Shanghai Daoqin Plastics Co., Ltd.

injection molding parts molding processing front, plastics must by separation drying. has water separation material mold cavity rear, make made parts surface 出现银绦状 瑕斑, 甚至会 in high temperature 时发生 add water separation understanding phenomenon, make poor 化. therefore in molding processing front need for material 进行预处理, make material can maintain combined water separation. 　　1. mold temperature setting (一) mold temperature effect/influence molding cycle and formed quality, in 实际操 as in use most low mold temperature setting, rear according to quality 状况 适当调 high. (二) positive 确 说 method, mold temperature is in formed by 进行时 mold cavity surface temperature degree, in mold design and formed engineering conditions setting upper, important is not only 维持适当 temperature degree, also need can let its uniform distribution. (三) non-uniform mold temperature distribution, 会导致 non-uniform shrinkage and internal stress, make molding easy deformation and warpage. （四） improve/increase mold temperature can obtain below/following 效果; 1. add formed product crystallization degree and relatively uniform structure. 2. make molding shrinkage relatively separation, rear shrinkage decrease small. 3. improve/increase molding product strong/high degree and heat resistant property. 4. decrease/reduce internal stress 残留, separation toward and deformation. 5. decrease/reduce 充填时 flow anionic resistant, reduce pressure loss 失. 6. make formed product appearance relatively tool gloss and good. 7. increase molding product flash/burrs machine 会. 8. increase gate and decrease/reduce gate 部位凹陷 machine 会. 9. decrease/reduce combined obvious degree 10. increase cooling time. 　(一) in molding processing method, injection shot amount control (计 amount)以 and plastics uniform melt (can 塑化) is injection shot machine can machine 构(Plasticating unit 担任. 1. add hot temperature degree (Barrel Temperature) although plastics melt, large has 60~85% is is screw generate hot can, is plastics melt still large add hot temperature degree effect/influence, 尤以靠近 nozzle front temperature degree -- front temperature degree high easy 发生滴 material and made parts filament phenomenon. 　　2. screw speed (screw speed) (1) plastics melt, large is screw generate hot amount, therefore screw speed fast, has lower effect/influence: 1) plastics hot separation understanding. 2) glass fiber (GF) (add plastics) decrease short. 3) screw or add hot abrasion loss add fast. 　　(2)转 speed setting, can its speed (circumferen-tial screw speed) large small amount: speed =n(转 speed)*d(直径)*π(圆周 rate)　　 usually, low viscosity hot property good plastics, its screw 杆旋转 圆周 speed can setting to 1m/s upper lower, hot property plastics, low to 0.1 left right. 　　(3) in application in, can amount low screw speed, make 旋转进 material in mold opening front formed can. 　　3. back pressure (BACK PRESSURE)(1)当 screw 旋转进 material 时, to screw front 端 熔胶 蓄积 pressure is back pressure, in injection shot molding 时, can adjustment injection shot pressure 缸 退油 pressure adjustment, back pressure can has below/following 效果: 　　1)熔胶 more uniform understanding. 2) color agent and filling material more add uniform dispersion. 3) make gas 体由落 material 口退出. 4)进 material amount 准确. 　　(2) back pressure high low, is plastics viscosity and its hot property 决定, high back pressure make material time 延, 也因旋转剪切 force improve/increase, easy make plastics generate hot. generally 以5~15kg/cm2 is 宜. 　　4.松退(SUCK BACK, DECOMPRESSION)(1)杆旋转进 material rear, make screw 适当抽退, can screw front 端熔胶 pressure reduce, is 松退, its can anti nozzle 部 滴 material. (2)不足, easy make runner (SPRUE) mold sticking; more 松退, can 吸进空 gas, make molding product gas 痕. molding setting (一)事 front and setting 1.确认材 material drying, mold temperature and add hot temperature degree is by positive setting to can processing 状态. 2.检查开闭模 and ejection as and setting. 3. injection shot pressure (P1) setting in most large value 60%. 4. maintain pressure (PH) setting in most large value 30%. 5. injection shot speed degree (V1) setting in most large value 40%. 6. screw speed (VS) setting in 约60RPM. 7. back pressure (PB) setting in 约10kg/cm2. 8.松退约 setting in 3mm. 9. holding pressure 切换 位置 setting in screw 直径 30%. 例如φ100mm screw, setting 30mm. 10.计 amount ratio value short setting. 11. injection shot time short, cooling time long setting. 　　(二)手动运转 parameters positive 1.闭锁 mold (确认 high pressure upper rise), injection shot base/seat front 进. 2.以手动 injection shot to screw full 停止, attention/notes 停止位置. 3. screw 旋退进 material. 4.待 cooling rear mold opening molding product. 5. heavy 复⑴~⑷ steps, screw most 终停止 in screw 直径 10%~20% 位置, but also molding product short 射, flash/burrs and whitening, or cracking and other phenomenon. 　　(三) semi 自动运转 parameters positive 1.计 amount 行程 修 positive [计 amount 终点] will injection shot pressure improve/increase to 99%, holding pressure is 0, will amount 终点S0 toward front to short 射, again toward rear 调至发生 flash/burrs, its in is selection 位置. 2.出 speed degree positive PH回复 to water 准, will injection shot speed degree upper lower adjustment, 找出发生 short and flash/burrs speed degree, its in is speed degree [本 stage/phase can 进入以 more speed degree for appearance issues parameters setting ]. 3. maintain pressure positive upper lower adjustment maintain pressure, 找出发生 surface and flash/burrs pressure, its in is selection holding pressure. 4. holding pressure time [or injection shot time ] 修 positive 逐步延 long maintain time, molding product weight obvious stability is selection. 5. cooling time positive 逐步调 drop cooling time, 并确认 lower 列情况 can meet/satisfy: (1) molding product by ejection, 夹出, 修整, plastics bottle packaging whitening, or deformation. (2) mold temperature can balanced stability. thick 4mm above products cooling time easy method: 1)理论 cooling time =S(1+2S). mold temperature 60 degree below/following. 2)理论 cooling time =1.3S(1+2S). mold 60 degree above [S table/sheet molding product most large thick ]. 　　6.塑化 parameters positive (1)确认 back pressure is need adjustment; (2) adjustment screw speed, make amount time short cooling time; (3)确认计 amount time is stability, can adjustment add hot temperature degree degree. (4)确认 nozzle is has material, runner is 否发生猪尾巴 or mold sticking, formed product has gas and other phenomenon, adjustment nozzle temperature degree or 松退距离. 　　7.段 holding pressure and more speed active use (1) generally 而言, in effect/influence appearance lower, injection high speed is 原则, in through gate and holding pressure front relatively low speed 进行; (2) holding pressure using/adopting decline, 以避免 molding product internal stress 残留太 high, make molding product easy deformation.