Shanghai Daoqin Plastics Co., Ltd.

PC/ABS alloy （HAC series ） is types property can excellent engineering plastics, it improvement PC force cracking property, processing property, meanwhile tool has excellent heat resistant property, impact resistant property, chemical resistance and dimensional stability. flame retardant PC/ABS can to 1.5mm V0, 2.0mm 5VB and 3.0mm 5VA flame retardant rating, and using/adopting flame retardant, more green environmental protection. widely used in electrical 脑显示 device outer housing/shell and other IT product, parts, printing machine and other office equipment outer housing/shell.
Kumho day flame retardant PC/ABS can use processing equipment injection molding, extrusion molding, structure foaming molding and other. its features lower:  
 
无卤 flame retardant PC/ABS流变 features 图
     flame retardant PC/ABS due to has PC formed separation and flame retardant, small amount water separation easy 导致PC in high temperature molding processing process in generate hydrolysis, and separation hot （包括剪切 hot ）导致部 separation degradation and small separation 子析出, from formed products generate silver streaks, 发黄, surface strip/profile 纹, Color Difference and other appearance issues, and product 脆, filament fracture, cracking and other strong/high degree issues and mold 沉积模垢 and other defect. therefore, is molding more excellent product, 建议检查 injection molding related step/link, 请参考 below/following flame retardant PC/ABS injection molding processing process specification.
processing precautions:
1, must for material 进行充 separation drying, easy formed material hydrolysis;
2, control material molding temperature degree and in high temperature 时 滞留 time, easy formed material thermal degradation.
一, material drying:
    usually lower, PC/ABS resin in 储存运输 process in absorption gas in water separation, its water absorption gas wet degree 变化而变化, generally is 0.2～0.3% between. is make injection molding products to most 佳效果, decrease/reduce degradation can can property, PC/ABS in molding processing front must drying, make material water amount drop 至0.05% below/following, most good in 0.02% below/following, improve/increase material processing stability property can and mechanical properties. HAC series PC/ABS drying time and moisture content 关系见 lower 图:  
 
 
无卤 flame retardant PC/ABS drying time and water separation content trend 图
    usually, flame retardant PC/ABS resin in temperature degree lower （见 lower table/sheet ）, drying 4～6 small 时, can to need moisture content. specific drying time and use drying equipment has 关, most long drying time can ultra- 48 small 时, 否则材 material has degradation color can can.

无卤 flame retardant PC/ABS各 grade drying temperature degree table/sheet
 
 HAC8250NH HAC8250NH（M） HAC8250NH(H) HAC8290NH
drying temperature degree （℃）
 80-90
 80-90
 85-95
 85-95
 
drying equipment
     commonly used drying equipment has types: drying machine, material drying machine and remove wet drying machine
     use drying machine 时, will resin in pallet upper, thick degree is 25mm left right, thick. for/regarding large pellets （回 use material ） or glass fiber filling material material, drying time increase to 6 small above.
     use material drying machine 时, add 入 材 material need large material amount 50%而 small 于90%, ensure hot retardant force and drying efficiency, meanwhile need 监控出风 amount and 出风口 temperature degree, 进风口 and 出风口 temperature control in 20 degree inner, most good 10 degree inner. material 斗 容 amount must ensure material drying time to 4-6 small 时.
     use remove wet drying machine 时, remove attention/notes drying temperature degree, drying time and amount outer, also must control good 露点, most good is -40 degree, can high 于-30 degree, this can ensure drying 效果.
     HAC series flame retardant PC/ABS建议 use remove wet drying machine drying.
二, injection molding equipment selection:  
  in its injection molding equipment specifications 时, need made parts injection molding weight and clamping force this basic factors.

injection molding machine amount
    injection molding weight （ has type 腔, runner and 注道） and other injection molding machine most large injection molding amount 50~80%时, generally can obtain most 佳效果. use large material machine 时, small injection amount formed resin time necessary long, from 而导致 resin degradation. if must in temperature degree scope/range high temperature 段进行 injection molding, selection relatively small injection molding machine material amount, injection molding amount large most large injection molding amount 60%, shrink short material time, reduce material degradation can can property. 我们建议 most long hot time small 于10 separation 钟, most hot time small 于5 separation 钟.
coarse 略估算材 material time experience 公式如 lower:
 
 
its in x table/sheet screw most large amount
x1 代 table/sheet injection use amount
t table/sheet molding cycle
β positive 系数, according to product structure and equipment selection large small 取1.5～2.5

clamping force
   products clamping force 估算: clamping force （T） = 塑 parts 投影面积（c㎡) x plastics clamping force 常数（t/c㎡）, PC/ABS recommendation is 0.5-0.8, 而计算出 clamping force ultra- injection molding machine most large clamping force 85%.

screw
   is anti screw for material generate relatively strong/high 剪切而导致PC/ABS degradation, selection in low pressure shrink ratio screw. screw requirements lower: long ratio: 20:1-25:1; pressure shrink ratio: 2:1-2.5:1
 
三, injection molding process parameters setting:  
injection molding process parameters, is and temperature degree, speed degree, 位置, pressure and time has parameters. formed in comprehensive 考虑, need in can ensure products quality (如: appearance, dimensions degree, machine strong/high degree and other) and molding as rate (如: molding cycle) upper combined setting. HAC series flame retardant PC/ABS参考 molding process lower table/sheet:
table/sheet Kumho day 丽无卤 flame retardant PC/ABS各 grade main/primary molding process parameters table/sheet
project
  mono 位
 HAC8250NH
 HAC8250NH（M）
 HAC8250NH（H）
 HAC8290NH
 
drying temperature degree
 ℃
 80-90
 80-90
 85-95
 85-95
 
drying time
  small 时
 4-6
 4-6
 4-6
 4-6
 
mold temperature degree
 ℃
 50-80
 50-80
 50-80
 50-80
 
molding temperature degree
 ℃
 230-270
 230-270
 230-280
 240-280
 
 
    molding temperature degree setting is ensure PC/ABS充 separation is 基准, amount use low temperature 区域, anti material degradation. molding temperature degree increase obvious reduce flame retardant PC/ABS viscosity, increase resin flow property, 因而, make flow 距离变 long. upper, use molding temperature degree upper 限时, make 熔胶滞留 time can can short, degradation generate. use 手持式 high temperature 计, amount melt material temperature degree.
mold temperature degree
    mold temperature degree control for most made parts 充填程 degree, appearance, residual stress is non important. 我们建议 in molding PC/ABS时 use mold temperature machine control mold temperature degree, mold temperature is 50-80℃. relatively high mold temperature degree, 往往会 generate good flow, relatively high weld lines strong/high degree, relatively small product internal stress, molding cycle long. mold temperature degree ratio low, 就会导致 high internal stress loss bad made parts most property can. made parts surface and ring cycle 而言, mold temperature degree is temperature degree scope/range in value 时, can to relatively good 结果.

screw speed
     generally in cooling time inner amount formed amount setting screw 回转数（RPM）. meanwhile need 考虑材 material 塑化状态, screw 回转时发生 剪切 hot, amount time stability property and most small amount stability property. high screw speed 会导致 large hot, from make melt material temperature degree large large high setting temperature degree, has can can 导致材 material degradation. screw speed and screw outer has 关, flame retardant PC/ABS建议 most screw speed degree is 200mm/s, its speed through lower 面公式计算:

screw speed RPM=〔 most speed degree 200mm/s×60〕/〔D*π〕.

recommendation screw speed lower 图:
 
 
图三 screw speed 图 
back pressure
    back pressure function is improve/increase material quality, make material more and gas. back pressure 调校应视 raw materials property can, drying 情况, product structure and quality 状况而定, flame retardant PC/ABS back pressure generally in 3-10kg/cm2. high back pressure, 也会导致 large hot, injection molding need 留意. product surface has less silver streaks, mixed color, sink marks and product dimensions weight large 时, can increase back pressure; 当射嘴出现漏胶, 流涎, material hot separation understanding, product color and material slow can 考虑适当 decrease low back pressure.

松退
    is is anti 止熔胶流延而 setting screw most small rear amount, it can reduce material inner material pressure, decrease/reduce internal stress. amount and back pressure large small and structure and temperature degree related. back pressure relatively small can 不设松退 amount; usually 情况松退 setting is 2-5mm. large amount make material inner material gas 体,严 heavy effect/influence products quality.

most small amount
    amount 一方面 can anti screw and nozzle 接触发生 machine 械碰撞事故; 另一方面 can through material control injection amount heavy degree, to stability injection molding products quality 目. material amount small, 则达不 to 缓冲 目, easy 导致每次 injection molding quality unstable; large make 熔胶受 hot time long degradation. usually 建议残余 amount is 5-10mm.

injection molding speed degree
   selection injection molding speed degree 时, main/primary products appearance, mold gas and type inner resin flow retardant force. setting need 一边观察确认 products ﹐ slow slow more speed degree. relatively fast injection molding speed degree, generally make process/workflow add long, combined thin products, formed relatively good surface light degree. for/regarding gate and gate, fast injection molding speed degree generate strong/high 剪切导致材 material degradation, from 而出现 silver streaks, color, delamination and and other defect phenomenon, meanwhile mold gas need especially 通畅. slow speed injection molding speed degree more used for gate and gate made parts, can 帮助避免 gate 白晕, 喷射痕 and flow marks and other defect. for/regarding thick parts [5.0mm and above ], slow speed 充填, has decrease/reduce and 空隙. using/adopting separation 段阶梯式 speed degree setting, ensure 充填顺畅 and products appearance.

injection molding and holding pressure pressure
    injection pressure is is melt in flow process in retardant force, flow process in in retardant force need injection molding machine pressure 抵销, to melt 一定 充填 speed degree and for melt pressure 实, shrink,以 ensure process 顺利进行. injection molding pressure many amount has 关, 如: melt temperature degree, mold temperature degree, made parts 几何形状, thick, flow long degree, and its it mold and equipment 情况. 总之, most good selection can meet/satisfy property can, appearance and injection molding ring most low pressure. meanwhile need 关注实际 injection molding value pressure and setting value 差异, if value pressure to setting pressure, need heavy new optimization process parameters.

generally lower, combined holding pressure pressure is injection pressure 60～80%.

holding pressure time
    holding pressure time setting is according to gate cooling formed its solid 化﹐ screw again already again for molding product add pressure is time. holding pressure time setting injection shot time and pressure is 基准﹐然 rear 渐渐延 long time molding product weight, molding product weight again is is need setting holding pressure time

 
 
图四 products weight holding pressure time 变化图 
cooling time

cooling time setting is product solid mold opening rear generate deformation, can setting long 一点, rear according to product and cooling different slow slow decrease/reduce, product deformation most less cooling time is most cooling time. can lower 列公式估算:
 
 
式 in δ is need cooling products thick degree, mono is mm
α is plastics hot 传导系数
四, machine  
当 injection molding ring in 断时, according to machine time different different methods:
short 期: short 期（10～15 separation 钟）停 machine, HAC series flame retardant PC/ABS resin can in material inner, use 排出. material 筒采取保 temperature measures, temperature temperature degree is 150℃.
long 期: full remove material inner resin material, according to below/following standards machine steps as:
1. material material slip 阀, 继续按 cycle injection molding, to screw again rear 退.
2. 排出残留 material material. most good 进行清 machine 处理.
3. screw 应停留 in front 进位置, material add hot device.
 
五, machine  
    machine 时, material add hot device is positive processing temperature degree, temperature degree to rear again maintain 20 separation left right, for injection shot, to material material full 部排出, rear injection molding. 应检查开始 injection molding parts is by injection molding material 污染.
六, machine  
    high density polyethylene (PE), general purpose polystyrene (PS) and powder injection molding polypropylene (PP), is flame retardant PC/ABS most 佳清洗 agent. material can in processing temperature degree lower 清洗, rear 应逐渐 reduce temperature degree. in process in, combined 适 通风 non important.
七, use material （破碎 material ） 
    if application in use use material, can runner, water and non degradation made parts rear uniform add new material in, most high add amount small 于25%. material need remove powder 屑, control pellets dimensions is 7.9～9.5mm. due to powder ratio surface large, absorption water separation easy dry, easy products silver streaks; meanwhile powder hot easy degradation 炭化, products black spots defect.

    another, especially attention/notes maintain pellets 清洁, by its it material material 污染. due to use material and pure pellets dimensions different, water separation expand dispersion different, therefore, drying time need increase. use use material for color can can has effect/influence. 实际回 use material use, specific product requirements 而定.
 
八, Common defect guide
 
 
 
  
 
Common defect guide
defect phenomenon （★ is main/primary measures ）
sink marks ★ improve/increase pressure and holding pressure pressure, especially is holding pressure pressure
★ increase holding pressure time
★ adjustment material temperature degree, more is reduce temperature degree
★ adjustment mold temperature degree, mold temperature high generate large shrinkage, mold temperature low make holding pressure 失效
★ increase gate and runner
★ product or add strong/high thick degree thick, design
● reduce injection molding speed degree
● adjustment gate 位置
● selection shrinkage rate small material
weld lines ★ improve/increase pressure and holding pressure pressure
★ improve/increase material temperature degree
★ increase injection molding speed degree
★ improve/increase mold temperature degree
★ increase gate and runner dimensions, adjustment 位置
★ improve/increase material flow property
● increase mold gas
● decrease/reduce demolding agent use
●材 material drying separation
silver streaks ★ reduce material temperature degree
★充 separation drying material
★ reduce injection molding speed degree
★ reduce screw speed, adjustment combined back pressure
★ increase gate and runner dimensions, adjustment 位置
★ decrease/reduce screw amount
★ product design increase R角, make melt flow 顺畅
● increase mold gas
● decrease/reduce demolding agent use
●材 material mixed 入杂质 or material more
发黄, 黑斑 ★ reduce material temperature degree
★ reduce injection molding speed degree
★ decrease/reduce material time
★ decrease/reduce ring 境污染
★ improve/increase material heat resistant property
● increase mold gas
● decrease/reduce demolding agent use
●材 material drying separation
打不满 ★ improve/increase pressure and holding pressure pressure
★ improve/increase injection molding speed degree
★ improve/increase mold temperature degree
★计 amount 不够, increase add material amount
★ improve/increase material flow property
★ add large gate and runner large small
● increase mold gas
● decrease/reduce demolding agent use
●检查 injection molding machine ring is loss
flow marks ★ improve/increase material temperature degree
★ reduce injection molding speed degree
★ improve/increase mold temperature degree
★ improve/increase material flow property
★ add large gate and runner large small
● increase cold material 井
● decrease/reduce demolding agent use
● improve/increase holding pressure pressure
warpage deformation ★ reduce pressure and holding pressure pressure, especially is holding pressure pressure
★ decrease/reduce holding pressure time
★ adjustment material temperature degree
★ adjustment front rear mold temperature degree
★ adjustment gate and runner large small and 位置
★ mold cooling water design 不当, heavy new adjustment
● reduce ejection speed degree, adjustment ejection and 数
●延 long cooling time
● selection shrinkage rate small, orientation property small material
made parts 脆裂 ★ reduce pressure and holding pressure pressure
★ reduce material temperature degree
★充 separation drying material
★尽 amount less use material
★ increase product R角
★避免 product certain chemical product
● reduce back pressure and screw speed
● add large gate and runner large small, anti 止剪切 hot
● adjustment ejection, increase ejection 面积
flash/burrs ★ reduce pressure and holding pressure pressure
★ decrease slow speed degree
★ reduce material temperature degree
★修复 mold separation type loss 伤
★ improve/increase injection molding machine clamping force
● reduce mold temperature degree
● adjustment holding pressure 切换位置
喷射痕 ★ improve/increase material temperature degree
★ reduce gate injection molding speed degree
★ improve/increase mold temperature degree
★ improve/increase material flow property
★ add large gate and runner large small, adjustment 位置
● increase cold material 井
● decrease/reduce filling agent use
demolding defect ★ reduce pressure and holding pressure pressure
★ reduce ejection speed degree
★ improve/increase material temperature degree, use relatively low pressure molding
★ add large ejection 面积, adjustment 顶针位置
★ add large mold demolding degree
★延 long cooling time
●抛 light mold
● selection strong/high degree good material
● decrease/reduce product 尖角, 避免应 force in