注塑工艺参数优化

1、叮叮小文库培训课程 2工艺参数的优化受训者手册德马格注塑机工艺参数优化的步骤指导页面周期分析3注塑工艺参数优化6步骤1:找出转压点7步骤1结果8步骤2:找出保压时间（浇口冷凝时间）9步骤2结果10步骤3:优化注射速度11步骤3结果12步骤4:采用正确的螺杆转速13步骤4结果14步骤5:优化多级螺杆转速和背压曲线15步骤5结果16步骤6:优化松退17步骤6结果18步骤7:优化保压曲线19步骤7结果20TABULATED RESULTS21步骤8:优化锁模力22步骤8结果22步骤9:设定注射压力23步骤9结果23典型工艺参数公差设定2427成型周期分析. 然后去机床看正在运行的模具 , 写采用下面

2、表格估计注塑过程中的每一阶段对周期的影响 下实际的时间并计算出百分比 .哪一阶段在整个周期中占最多的时间 ?那里可以是最有效的缩短成型周期 ?模具1估计%实际实际%评价合模射台前进和后退注射时间保压时间冷却时间开模顶出整个成型周期100%seconds100%模具2估计%实际实际%评价合模射台前进和后退注射时间保压时间冷却时间开模顶出整个成型周期100%seconds100%工艺参数优化目标 :? 一步步改进工艺过程稳定性 .? 评估各个参数的更改对工艺过程稳定性的影响? to demonstrate the cumulative improvemnt in the process and p

3、roduct consistency方法:At each stage, after the process has been given sufficient time to stabilise, a run of sixteen consecutive mouldings is to be made. These mouldings will be assessed for consistency by weight (a dimension, a physical property or some other attribute could equally well be used, we

4、ight is simply the most widely applicable).稳定性通过计算重量的标准偏差来衡量 . 同时打印出机床 IBED 上的过程统计数据 .1. 找出转压点2. 找出浇口冷却时间3. 优化注射速度4. 采用正确的螺杆转速5. 优化多级预塑曲线6. 优化松推7. 优化多级保压曲线8. 优化锁模力9. 设定注射压力限定步骤1找出转压点在没有保压压力和保压时间的基础上填满产品95% -98%,然后设定一定的保压和保压时间生产16模.初始设置时的指导1采用行程切换2设定切换位置为10-12mm （逐步增加预塑量直到产品打满 95% - 98%的位 置）3设置注射压力为最

5、大值4设定保压压力和保压时间均为 05设定注射速度60 mm s-16设定松推速度为最大值7设定锁模力为最大值8选择适当的螺杆转速9根据材料物性表，设定料桶温度10配置过程统计控制11设定保压压力和保压时间生产完整的产品称12模产品的重量，计算标准偏差打印：页面20工艺参数优化页面50工艺过程统计步骤1结果输入实际值平均值范围最小最大没保压时的重量有保压后的重量填充的百分比%标准偏差（16模）g料垫（平均值和范围）预塑时间（平均值和范围）螺杆停止位置（平均值和范围）注射时间（平均值和范围）注射压力峰值,P inj. max转压压力,PN press.转压位置步骤 2找出浇口冷凝时间设定保压压力

6、为步骤 1 上找出的注射压力峰值的 50% 左右 . 设定保压时间为 1 s .生产数模产品使过程稳定后连续取 5 模产品称出每模重量和平均值 增加保压时间至 2 s, 生产数模产品使过程稳定后连续取 5模产品称出每模重量 在保压时间 3s, 4s 5s . . . 时重复上述过程直到产品重量不再增加 作出产品重量和保压时间的关系图 .记录 Record the TCU setting and the actual mould temperature. 打印:页面 30 温度XL Spreadsheet graph为什么记录模具温度很重要 ?还有什么因素会影响浇口冷凝时间 ?步骤2结果输入实际

7、值TCU sett ingFH temperatureMH temperatureCCC重量1重量2重量3重量4重量5平均重量时间保压重量1重量2重量3重量4重量5平均重量时间保压所需的保压时间步骤 3优化注射速度0.)采用多级注射曲线 , 使注射行程最后的 10-20% 采用逐步降低的注射速度 . 每次更改注射速度 , 必须重新建立转压点 . （注意每次保压和保压时间都设定为 连续取 16 模, 计算出标准偏差 .打印:页面 24 MWE 使用和没使用多级保压时的曲线页面 26 多级注射页面 50 工艺过程统计为什么转压点要更改 ?注射压力发生了什么 ?为什么在数社的末端采用逐步降低的注射速

8、度是有用的步骤3结果输入实际值平均值范围最小最大没有保压时的重量采用保压的重量填充百分比%标准偏差（16模）g料垫（平均值和范围）预塑时间（平均值和范围）螺杆停止位置（平均值和范围）注射时间（平均值和范围）注射压力峰值,P inj. max转压压力,PN press.转换位置步骤 4采用正确的螺杆转速Select the correct, optimum screw speed for the material being processed (see T.01 notes, Section 5 ). Use this single speed for the whole plasticisi

9、ng strokeSet a back pressure of 5 to 10 bar (hydraulic).Readjust dosing stroke to achieve 95-98% fillTake sixteeen consecutive mouldings and determine the standard deviation of the weights.Print out:Page 50 Process StatisticsWhy is it important to use the manufacturer s recommended screw speed?STEP

10、FOUR RESULTSIn sert actual values in the releva nt boxesMea n valueRangeminmaxWeight without hold ing pressureWeight with holdi ng pressurePerce ntage fill%Stan dard deviati on (16 shots)gMelt cushi on (mea n and ran ge)Dosing time (mea n and ran ge)Screw stop positi on (mea n and ran ge)Injection t

11、ime (mean and range)Peak injection pressure, P inj. maxIn jecti on pressure at cha ngeover, PN press.Chan geover strokeSTEP FIVEOptimise screw speed and back-pressure profileUse the Dosing Profile page to slow down the screw rotation speed for the last 10% of the metering stroke.Readjust dosing stro

12、ke to achieve 95-98% fillTake sixteeen consecutive mouldings and determine the standard deviation of the weights.Print out:Page 21 Dosing ProfilesPage 50 Process StatisticsWhat has happened to the Dosing Stop position?STEP FIVE RESULTSIn sert actual values in the releva nt boxesMea n valueRangeminma

13、xWeight without hold ing pressureWeight with holdi ng pressurePerce ntage fill%Stan dard deviati on (16 shots)gMelt cushi on (mea n and ran ge)Dosing time (mea n and ran ge)Screw stop positi on (mea n and ran ge)Injection time (mean and range)Peak injection pressure, P inj. maxIn jecti on pressure a

14、t cha ngeover, PN press.Chan geover strokeSTEP SIXOptimise decompressionFind the decompression speed which gives best screw stroke and melt cushion consistency. Set a decompression stroke of 5mm.Check that you still achieve 95-98% fill.Take sixteeen consecutive mouldings and determine the standard d

15、eviation of the weights.Print out:Page 21 Dosing ProfilesPage 50 Process StatisticsWhat has happened to the screw stop position?What is happening to the check ring?STEP SIX RESULTSIn sert actual values in the releva nt boxesMea n valueRangeminmaxWeight without hold ing pressureWeight with holdi ng p

16、ressurePerce ntage fill%Stan dard deviati on (16 shots)gMelt cushi on (mea n and ran ge)Dosing time (mea n and ran ge)Screw stop positi on (mea n and ran ge)Injection time (mean and range)Peak injection pressure, P inj. maxIn jecti on pressure at cha ngeover, PN press.Chan geover strokeSTEP SEVENOpt

17、imise holding pressure profileUse the Holding Profile page to set a holding pressure profile which ensures a smooth transition from injection to the holding pressure phase and use a high enough pressure to pack the part properly.Add a step which reduces holding pressure gradually to zero.Take sixtee

18、en consecutive mouldings and determine the standard deviation of the weights.Print out:Page 24 MWEPage 27 Holding ProfilePage 50 Process StatisticsWhy do you need a smooth transition from injection to holding pressure?Why bother to reduce the pressure gradually if the gate has already frozen?STEP SE

19、VEN RESULTSIn sert actual values in the releva nt boxesMea n valueRangeminmaxWeight without hold ing pressureWeight with holdi ng pressurePerce ntage fill%Stan dard deviati on (16 shots)gMelt cushi on (mea n and ran ge)Dosing time (mea n and ran ge)Screw stop positi on (mea n and ran ge)Injection ti

20、me (mean and range)Peak injection pressure, P inj. maxIn jecti on pressure at cha ngeover, PN press.Chan geover strokeTABULATED RESULTSIn sert actual values in the releva nt boxesThe range value, R, is the maximum minus the minumum, taken from the seven steps.1234567meanRmeanRmeanRmeanRmeanRmeanRmea

21、nRMelt cushionDosing timeScrew end positionInjection timeInjection pressure P hyd maxInection pressure PN hydraulicChangeover strokeStandard deviation (16 shots)Can you see a trend?Which step had the greatest effect on the con siste ncy of the mould ing?STEP EIGHTOptimisi ng the clamp forceReduce th

22、e clamp force by steps of 50 kN (100 kN for machi nes over 100 tonn es) using the setti ngs far optimised in the seve n steps above.Allow the process to stabilise each time and then weigh five mouldings.Tabulate your results below and plot a graph of tonn age aga inst part weight.Does the mould requ

23、ire the expected clamp force?What are the adva ntages of running at reduced tonn age?STEP EIGHT RESULTSIn sert actual values in the releva nt boxes En ter results in XL spreadsheet. Print out graph.Weight 1Weight 2Weight 3Weight 4Weight 5Mean weightClamp forcekNRequired clamp forceSTEP NINESet injec

24、tio n pressureUn til now the injectio n pressure has bee n set to the mach ine s maximum value. From the Process Statistcs page it can be seen that the machine does not need all that pressure to fill the mould.Gradually decrease the set injectio n pressure un til the injectio n time starts to in cre

25、ase.In crease the pressure aga in un til the previous injectio n time is established with a con siste ncy of 0.08 s or better preferably 0.02 to 0.03 s variati on.What is the purpose of limiti ng the inject ion pressure?STEP NINE RESULTSActual peak injectio n pressurebarSet injection pressurebarAppe

26、 ndix 1TY PICAL PROCESS TOLERANCESShot-weight deviati on0.05%0.1%0.2%0.4%Plasticising time0.04s0.06s0.08s0.13sInjection time0.02s0.02s 0.04s0.06sCycle time0.5% 0.5% 1%1%Screw positi on, dos ing stop0.1mm0.1mm0.2mm0.3mmMelt cushio n0.1mm0.1mm0.2mm0.3mmMelt temperature2 2 C 3 C 5 CMould temperature 1

27、C 1 C 2 C 4 CBarrel temperature 1 C 1 C 2 C 4 CFeed zone temperature 1 C 2 C 3 C 4 CHot runner temperature 1 C 2 C 3 C 4 CHydraulic oil temperature 1 C 1 C 2 C 2 CRoom temperature 2 C 2 C 3 C 4 CMould cavity pressure 3 bar 4 bar 6 bar 8 barPressure in tegral200300600900In ject ion filli ng pressure

28、1 bar 2 bar 3 bar 4 barHoldi ng pressure 1 bar 1 bar 1.5 bar 2 barBack pressure 0.5 bar 0.5 bar 1 bar 1 barFilling differences (Balanee of fill for each cavity) on multi-cavity tools 1% 1% 2% 5%Mould breathe0.01mm0.01mm0.02mm0.04mmChange over pressure (Pn Value) 1 bar 2 bar 3 bar 4 barScrew surface

29、speed 10mms -1 15mms -1 20mms -1 30mms -1Melt temperature peak value 0.3oC 0.4oC 0.5oC 0.6oCMelt temperature value at changeover 0.3oC 0.4oC 0.5oC 0.6oCThe achievable part quality is much in flue need by the con diti on of the material processed. It is importa nt that moisture content, proporti on of regrind and proporti on of colour (masterbatch) are con sta nt.Acceptable tolera nce