus 当坚苦, therefore, meanwhile also can can can decrease for mold 批改, need 充实体味 molding shrink short rate process conditions 转变纪律, 预先切确测定 molding shrink short rate.

1, plastics 措置
ABS water absorption large is 0.2%-0.8%, for/regarding grade in addition ABS plastics , processing front use 烘箱以80-85℃烘2-4 small or use drying material 斗以80℃烘1-2 small 时. for/regarding 含PC组份 heat resistant grade ABS, dry temperature degree 适当调 high 至100℃, specific dry can use for extrusion 必定.
2, injection molding machine selection
can selection standards injection molding machine （ screw long ratio 20: 1, shrink short ratio large 于2, injection pressure large 于1500bar）. is using/adopting color masterbatch or products appearance material high, can selection small grade screw. clamping force 遵守4700-6200t/m2 必定, specific 需遵守 plastics and other and products 请求而定.
3, mold and gate design
mold temperature degree can is 60-65℃. runner 直径6-8mm. gate wide 约3mm, thick degree and products 一样, gate long degree need small 于1mm. gas wide 4-6mm, thick 0.025-0.05mm.
4, temperature degree
can use for injection method 切确剖断. and other separation 歧, temperature degree separation 歧, setting below/following:
impact resistant grade: 220℃-260℃, 以250℃ is 佳
electroplating grade: 250℃-275℃, 以270℃ is 佳
heat resistant grade: 240℃-280℃, 以265℃-270℃ is 佳
flame retardant grade: 200℃-240℃, 以220℃-230℃ is 佳
transparent grade: 230℃-260℃, 以245℃ is 佳
glass fiber (GF) add strong/high grade: 230℃-270℃
for/regarding 概况请求 high products, using/adopting relatively high temperature degree and mold temperature.
5, injection speed degree
anti grade need use slow speed, heat resistant grade use fast speed. products 概况请求 relatively high, need use high speed and more grade injection molding speed made.
6, back pressure
别景象 lower back pressure low good, 常常操 as back pressure is 5bar, color material use relatively high back pressure make mixed color uniform.
7, 滞留时刻
in 265℃ temperature degree lower, ABS in 熔胶筒 inner 滞留时刻 most more can ultra- 出5-6 separation 钟. flame retardant more short setting temperature degree low 至100℃, again use general purpose grade ABS清算熔胶筒. rear material need cold water in anti 止进一步 separation 化. from need use PS, PMMA or PE清算熔胶筒. has ABS products in rigid demolding 时并没 has issues issues, 一段时刻 rear has color, this more is hot or plastics in 熔胶筒勾留时刻太 long 激发.
8, products rear 措置
别ABS products rear 措置, has electroplating grade products 需经烘烤（70-80℃, 2-4 small 时）以钝化概况痕迹, but also electroplating products, products rear need packaging.
9, molding need positive 视 事项
has types and other ABS（出格 is flame retardant grade ）, in plastics raw materials 塑化 rear its 熔附出 force very large, long rear separation 化. 当闪现 upper 述景象时, need screw 均化段 and shrink short scratch 试, 并定期 use PS and other screw.
    （ propylene 膨丁二惭 styrene ） terpolymer （ABS） plastics comprehensive propylene chemical resistant product property, oil resistant property, rigid degree and hardness, butadiene tough property and resistant property and styrene electrical property can, by 广泛独霸于 automotive, electrical appliances table/sheet and machine 械财产 in, is general purpose engineering plastics in most product types 之一.
      outer for plastics molding research relatively 早, obtain 斗劲丰富 research 功效, inner from plastics molding shrink short rate research 并未几. is 以, using/adopting xsrn n oss－so standards ss plastics in separation process conditions lower injection molding shrink short rate, ABS plastics molding shrink short rate process conditions, is 拟定公道 process conditions 进行切确 process made and mold design from production combined dimensions products to important 遵守.