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1、注塑成型與模具知識介紹Injection Molding IntroductionGOOD PARTMaterial 材料設備與模具 Equipment and ToolProcessing 工艺Design 设计好产品Equipment 设备-射出成型 機1.注塑量之選擇.2.鎖模壓力之確認.3. 機械安裝尺寸確認.4.模厚與開模行程確認5.頂出行程確認6.機台螺杆介紹机器注射容量選擇:(Machine Shot size)1.注塑量確定:G= 產品重(依3D計算)+料頭重( 依 流道計算) 2.與機台注塑量確認: 2-1.Part Weight = 30 - 80 % of Machine
2、 Shot Size 制件重量 = 30- 80% 机器 最大 注射量(實際) 2-2.機器最大注塑量(實際): 機器注塑容量(實際)=機器注塑容量(理論 )*PM/PPS 機器注塑容量(理論): 查機器參數. PM-使用原料比重. PPS-聚苯乙烯(PS) 常溫下的比重 (1.06g/cm3) 机器塑模力確定:(Machine Clamp Size)1.機台最大鎖模力選擇:依機台參數取得. 2.產品所需鎖模力計算:F=Q*S F-產品所需鎖模力.Q-模腔內注塑壓力須考量模腔內流道的壓力損力S-制品加上澆注系統在分型面上的總投影面積, cm2 3.標准要求:F=Hm+H1+H2+a+510mm
3、. Sk-注塑機模板全開距離(移動模板與固定模板之間的最大開距). Hm-模具厚度(mm).H1-頂出距離,通常等于型芯的高度 H2-制品高度,包括澆注系統在內 a-僅三板模具需取此值,為母模板與撥料板分開時的距離 510mm安全距離,當使用機械手時需取3050mm. 模具頂針行程與機台頂杆行程確認:機台頂杆行程:查機台參數可得,模具頂 針行程在模具LAYOUT上有標注.一般要求模具頂針行程小于機台頂杆 行程. S模具S機台 Uniform Plasticizing均匀塑化 Less Pressure Loss低压力损耗 Faster Cycles 更快成型周期Uniform Stock Te
4、mperature均匀储料温度 Streamlined Melt Flow线性熔融流动機台螺杆介紹作用:Metering 计量Feed 进料Screw and Cylinder Design 螺杆和料筒设计hf hm L/D = 20:1 (16 24 :1)Compression Ratio压缩比 = hf / hm =2 2.5:1 (1.5 3 :1)Transition 过渡 LD15010050255075125150100Screw Dia in mmRPMSCREW SPEED Suggestions推荐螺杆转速螺杆 直径转速往复式螺杆头结构 检查环类型: 止回环熔融树脂流过 开
5、放检查环检查环关闭, 防止在 注塑过程中料的回流建议采用止逆阀Standard Cylinder Nozzles 标准料筒喷嘴Heating Band 加热环Cylinder Bore料筒 主体To MoldProvides Mechanical and Thermal Connection From Hot Cylinder to Colder Mold 提供从热的料筒到相对冷的模具的机械和热连接到模具Injection Molding Process -注塑成型工 藝1.注塑成型流程.2.重要加工參數介紹:溫度: 料溫/模溫/烘干溫度.速度: 注塑速度/開合模速度/頂出速度.壓力: 注塑壓
6、力/ 開鎖模壓力/ 頂出壓力.3.成型十大原則注塑成型流程1.加料松退螺桿在料管內旋轉,將從料斗來的塑膠卷入, 並逐步將其壓實,排氣,塑化,融化塑膠不斷由 螺桿推向前端,並逐漸積存在頂端和噴嘴之 間,而螺桿本身受熔體的壓力而緩慢後移,當 積存熔體達到一次注射量時,螺桿停止移動.2.射膠當螺桿停止移動,在液壓缸或機械力作用下, 推動螺桿前進使熔体通過噴嘴注入模具.3.保壓當模具充滿后流動速度減慢,此時塑膠被繼 續擠入模腔,熔體密度提高.加壓流動模具充填加壓流動模具充填 射膠保壓射膠保壓凝固及冷卻凝固及冷卻塑膠塑化塑膠塑化 加料松退加料松退合模合模開模開模 頂出頂出Injection Moldin
7、g Process Important Process Variables 重要加工参数Melt Temperature 熔融温度 Mold Temperature 模具温度 Temperature Profiles 温度曲线 Residence Time 停留时间 Injection Speed 注射速度 Injection Pressure 注射压力 Pack Pressure 保压 Clamp Tonnage 锁模力 Cushion 缓冲料垫Model of Amorphous PolymersAdding Heat Increases Space 外热提供空间 Between Mole
8、cular Chains 在分子链之间Raise Temperature of PolymerTGLocked 固态 EntanglementsStiff Flow 难于流动Easier Flow 较易流动Melt Temperature 熔融温度35302520151050.030.060.090.120.150.180.210.240Wall Thickness in Inches壁厚(In)M e l tF l o w(in.)LEXAN?101 550 deg F.101 600 deg. FIncreased Melt Temperature yields increased Flo
9、w.提高熔融温度导致增加流动 However, Too High a Melt Temperature May Cause Degradation.但,过高熔融温度造 成降解How is heat added to the polymer? 外热如何作用于高分子材料Electrical Heat: 电加热 Heater Bands 加热带Mechanical Heat 机械热 Screw Speed 螺杆速度 Back Pressure 背压 Injection Pressure / Speed 注射速度/压 力Injection Molding Barrel Unit The Recipro
10、cating Screw(Filling) ThroatHeating CoilsNozzleHopperScrewBarrelForce, Torque From Injection Unit料筒组件回转式螺杆喷嘴螺杆加热料斗加料口料筒来自注塑单 元的力和力 矩Drying Drying temperature and time are an important key factor for good products in our production 在生产得到好的产品， 干燥温度和时间是 一重要因素 Good Parts 良品Typical Lexan (PC): 典型PC Moist
11、ure Level: Less than 0.02% - 121 0 C/3 4 Hrs水分含量小于0.02% - 121 0 C/3 4 HrsDrying Temperature-烘干溫度Injection Molding Process Part Cooling and SolidificationHot MeltCooled MoldSolid Part制件冷却和固化热熔体 温度较低的模具固化的制件Mold TemperatureMold Temperature is critical in glossary and residue strain of partUniform mold
12、 temperature reduces the effects of warpage. 均匀的模温可以减少翘曲Commonly controlled by water cooling channels. 模温通常冷却水孔道来控制Injection Molding Cooling模温模温对制件的光洁度和模塑残余应 力等级很重要Injection Molding Variables Injection Speed100010010100100010000LEXAN?141 644 deg F LEXAN?141 608 deg F LEXAN?141 572 deg FAp p a r en t
13、Vi scosity(Pa/s)Shear Rate (1/s)Injection Speed affects the viscosity of the molten material.注射速度表观粘度剪切速率注射速度影响熔体粘度Injection Molding VariablesInjection Pressure ProfileHy d ra ul icP ressureTimeFill TimeScrew Run TimeBack PressurePeak Injection PressurePressure Applied by Injection Ram to Force the
14、Plastic From the Barrel to the Mold.注射压力曲线注射压力峰值 液 压 压 力填充时间Injection Molding Barrel Unit The Reciprocating ScrewScrew Rotation Feeds and Shears Material Into a Melt. Melt Collects Into Front of Barrel, Forcing Screw BackShotRotation and Back Pressure 出量通过螺杆回转，熔体聚集 于料筒前部，反作用力使 螺杆后退。回转力矩 和背压Injection
15、 Molding Equipment Barrel Unit The Reciprocating ScrewMelt Required to Fill Mold Ready for InjectionShot Injection Pressure注射压力将要注入模具内的熔体 (3 5mm for PC)Injection Molding VariablesCushionCushionMaterial remaining in barrel when the ejection phase is completed.注过程结束后，残于料筒前 端的熔体 The injection molding process should allow a cushion to provide sufficient packing pressure in the mold缓冲垫注过程必须要有缓冲垫以保证 有效的保压REGRIND SUGGESTIONS Use Only Clean Non-degraded Uncontaminated Resin for Regrind Keep It As New Material Normally 20% of Regri
