注塑成型与模具知识.ppt

1、,注塑成型與模具知識介紹,Injection Molding Introduction,GOOD PART,Material 材料,設備與模具 Equipment and Tool,Processing 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 -

2、 80 % of Machine 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

3、求: F F(機台最大鎖模力)*85%,機器安裝尺寸確認: 1.機台噴嘴與模具澆口襯套尺寸:,Sprue Bushing 主流道衬套,Nozzle 喷嘴,Orifice 主流道孔口,Radius 半径,機器安裝尺寸確認: 備注:a.澆口襯套球形凹坑半徑R應比機台噴嘴球形頭半徑r大12mm b.澆口襯套注道小端直徑D應比機台噴嘴直徑d大1mm. 2.模具定位環尺寸: 比對機台與模具定位環尺寸. 3.模具外形尺寸與機台哥林柱間距. 4.機台模板鎖模螺絲與模具冷卻水管位置確認.,模厚與開模行程確認: 1.確認工式: Sk=Hm+H1+H2+a+510mm. Sk-注塑機模板全開距離(移動模板與固定模

4、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,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 Ra

5、tio压缩比 = hf / hm =2 2.5:1 (1.5 3 :1),Transition 过渡,L,D,150,100,50,25,50,75,125,150,100,Screw Dia in mm,RPM,SCREW 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 Mold,Provides Mechani

6、cal 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

7、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 射膠保壓,凝固及冷卻,塑膠塑化 加料松退,合模,開模頂出,Injection Molding 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 Inj

8、ection 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 Polymers,Raise Temperature of Polymer,T,G,Locked 固态 Entanglements,Stiff Flow 难于流动,Easier Flow 较易流动,Melt Temperature 熔融温度,Increased Melt Temperature yields increased Flow.提高熔融温度导致增加流动 However,

9、 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 Reciprocating Screw,(Filling

10、) Throat,Heating Coils,Nozzle,Hopper,Screw,Barrel,Force, 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 Moisture Le

11、vel: Less than 0.02% - 121 0 C/3 4 Hrs 水分含量小于0.02% - 121 0 C/3 4 Hrs,Drying Temperature-烘干溫度,Injection Molding Process,Part Cooling and Solidification,Hot Melt,Cooled Mold,Solid Part,制件冷却和固化,热熔体,温度较低的模具,固化的制件,Mold Temperature,Mold Temperature is critical in glossary and residue strain of part Unifor

12、m mold 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 Speed,1000 100 10,Injection Speed affects the viscosity of the molten material.,注射速度,表观粘

13、度,剪切速率,注射速度影响熔体粘度,Injection Molding Variables,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 Screw,Screw Rotation Feeds and Shears Material Into a Melt. Melt Collects Into Front of Barrel, Forcing Screw Back,Shot,Rotation 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

14、和背压,Injection Molding Equipment,Barrel Unit The Reciprocating Screw,Melt Required to Fill Mold Ready for Injection,Shot,Injection Pressure,注射压力,将要注入模具内的熔体 (3 5mm for PC),Injection Molding Variables,Cushion,Cushion,Material remaining in barrel when the ejection phase is completed. 注过程结束后，残于料筒前端的熔体 Th

15、e 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 Regrind can be Used Screen Sizes should be 7 to 9 mm,Injection Molding Regrind,对材料回收使用的建议,只使用未降解材料 回收料不能有污染 要象保存新料一样 通常允许添加20%的回收料 过滤网应该在7至9MM,Injection Molding Closing,Ten Do for Molding Engineering Resins,Know Your Material 了解你所使用的材料 Dry Properly 正确地干燥 Use Recommended Processing Conditions 使用推荐的加工参数 Use Properly Sized Equ