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1、OLE Technology Corporation徐徐 昌昌 煜煜Charles Hsu歐磊科技股份有限公司歐磊科技股份有限公司OLE Technology Corporation塑膠射出成型問題和模具的關(guān)係塑膠射出成型問題和模具的關(guān)係 Mold Related Plastic Injection Molding ProblemsOLE Technology CorporationConcentric record groovesOLE Technology Corporation流流 痕痕 Flow Line or Flow Mark流痕(Flow Line or Flow Mark)的定

2、義:成型品表面的線狀痕跡,此一痕跡顯示了熔膠流動的方向。OLE Technology CorporationRecord GroovesFlow front cools down near the wallCooled down outer layer impedes direct frontal flow to the wallFlow front touches mold wall againOLE Technology Corporation模模 具具1. 模溫太低模溫太低會使得料溫下降太快,射壓和保壓不足以將冷凝的表皮緊壓在模面上,留下熔膠在垂直流動方向的縮痕, 狀如年輪。提高模溫,保

3、持較高料溫,射壓和保壓將冷凝層緊壓在模面上,直到製品定型,流痕無由產(chǎn)生。模溫可從材料廠商的建議值開始設(shè)定。 每次調(diào)整的增量可為 6 C,射膠10次,成型情況穩(wěn)定後,根據(jù)結(jié)果,決定是否進(jìn)一步調(diào)整。 流流 痕痕 Flow Line or Flow MarkOLE Technology Corporation 模模 具具 2. 澆道(Sprue)、流道(Runner)或/和澆口(Gate)太小澆道、流道或/和澆口太小,流阻提高,如果射壓不足,熔膠波前的推進(jìn)會愈來愈慢,塑料會愈來愈冷,射壓和保壓不足以將冷凝的表皮緊壓在模面上,留下熔膠在垂直流動方向的縮痕, 狀如年輪。以CAE在電腦上對不同的熔膠傳送系

4、統(tǒng)(包括澆道、流道和澆口)的充填進(jìn)行模擬分析,找出理想的澆道、流道和澆口的尺寸(包括長度和斷面有關(guān)尺寸如直徑等),是可行之道。流流 痕痕 Flow Line or Flow MarkOLE Technology Corporation矩形邊緣澆口設(shè)計(jì)矩形邊緣澆口設(shè)計(jì)Rectangular Edge Gate DesignL = 0.5 0.75 mmW = 澆口寬度 ( mm ) gate width in mmA = 型腔表面積 ( mm ) surface area of cavity in mmn = 材料常數(shù) material constant 0.6 for PE, PS 0.7 f

5、or POM, PP 0.75 for ABS 0.8 for CA, PMMA, PA , PC 0.9 for PVC22h = n th = 澆口厚度( gate thick. in mm )t = 零件壁厚( wall thick. in mm )WtLh30AnW OLE Technology Corporation充填時(shí)間長將產(chǎn)生流痕充填時(shí)間長將產(chǎn)生流痕 Flow Lines due to Long Fill Time 凸片澆口厚度為 1.5 mm側(cè)壁厚度為 3 mmPCOLE Technology Corporation流道尺寸設(shè)計(jì)流道尺寸設(shè)計(jì) (1) Runner Sizing

6、 (1)D : 流道直徑 ( mm ) runner diameter in mmW: 下游塑膠重量 ( g ) downstream plastic weight L : 流道長度 ( mm ) runner length in mmDWL3.74OLE Technology Corporation流道尺寸設(shè)計(jì)流道尺寸設(shè)計(jì)(2) Runner Sizing (2)OLE Technology Corporation流道尺寸設(shè)計(jì)流道尺寸設(shè)計(jì)(3) Runner Sizing (3)mmDgcmcmcmgWmmLLWD338. 214.144102 . 0/9 . 0307 . 31223114

7、111OLE Technology Corporation流道尺寸設(shè)計(jì)流道尺寸設(shè)計(jì)(4) Runner Sizing (4)mmDgggcmcmcmgWWmmLLWD533. 466.28219. 014.14243 . 03/9 . 0807 . 322231224222OLE Technology CorporationOLE Technology CorporationHHSSHSL508. 010cos2210cosHHSWSW088. 0508. 010sin10sin10sinH/2 (L)OLE Technology Corporation5432654321AAAAandAAA

8、AAAA2221349. 0294360160HHRA22022. 022088. 022HHHHWA222088. 0022. 044HHA26508. 02508. 0222HHHHSA22621945. 0508. 0088. 0349. 04HHAAAAOLE Technology CorporationSWArcP41HRArc396. 123601601HHHSW596. 0508. 0088. 0mmDHmmDH533. 4338. 22211HHHP780. 3596. 04396. 1HHHPADH780. 3945. 0442OLE Technology Corporati

9、on比較圓形流道截面積(AR)與改良型梯形流道截面積(AT)。假設(shè)圓形流道的直徑與改良型梯形流道的高度相等。Comparing the cross-sectional area of full-round runner(AR) and the one of modified trapezoidal (AT),when the diameter of the round runner and the height of the trapezoidal runner are the same. %38.20785. 0785. 0945. 0945. 0945. 0785. 042222RRTTR

10、AAADHADDAOLE Technology Corporation換言之,改良型梯形流道所使用的材料比圓形流道的材料多了20.38%。In other words,modified trapezoidal runner uses 20.38% more material than full-round runner does.OLE Technology Corporation3. 排氣(Venting) 不足排氣不良,會使得熔膠充填受阻,熔膠波前無法將冷凝的表皮緊壓在模面上,留下熔膠在垂直流動方向的縮痕, 狀如年輪。在每一段流道末端考慮排氣,可以避免氣體進(jìn)入型腔。型腔排氣更不能輕忽。 最

11、好採用全周長排氣。CAE模擬熔膠充填,可以幫我們很快的找到所有可能的最後充填處(Last Filled Area),也就是須要加排氣孔的地方。 按圖索驥,萬無一失。模模 具具流流 痕痕 Flow Line or Flow MarkOLE Technology Corporation為何排氣仍然還是一個(gè)問題?Why venting is still a problem ?因?yàn)榻档蜕渌?,讓積風(fēng)有較多的時(shí)間逃氣,是一件太容易的事。但是Because it is too easy to slow down the injection speed and give the trapped air mor

12、e time to escape. But .排氣排氣VentOLE Technology Corporation射速一降,熔膠溫度很快降低,射壓必須提高,殘餘應(yīng)力隨之提高,翹曲的可能性增加。 如果想藉提高料溫,以降低射壓,料溫必須升得很高,這樣又會引起塑料裂解。When injection speed is lower, melt temperature goes down very fast, injection pressure has to be increased, residual stress is increased and the possibility getting wa

13、rppage becomes higher. If one would like to increase barrel temperature to reduce the required injection pressure, the barrel temperature has to be increased to a quite high level and polymer degradation would be induced. 排氣排氣VentOLE Technology Corporation有了適當(dāng)?shù)呐艢猓渌倏梢蕴岣?,充填和保壓可達(dá)良好狀態(tài),不須過度增加料管和噴嘴的溫度。Wi

14、th proper venting, the injection speed could be increased to achieve good fill and pack conditions, without having to raise the barrel and nozzle heats, improperly.排氣排氣VentOLE Technology Corporation深度(depth) : 1. 0.075 mm易流塑料(easy-flow mat.) 2. 0.125 mm難流塑料(stiffer-flow mat.)3. 深度深到流道末端見毛邊為準(zhǔn) (deep e

15、nough to feel flash at runner end)寬度(width) : 和流道同寬(as wide as runner dia.)排氣唇部(vent lip): 1.5mm A1拋光(finish)排氣通道通大氣(vent channel to atmosphere): 1mm深(deep)流道排氣流道排氣Runner VentsOLE Technology Corporation流道排氣流道排氣Runner VentsOLE Technology Corporation深度(depth) : 參照廠商建議 (refer to manufacturers recommend

16、ation)寬度(width) : 全圓周長(whole perimeter) or 5mm/25mm長度(length) : 1.5mm or 1mm A1拋光(finish)排氣通道通大氣(vent channel to atmosphere): 1mm深(deep)分模面排氣分模面排氣Parting Line VentsOLE Technology Corporation分模面排氣分模面排氣Parting Line VentsOLE Technology CorporationMaterial: PC-GFOLE Technology Corporation深度(depth) : 參照廠

17、商建議 (refer to manufacturers recommendation)寬度(width) : 全圓周長(whole perimeter)長度(length) : 1.5mm排氣溝(vent groove): 1mm深(deep)頂出銷或心型銷排氣頂出銷或心型銷排氣Ejector and Core Pin VentsOLE Technology CorporationVENTING GUIDELINES FOR FULLY OPTIMIZED MOLDS POLYMERDEPTH OF VENT (mm)EASY FLOWSTIFF FLOW GLASS FILLEDABS, S

18、AN, HIPS0.05080.0762Acetal0.01270.0381Acrylic0.05080.0762Cellulose/Acetate/Butyrate0.02540.0381Nylon 6/60.0127Nylon 6/6 13% Glass0.01270.0381Polyallomers0.01270.0254Polycarbonate0.03810.0762Polyethylene0.02540.0508Polypropylene0.02540.0508Polyphenylene Oxide0.02540.0762Polyphenylene Sulfide0.0127Pol

19、ysulfone0.0254Crystal Polystyrene0.02540.0508Polyvinylchloride (Rigid)0.02540.0762Polyvinylchloride (Plasticized)0.02540.0508OLE Technology Corporation噴流噴流 JettingOLE Technology Corporation噴流噴流 Jetting噴流(Jetting)的定義:自一受限區(qū)域(例如噴嘴或是澆口),到一較厚和開闊的區(qū)域,形成的彎曲摺疊似蛇的流痕。 OLE Technology Corporation 模模 具具 1. 澆口位置不當(dāng)

20、澆口位置不當(dāng)時(shí),塑流在型腔有自薄流向厚的情形,若薄厚斷差大,流速又快,則流動不穩(wěn),可能產(chǎn)生噴流。 2. 澆口非沖擊型沖擊型澆口將進(jìn)澆的熔膠導(dǎo)向一金屬面,以釋除應(yīng)力,可穩(wěn)定塑流,避免噴流。 重疊式澆口(overlap gate)和潛伏式澆口(submarine gate)即沖擊型澆口之二例。噴流噴流 JettingOLE Technology Corporation使用重疊澆口以避免噴流使用重疊澆口以避免噴流Avoid Jetting by Using Overlap Gate差的Poor好的GoodOLE Technology Corporation重疊式澆口設(shè)計(jì)重疊式澆口設(shè)計(jì)Overlap

21、Gate DesignW= w= 澆口寬度 mm gate width in mmA= 型腔表面積 mm surface area of cavity in mmn= 材料常數(shù) material constant 0.6 for PE, PS 0.7 for POM, PP 0.75 for ABS 0.8 for CA, PMMA, PA , PC 0.9 for PVC澆口厚度 gate thick. in mm = nt澆口長度 land length in mm t= 零件壁厚 wall thick. in mm 2 230n L1 = 0.50.75L2 = h+( w/2 )OLE

22、 Technology Corporation潛伏式澆口設(shè)計(jì)潛伏式澆口設(shè)計(jì)Subgate DesignW= w= 澆口寬度 mm gate width in mmA= 型腔表面積 mm surface area of cavity in mmn= 材料常數(shù) material constant 0.6 for PE, PS 0.7 for POM, PP 0.75 for ABS 0.8 for CA, PMMA, PA , PC 0.9 for PVC澆口厚度 gate thick. in mm = ntt= 零件壁厚 wall thick. in mm 30n 230 15 25 2OLE

23、Technology Corporation3. 澆口至型腔,斷面積突然變大澆口至型腔,斷面積突然變大時(shí),塑流不穩(wěn),容易產(chǎn)生噴流。澆口至型腔,斷面積應(yīng)逐漸變化,如突耳(tab)澆口或是扇形(fan)澆口, 塑流得以平穩(wěn)過渡,噴流得以避免。模模 具具噴流噴流 JettingOLE Technology Corporation充填時(shí)間短時(shí)會產(chǎn)生噴流痕和銀線充填時(shí)間短時(shí)會產(chǎn)生噴流痕和銀線Jetting Mark and Silver Streak due to Short Fill Time凸片澆口厚度為 1.5 mm側(cè)壁厚度為 3 mmPCOLE Technology Corporation幫浦零

24、件(Part, Pump)塑料(Polymer): POM進(jìn)澆處(Polymer entrance): 澆口厚(Gate thickness) 1.2mm,模穴厚(Cavity thickness) 3.2mm問題 (Problem): 噴流(Jetting)OLE Technology Corporation氣輔成型冰箱把手氣輔成型冰箱把手澆口及氣針入口澆口太小,導(dǎo)致噴流痕產(chǎn)生厚度差異過大,導(dǎo)致二次噴流痕產(chǎn)生R角過小,氣體通路接近把手內(nèi)側(cè),外側(cè)則因體積收縮造成凹陷痕跡OLE Technology Corporation凸耳澆口設(shè)計(jì)凸耳澆口設(shè)計(jì)Tab Gate DesignL= 0.50.75

25、mmW= w= 澆口寬度 mm gate width in mmA= 型腔表面積 mm surface area of cavity in mmn= 材料常數(shù) material constant 0.6 for PE, PS 0.7 for POM, PP 0.75 for ABS 0.8 for CA, PMMA, PA , PC 0.9 for PVC澆口厚度 gate thick. in mm t= 零件壁厚 wall thick. in mm 2 2 30nh1 = n th2 = 0.9 tOLE Technology Corporation扇形澆口設(shè)計(jì)扇形澆口設(shè)計(jì)Fan Gate

26、DesignL= 1.3mmW= w= 澆口寬度 mm gate width in mmA= 型腔表面積 mm surface area of cavity in mmn= 材料常數(shù) material constant 0.6 for PE, PS 0.7 for POM, PP 0.75 for ABS 0.8 for CA, PMMA, PA , PC 0.9 for PVC澆口厚度 gate thick. in mmt= 零件壁厚 wall thick. in mm 2 2 30n h1 = n t h2 = wh1/DOLE Technology CorporationOLE Tech

27、nology CorporationOLE Technology CorporationOLE Technology CorporationOLE Technology Corporation手機(jī)前殼問題點(diǎn)手機(jī)前殼問題點(diǎn)AA處印刷薄膜片在充填過程中遭沖蝕 PC公稱厚度:1.4 mm澆口厚度:0.6 mmOLE Technology Corporation波前推進(jìn)圖波前推進(jìn)圖( (原始設(shè)計(jì)一原始設(shè)計(jì)一) ) Melt Front Advancement , Original Design 1OLE Technology Corporation澆口剪切應(yīng)力澆口剪切應(yīng)力, , 原始設(shè)計(jì)一原始設(shè)計(jì)一

28、Shear Stress at Gate, Original Design 1OLE Technology Corporation澆口剪切速率澆口剪切速率, , 原始設(shè)計(jì)一原始設(shè)計(jì)一 Shear Rate at Gate, Original Design 1OLE Technology Corporation波前推進(jìn)圖波前推進(jìn)圖( (原始設(shè)計(jì)二原始設(shè)計(jì)二) ) Melt Front Advancement , Original Design 2OLE Technology Corporation澆口剪切應(yīng)力澆口剪切應(yīng)力, , 原始設(shè)計(jì)二原始設(shè)計(jì)二 Shear Stress at Gate, O

29、riginal Design 2OLE Technology Corporation澆口剪切速率澆口剪切速率, ,原始設(shè)計(jì)二原始設(shè)計(jì)二 Shear Rate at Gate, Original Design 2OLE Technology Corporation討論討論 澆口數(shù)目及流動平衡的影響澆口數(shù)目的多寡,與充填時(shí)每個(gè)澆口必須負(fù)擔(dān)的塑膠量有關(guān)。澆口數(shù)目越少,單位時(shí)間內(nèi)每個(gè)澆口必須通過的塑膠量也就越多,塑膠的前進(jìn)速度也就越快。為了避免流動過快的塑膠將印刷膜沖蝕,塑膠的流動速度必須降低, 澆口數(shù)目不能太少另外。 多澆口進(jìn)澆時(shí),必須考慮到塑流平衡的問題。當(dāng)流動不平衡時(shí),每個(gè)澆口通過的塑膠量不一。

30、如果大部分的塑膠都是通過某一特定澆口進(jìn)入模穴,可能導(dǎo)致該澆口附近的塑膠膜被充填塑膠沖蝕。OLE Technology CorporationOLE Technology CorporationOLE Technology Corporation波前推進(jìn)圖波前推進(jìn)圖( (修正設(shè)計(jì)二修正設(shè)計(jì)二) ) Melt Front Advancement , Revised DesignOLE Technology Corporation澆口剪切應(yīng)力澆口剪切應(yīng)力, , 修正設(shè)計(jì)修正設(shè)計(jì) Shear Stress at Gate, Revised DesignOLE Technology Corporatio

31、n澆口剪切速率澆口剪切速率, ,修正設(shè)計(jì)修正設(shè)計(jì) Shear Rate at Gate, Revised DesignOLE Technology Corporation結(jié)論結(jié)論改成扇形澆口並將厚度自0.6mm加厚至 0.8mm,可以使A處剪切速率降低至 4000 1/s,剪切應(yīng)力降低至 1.2 MPa,都比原始設(shè)計(jì)來得低,可以避免印刷薄膜因剪切速率及剪切應(yīng)力過高造成的沖蝕。OLE Technology Corporation使用適當(dāng)?shù)臐部谛螤钜员苊鈬娏魇褂眠m當(dāng)?shù)臐部谛螤钜员苊鈬娏鰽void Jetting by Profiling Gate Properly差的Poor好的GoodOLE T

32、echnology Corporation短射短射 Short Shot 短射(Short Shot)的定義:塑料未能充滿整個(gè)型腔 OLE Technology Corporation模模 具具 1. 模溫太低模溫太低會使得熔膠波前在型腔尚未填滿前,即已過冷不前,造成短射。提高模溫,減少短射機(jī)率。模溫可從材料廠商的建議值開始設(shè)定。 每次調(diào)整的增量可為6C,射膠10次,成型情況穩(wěn)定後,根據(jù)結(jié)果,決定是否進(jìn)一步調(diào)整。CAE模擬可以驗(yàn)證不同模溫的適用性。短射短射 Short Shot OLE Technology Corporation模模 具具 2. 澆道(Sprue)、流道(Runner)或/和

33、澆口(Gate)太小澆道、流道或/和澆口太小,流阻提高,如果射壓不足,熔膠波前的推進(jìn)會愈來愈慢,在型腔尚未填滿前,即因波前固化而造成短射。以CAE在電腦上對不同的熔膠傳送系統(tǒng)(包括噴嘴、澆道、流道和澆口)的充填進(jìn)行模擬分析,找出理想的噴嘴、澆道、流道和澆口的尺寸(包括長度和斷面有關(guān)尺寸如直徑等),是可行之道。 短射短射 Short Shot OLE Technology Corporation模模 具具 3. 澆口(Gate) 的數(shù)目或位置不當(dāng)無論澆口的數(shù)目或位置不當(dāng),都會使得流長(Flow Length) 太長,流阻太大。 如果射壓不足,熔膠波前的推進(jìn)會愈來愈慢,在型腔尚未填滿前,即因波前固

34、化而造成短射。以CAE在電腦上對不同的澆口設(shè)計(jì)進(jìn)行模擬分析,找出澆口的最佳數(shù)目和位置是聰明的作法。 4. 冷料井(Cold Slug Well) 未設(shè)或設(shè)計(jì)不當(dāng)澆道和每一段流道末端應(yīng)加冷料井。 冷料井的尺寸要恰當(dāng),上游不可有阻擋物(如拔料銷) ,才不會影響其捕捉冷料的功能。 否則任一未捕捉的冷料順流而下,都有可能堵塞澆口或小的流道,而造成短射。 短射短射 Short Shot OLE Technology Corporation冷料井設(shè)計(jì)冷料井設(shè)計(jì)Cold Slug Well Design2d次流道Secondary runnerd主流道Primary runner澆口Gate型腔Cavity

35、OLE Technology Corporation冷料井設(shè)計(jì)冷料井設(shè)計(jì)Cold Slug Well DesignOLE Technology Corporation倒椎度冷料井豎澆道拉料桿Reverse taper cold slug-well sprue pullerZ型冷料井豎澆道拉料桿 Z - taper cold slug-well sprue puller溝型冷料井豎澆道拉料桿Grooved cold slug-well sprue puller冷料井設(shè)計(jì)冷料井設(shè)計(jì)Cold Slug Well DesignOLE Technology Corporation模模 具具 5. 排氣(

36、Venting) 不足排氣不良,會使得熔膠充填受阻,甚至產(chǎn)生短射。在每一段流道末端考慮排氣,避免流道內(nèi)的氣體進(jìn)入型腔。型腔排氣更不能輕忽。 澆口對面的分模面上,考慮加排氣孔,對應(yīng)於製品盲孔末端處,考慮加排氣頂出銷。CAE模擬熔膠充填,可以幫我們很快的找到所有可能的最後充填處(Last Filled Area),也就是須要加排氣孔的地方。 按圖索驥,萬無一失。加裝抽真空系統(tǒng),在充填前和充填時(shí)進(jìn)行抽氣,是一有效方法。 對於某些咬花裝飾製品而言,這可能是唯一的排氣良方。 短射短射 Short Shot OLE Technology CorporationOLE Technology Corporat

37、ionSink marks near ribsOLE Technology Corporation凹陷或空洞凹陷或空洞Sink Mark or Void凹陷(Sink Mark)的定義:成型品表面的局部塌陷(或呈酒窩狀或呈溝壑狀)空洞(Void)的定義:成型品內(nèi)部的空洞OLE Technology Corporation氣泡或氣泡或/和凹陷的形成和凹陷的形成Void or/and Sink Mark Forming空洞空洞 ( Void )凹陷凹陷 ( Sink Mark )OLE Technology Corporation模模 具具1. 和肋相對的模面溫度太高(易形成凹陷)和肋相對的模面溫

38、度若較其附近高(一般的確如此,因?yàn)楦浇勰z集中,熱負(fù)荷大,模溫居高不下),該處凝結(jié)層薄,剛性不夠,中央的熔膠固化時(shí),有可能將較薄的凝結(jié)層向內(nèi)拉成凹陷。和肋相對的模面須加強(qiáng)冷卻,降低該處模溫,使得凝結(jié)層較快形成,當(dāng)凝結(jié)層較厚時(shí),剛性較大,凹陷不易產(chǎn)生。 模溫設(shè)定時(shí)可從材料廠商的建議值開始設(shè)定。 每次調(diào)整的減量(或增量)可為6 C,射膠10次,成型情況穩(wěn)定後,根據(jù)結(jié)果,決定是否進(jìn)一步調(diào)整。CAE可以藉凹陷指數(shù)(Sink Index) 的預(yù)測,瞭解不同冷卻設(shè)計(jì)和模溫對凹陷的影響。凹陷或空洞凹陷或空洞Sink Mark or VoidOLE Technology Corporation凹陷指數(shù)凹陷指數(shù)

39、 ( (原始設(shè)計(jì)原始設(shè)計(jì)) )OLE Technology Corporation凹陷指數(shù)凹陷指數(shù) ( (修正設(shè)計(jì)修正設(shè)計(jì)) )OLE Technology Corporation 模模 具具 2. 澆道(Sprue)、流道(Runner)或/和澆口(Gate)太小澆道、流道或/和澆口太小,流阻提高,如果射壓不足,型腔無法填實(shí),熔膠密度小,發(fā)生凹陷或空洞的機(jī)率大。以CAE在電腦上對不同的熔膠傳送系統(tǒng)(包括澆道、流道和澆口)的充填進(jìn)行模擬分析,找出理想的澆道、流道和澆口的尺寸(包括長度和斷面有關(guān)尺寸如直徑等),是可行之道。凹陷或空洞凹陷或空洞Sink Mark or VoidOLE Techno

40、logy Corporation模模 具具3. 澆口(Gate) 的數(shù)目或位置不當(dāng)無論澆口的數(shù)目或位置不當(dāng),都會使得流長(Flow Length) 太長,流阻太大。如果射壓不足,型腔無法填實(shí),熔膠密度小,發(fā)生凹陷或空洞的機(jī)率大。澆口應(yīng)儘可能置於壁厚處,確保補(bǔ)充流(Compensation Flow)的充份供應(yīng),減少凹陷或空洞的可能。 以CAE在電腦上對不同的澆口設(shè)計(jì)進(jìn)行模擬分析,找出澆口的最佳數(shù)目和位置是聰明的作法。凹陷或空洞凹陷或空洞Sink Mark or VoidOLE Technology Corporation4模穴按鍵模穴按鍵/支架模支架模4 Cavity Key/Frame Mo

41、ldOLE Technology Corporation按鍵按鍵/支架支架 Key/FrameOLE Technology CorporationSink Index DistributionOriginal (4 Gate) DesignRevised (6 Gate) DesignRevised (6 Gate/Thinner Inner Bar) DesignNote: The Inner Bar is thinned from 1.5 mm to 1 mm.OLE Technology CorporationE4057E5679E5583E6404E5540凹陷指數(shù)取值單元凹陷指數(shù)取值

42、單元 Elements from Where Sink Index are TakenOLE Technology Corporation 原始四澆口設(shè)計(jì)六澆口設(shè)計(jì)六澆口/厚壁打薄設(shè)計(jì)E40571.0490.9680E55402.1062.4702.810E55831.0641.3840E56791.0191.2540E64041.0541.0650凹陷指數(shù)比較凹陷指數(shù)比較 Sink Index ComparisonOLE Technology Corporation翹曲(Warpage)的定義: 製品頂出後不規(guī)則的尺寸變化裂痕(Cracking)的定義: 製品開裂。翹曲翹曲/裂紋裂紋Warp

43、age/CrackingOLE Technology Corporation模模 具具1. 動、靜模溫差 (Temperature Difference between Core and Cavity Mold Surfaces)大。 動靜模溫差大,因冷卻產(chǎn)生的殘餘應(yīng)力對壁厚的中心面不對稱,彎曲力矩(Bending Moment)大,容易翹曲,甚至開裂。 更改冷卻設(shè)計(jì),減少動、靜模溫差,可以減少翹曲或開裂。 CAE模擬,可以幫助找出動、靜模溫差最小的冷卻設(shè)計(jì)。翹曲翹曲/裂紋裂紋Warpage/CrackingOLE Technology Corporation原始設(shè)計(jì)原始設(shè)計(jì)Original

44、DesignOLE Technology Corporation修正設(shè)計(jì)修正設(shè)計(jì)Revised DesignAASEC. A-AOLE Technology Corporation差的設(shè)計(jì)差的設(shè)計(jì)Poor DesignOLE Technology Corporation好的設(shè)計(jì)好的設(shè)計(jì)Better DesignOLE Technology Corporation蓋子冷卻蓋子冷卻 Cap CoolingOLE Technology Corporation模模 具具2. 模溫太低模溫太低,殘餘剪切應(yīng)力大,又沒有足夠的時(shí)間將殘餘應(yīng)力釋放(Stress Release),容易翹曲,甚至開裂。提高模溫,

45、可以減少開裂。模溫可從材料廠商的建議值開始設(shè)定。 每次調(diào)整的增量可為6C,射膠10次,成型情況穩(wěn)定後,根據(jù)結(jié)果,決定是否進(jìn)一步調(diào)整。CAE模擬可以驗(yàn)證不同模溫的適切性。 翹曲翹曲/裂紋裂紋Warpage/CrackingOLE Technology Corporation模模 具具3. 澆口(Gate) 的數(shù)目或位置不當(dāng)無論澆口的數(shù)目或位置不當(dāng),都會使得流長(Flow Length) 太長。 流阻太大、相應(yīng)的射壓也須提高,塑膠分子被拉伸(Stretch)、壓擠(Squeeze),機(jī)械應(yīng)力(Mechanical Stresses)強(qiáng)行加入,殘餘應(yīng)力大,容易翹曲,甚至開裂。 澆口附近壓力高,塑膠體

46、積收縮率小,最後充填(Last Fill)處壓力低,塑膠體積收縮率大,流長太長時(shí),上下游塑膠體積收縮率差異大,殘餘應(yīng)力大,容易翹曲,甚至開裂。翹曲翹曲/裂紋裂紋Warpage/CrackingOLE Technology Corporation模模 具具3. 澆口(Gate) 的數(shù)目或位置不當(dāng)參考材料廠商的建議,採用適當(dāng)?shù)牧鏖L對厚度比(Flow Length to Thickness Ratio)。 澆口位置的決定,要遵循充填均衡(Flow Balance)的原則;即各熔膠波前到達(dá)型腔末端和形成熔接線的時(shí)間基本一致。充填應(yīng)先厚後薄、先平後彎。 進(jìn)澆應(yīng)讓熔膠遭遇立即的阻擋以避免噴流(Jettin

47、g)。 這樣可以降低殘餘應(yīng)力,減少翹曲,甚至開裂。以CAE在電腦上對不同的澆口設(shè)計(jì)進(jìn)行模擬分析,找出澆口的最佳數(shù)目和位置是聰明的作法。翹曲翹曲/裂紋裂紋Warpage/CrackingOLE Technology Corporation充填均衡充填均衡Flow Balance熔膠波前於同一時(shí)間抵達(dá)型腔各末端。Melt front reaches the ends of cavity at the same time.OLE Technology Corporation洗衣機(jī)圈板洗衣機(jī)圈板OLE Technology Corporation洗衣機(jī)圈板洗衣機(jī)圈板OLE Technology Cor

48、poration原始設(shè)計(jì)Original Design十二澆口設(shè)計(jì)十二澆口設(shè)計(jì)12 Gate Design電子零件置物箱材料 Material:ABSOLE Technology Corporation電子零件置物箱四澆口電子零件置物箱四澆口和十二澆口設(shè)計(jì)比較表和十二澆口設(shè)計(jì)比較表原始設(shè)計(jì)修正設(shè)計(jì)澆口數(shù)目124充填時(shí)間 (s)22最大射壓 (MPa)58.461.8鎖模力需求 (Ton)950820產(chǎn)品重量 (g)41364136流道系統(tǒng)重量 (g)29498OLE Technology Corporation模模 具具4. 澆道(Sprue)、流道(Runner)或/和澆口(Gate)位置

49、不當(dāng)或/和太小或/和太長澆道、流道或/和澆口位置不當(dāng)時(shí),熔接線會在強(qiáng)度敏感處產(chǎn)生,熔接線本來就弱,應(yīng)力又大,裂紋往往從熔接線開始。澆道、流道或/和澆口太小或/和太長,流阻提高,射壓也須相應(yīng)提高,塑膠分子被拉伸(Stretch)、壓擠(Squeeze),機(jī)械應(yīng)力(Mechanical Stresses)強(qiáng)行加入,殘餘應(yīng)力大,容易翹曲,甚至開裂。以CAE在電腦上對不同的熔膠傳送系統(tǒng)(包括澆道、流道、澆口和型腔)的充填、保壓、冷卻和收縮彎翹進(jìn)行模擬分析,找出並選擇翹曲(開裂可能)最小的設(shè)計(jì)是有效的作法。 翹曲翹曲/裂紋裂紋Warpage/CrackingOLE Technology Corporat

50、ion整合性收縮翹曲分析整合性收縮翹曲分析Integrated Shrinkage & Warpage Analysis總收縮變形總收縮變形 Process Induced Shrinkage & Warpage (Total Shrinkage & Warpage)不均衡冷卻 unbalanced cooling不均勻收縮 non-uniform shrinkageOLE Technology Corporation不均勻收縮不均勻收縮 Non-Uniform Shrinkage流長/壁厚比是否降低?Shall flow length/thickness ratio

51、smaller ?流動是否更平衡?Can flow be more balanced ?檢查充填系統(tǒng) Check Filling System模穴厚度和形狀、澆口數(shù)目和位置、流道尺寸和配置以及融膠溫度、射壓和充填時(shí)間Cavity thickness & shape, gate number & location, runner size & layout and melt temperature, pressure & fill timeOLE Technology Corporation壓力分佈壓力分佈 ( (原始設(shè)計(jì)原始設(shè)計(jì)) ) Pressure ( Or

52、iginal ) Max entrance pressure: 50.6 MPa Clamp force : 165.6 tonOLE Technology Corporation翹曲變形翹曲變形 (原始設(shè)計(jì)原始設(shè)計(jì)) Shrinkage & Warpage (Original Design)OLE Technology Corporation Max entrance pressure: 43.8 MPa Clamp force : 111.6 ton壓力分佈壓力分佈 (修正設(shè)計(jì)修正設(shè)計(jì))Pressure (Revised)OLE Technology Corporation 找出變

53、形的主要因素:不平衡冷卻或不均勻收縮 不均勻收縮 Find out the major cause of warpage: unbalanced cooling or non-uniform shrinkage non-uniform shrinkage 增加澆口、縮短流長,以減少不均勻收縮 變形減少 (5.1mm - 1.4mm) Add more gates and reduce flow length in order to reduce shrinkage difference reduce warpage (5.1mm - 1.4 mm)OLE Technology Corporat

54、ion不均衡冷卻不均衡冷卻 Unbalanced Cooling冷卻孔道是否均衡的配置在模穴的周圍 ? Are cooling channels erenly laid out around cavities ?是否可以採用任何冷卻單元/裝置以消除熱點(diǎn) ?Can any cooling elements/devices be used to eliminate hot spots ?冷卻液流動是否平衡 ?Shall the coolant flow more balanced ?檢查檢查冷卻冷卻系統(tǒng)系統(tǒng) Check Cooling System冷卻孔道的尺寸、配置和串聯(lián)以及冷卻迴路的溫度和流率

55、 Size, layout & circuiting of channels and temperature & flow rate of coolantOLE Technology Corporation錄影帶盒錄影帶盒Video Tape Cassette CaseOLE Technology Corporation原始設(shè)計(jì)的收縮翹曲結(jié)果原始設(shè)計(jì)的收縮翹曲結(jié)果Shrinkage & Warpage, Original Design 不均勻收縮 non-uniform shrinkage 總 process-inducedOLE Technology Corporat

56、ion 不均衡冷卻 unbalanced cooling原始設(shè)計(jì)的收縮翹曲結(jié)果原始設(shè)計(jì)的收縮翹曲結(jié)果Shrinkage & Warpage, Original Design 總 process-inducedOLE Technology Corporation冷卻水道設(shè)計(jì)冷卻水道設(shè)計(jì)-公模部份公模部份Cooling Channel Design - Core Side 原始設(shè)計(jì) Original 修正設(shè)計(jì) RevisedOLE Technology Corporation冷卻水道設(shè)計(jì)冷卻水道設(shè)計(jì)-母模部份母模部份Cooling Channel Design - Cavity Side

57、原始設(shè)計(jì) Original 修正設(shè)計(jì) RevisedOLE Technology Corporation錄影帶盒的收縮翹曲錄影帶盒的收縮翹曲Shringkag & WarpageVideo Tape Cassette Case 原始設(shè)計(jì) Original 修正設(shè)計(jì) RevisedOLE Technology CorporationPC 前面板前面板PC Front Panel128 mm455 mmOLE Technology Corporation167 mmPC 前面板前面板PC Front PanelOLE Technology Corporation6.0 mmPC 前面板前面

58、板PC Front PanelOLE Technology CorporationCooling Channel Layout PC Front PanelOLE Technology Corporation產(chǎn)品公稱厚度為3.0mm,肋厚為1.0mm、 1.5mm 、1.8mm及6.0mm 。塑膠材料Chi Mei Industry ABS POLYLAC PA-757製程條件: 充填時(shí)間: 2.5秒保壓時(shí)間: 10秒冷卻時(shí)間: 30秒開模時(shí)間: 5秒問題:凹陷(6mm肋處) 、短射(1mm肋處) 及翹曲。OLE Technology Corporation1. 去除上方窗口中的流道 (以平衡

59、充填,並減少收縮的差異)2. 地側(cè)6.0mm厚肋打薄成 3.5mm (以改善壁厚均勻度)PC前面板設(shè)計(jì)更改前面板設(shè)計(jì)更改 PC Front Panel Design ChangesOLE Technology CorporationMelt-front Advancement, Short Shot 1 PC Front PanelOriginal DesignRevised DesignOLE Technology CorporationMelt-front Advancement, Short Shot 2 PC Front PanelOriginal DesignRevised Desi

60、gnOLE Technology CorporationPC前面板前面板x軸位移軸位移 (原始設(shè)計(jì)原始設(shè)計(jì))1.85 mm1.65 mmOLE Technology CorporationPC前面板前面板x軸位移軸位移 (修正設(shè)計(jì)修正設(shè)計(jì))0.84 mm0.74 mmOLE Technology Corporationx-displacement (Total Shrinkage) PC Front PanelOriginal Design:1.85-(-1.65)=3.50(mm) InwardRevised Design:0.84-(-0.74)=1.58 (mm) Inward54.86% ImprovementOLE Technology CorporationPC前面板前面板

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