可編程控制器顯示燈外殼的注塑模具設(shè)計(jì)-抽芯注射模含11張CAD圖
可編程控制器顯示燈外殼的注塑模具設(shè)計(jì)-抽芯注射模含11張CAD圖,可編程控制器,顯示,外殼,注塑,模具設(shè)計(jì),注射,11,十一,cad
XXXXXXX
XXX設(shè)計(jì)(XXX)中期報(bào)告
題目:可編程控制器顯示燈外殼的模具設(shè)計(jì)
系 別:
專 業(yè):
班 級:
姓 名:
學(xué) 號:
導(dǎo) 師:
20XX年03月12日
4
設(shè)計(jì)(論文)中期報(bào)告
1.設(shè)計(jì)(論文)進(jìn)展?fàn)顩r
一.英文文獻(xiàn)翻譯的完成
二.對塑料所用材料進(jìn)行選擇,選用ABS工程塑料然后對塑件分形成型進(jìn)行工藝分析,接下來進(jìn)行有關(guān)工藝計(jì)算,如材料收縮率、脫模斜度、塑料件的尺寸精度等。根據(jù)計(jì)算結(jié)果確定模具類型并設(shè)計(jì)模具的內(nèi)部結(jié)構(gòu)。
三.根據(jù)塑件質(zhì)量大小選擇注塑機(jī)類型,對注塑機(jī)的主要工藝參數(shù)、安裝尺寸、開模行程和頂出裝置進(jìn)行校核。
四.澆口類型為側(cè)澆口采用自動(dòng)脫澆口;
五.模具的型腔數(shù)為一模兩腔左右布置。
六.設(shè)計(jì)、側(cè)向分型和抽芯機(jī)構(gòu)、采用常用的斜導(dǎo)柱式。
七.推出脫模機(jī)構(gòu)設(shè)計(jì)、采用頂桿推出機(jī)構(gòu)分布為八個(gè)。
八.繪制出裝配草圖
3.存在問題及解決措施
模具設(shè)計(jì)中涉及到的問題有四個(gè)澆口系統(tǒng),抽芯機(jī)構(gòu),頂出機(jī)構(gòu)和冷卻系統(tǒng)。
1、 澆注系統(tǒng):直澆口、側(cè)澆口和潛伏式澆口三種。
2、 抽芯機(jī)構(gòu):斜導(dǎo)柱側(cè)滑塊機(jī)構(gòu)、彎銷機(jī)構(gòu)和側(cè)滑塊機(jī)構(gòu),其中這三種方案里面可分為兩種,一種是四個(gè)側(cè)滑塊四個(gè)型芯,另一種是兩個(gè)側(cè)滑塊四個(gè)型芯共六種。
3、 頂出機(jī)構(gòu):頂桿頂出、頂塊頂出、頂桿加頂塊頂出三種。
4、 冷卻系統(tǒng):內(nèi)冷卻、外冷卻、內(nèi)外混合冷卻三種。
方案一:直澆口+ 斜導(dǎo)柱側(cè)滑塊機(jī)構(gòu) (四個(gè)側(cè)滑塊四個(gè)型芯)+頂桿頂出+內(nèi)冷卻。
方案二:潛伏式澆口 +彎銷機(jī)構(gòu)(兩個(gè)側(cè)滑塊四個(gè)型芯)+頂塊加頂塊頂出+內(nèi)外混合冷卻。
方案三:側(cè)澆口+斜導(dǎo)柱側(cè)滑塊機(jī)構(gòu)(兩個(gè)側(cè)滑塊四個(gè)型芯)+頂桿頂出+外冷卻。
方案一的優(yōu)點(diǎn):體積小,結(jié)構(gòu)簡單,澆口道短;缺點(diǎn):會(huì)在零件外觀上留下較大痕跡,在設(shè)計(jì)斜導(dǎo)柱時(shí)需要斜導(dǎo)柱有一定的剛度,零件上的四個(gè)方孔的位置度誤差較大,成本較高。
方案二的優(yōu)點(diǎn):表面無澆注痕跡,容易去除澆道凝料,結(jié)構(gòu)簡單,便于制造和裝配,四個(gè)方孔的位置精度高;缺點(diǎn):澆口道較長,成本較高。
方案三的優(yōu)點(diǎn):體積小,結(jié)構(gòu)簡單便于制造和裝配,四個(gè)方孔的位置精度高,不會(huì)在零件表面留下較大的痕跡;缺點(diǎn):在設(shè)計(jì)導(dǎo)柱時(shí)需要斜導(dǎo)柱有一定的剛度,頂出材料要求高。
對以上三種方案的優(yōu)缺點(diǎn)進(jìn)行比較,經(jīng)分析方案三最佳。
4.后期工作安排(按周次填寫)
進(jìn)度安排:
(1)繪制模具的完整總裝配圖和零件的仿真加工 3周
(2)編寫說明書 2周
(3)打印并交主審教師審閱 1周
5 指導(dǎo)教師意見(對課題的深度、廣度及工作量的意見)
指導(dǎo)教師: 年 月 日
6 所在系審查意見:
系主管領(lǐng)導(dǎo): 年 月 日
注:1. 正文:宋體小四號字,行距22磅。
2. 中期報(bào)告由各系集中歸檔保存。
參考文獻(xiàn)
[1] 傅水根,馬二恩,張學(xué)政.機(jī)械制造工藝基礎(chǔ).北京:清華大學(xué)出版社,1998
[2] 林建榕.機(jī)械制造基礎(chǔ).上海:上海交通大學(xué)出版社,2000
[3] 李秦蕊.塑料模具設(shè)計(jì).西安:西北工業(yè)大學(xué)出版社,2006
[4] 周四新,和青芳.Pro/Engineer Wildfire高級設(shè)計(jì).北京:機(jī)械工業(yè)出版社,2004
[5] 田緒東 管殿柱.Pro/Engineer4.0三維機(jī)械設(shè)計(jì).北京:2004機(jī)械工業(yè)出版社,2010
[6] 魏明 劉偉民.Mastercam9.0模具設(shè)計(jì)與加工. 北京:人民郵電出版社, 1993
[7] 丘宏揚(yáng),謝嘉. Pro/Engineer標(biāo)準(zhǔn)零件庫的建立.天津:模具工業(yè)出版社,2005
[8] 程培源.模具的壽命與材料.北京:機(jī)械工業(yè)出版社,1999
[9] 馬長福.實(shí)用模具技術(shù).上海:上??茖W(xué)技術(shù)文獻(xiàn)出版社,1998
[10] 沈蓮.機(jī)械工程材料與設(shè)計(jì)選材.西安:西安交通大學(xué)出版社,1996
[11] 黃毅宏,李明輝.模具制造工藝.北京:機(jī)械工業(yè)出版社,1996
[12] 高為國.模具材料.北京:機(jī)械工業(yè)出版社,1996
[13] 廖念釗,莫雨松,李碩根等.互換性與技術(shù)測量.北京:中國計(jì)量出版社,1998
[14] Rajput R K. Elements of Mechanical Engineering.Katson Publ.House,1985
[15] Kuehnle M R. Toroidal Drive Combines Concepts.Product Engineering.1979
[16] Mechanical Drive(Reference Issue).Machine Design.52(14),1980
XXXXXX
XX設(shè)計(jì)(XX)開題報(bào)告
題目:可編程控制器顯示燈外殼的模具設(shè)計(jì)
系 別:
專 業(yè):
班 級:
姓 名:
學(xué) 號:
導(dǎo) 師:
20XX年 11月 30日
XX設(shè)計(jì)(XX)開題報(bào)告
1.畢業(yè)設(shè)計(jì)(論文)題目背景、研究意義及國內(nèi)外相關(guān)研究情況。
模具是工業(yè)生產(chǎn)的基礎(chǔ)工藝裝備。振興和發(fā)展我國的模具工業(yè),日益受到人們的重視和關(guān)注。在電子、汽車、電機(jī)、電器、儀器、儀表、家電和通訊等產(chǎn)品中,60%-80%的零部件,都要依靠模具成形。用模具生產(chǎn)制件所表現(xiàn)出來的高精度、高復(fù)雜程度、高一致性、高生產(chǎn)率和低消耗,是其他加工制造方法所不能比擬的。該課題擬通過充電器外殼塑料模具的設(shè)計(jì)可以掌握中等難度模具的設(shè)計(jì)過程。通過對一具體塑件進(jìn)行系統(tǒng)化模具設(shè)計(jì),能夠全面的了解塑料模具設(shè)計(jì)的基本原則、方法.提高自己的分析能力、理論與實(shí)際相結(jié)合和自學(xué)能力。并能較為熟練的使用AUTOCAD軟件進(jìn)行塑料模具設(shè)計(jì),提高自己的繪圖能力,可以使大學(xué)四年所學(xué)知識得到綜合應(yīng)用。為今后從事設(shè)計(jì)工作打下了堅(jiān)實(shí)的基礎(chǔ)。
塑料注射模具是成型塑料的一種重要工藝裝備,在塑料制品的生產(chǎn)中起著關(guān)鍵的作用,塑料制品的應(yīng)用日漸廣泛,為塑料模具提供了一個(gè)廣闊的市場,同時(shí)對模具也提出了更高的要求。大型化、高精密度、多功能復(fù)合型的模具將會(huì)受到歡迎。用塑料模具加工的零件,具有生產(chǎn)率高、質(zhì)量好、節(jié)約材料、成本低等一系列優(yōu)點(diǎn)。因此已經(jīng)成為現(xiàn)代工業(yè)生產(chǎn)的重要手段和工藝發(fā)展方向。
近年來,工程塑料以其優(yōu)異的性能獲得了越來越廣泛的應(yīng)用。據(jù)不完全統(tǒng)計(jì),近5年來,國內(nèi)通用的聚碳酸酯、聚甲醛、聚酰胺、熱塑性聚酯、改性聚苯醚等五大工程塑料市場需求保持了30.3%的增長速度。 工程塑料在軸承上也具有廣闊的應(yīng)用前景。這是因?yàn)楣こ趟芰暇哂袃?yōu)異的自潤滑性、耐磨、低摩擦和特殊的抗咬合性等特點(diǎn),即使在潤滑條件不良的情況下也能 正常工作,用作軸承材料可謂適得其所。
2.本課題研究的主要內(nèi)容和擬采用的研究方案、研究方法或措施。
本次設(shè)計(jì)的任務(wù)是設(shè)計(jì)出一套注塑模具,通過設(shè)計(jì)能夠熟悉和掌握注塑模具的全過程,能夠根據(jù)零件的面的作用和零件的性能及特點(diǎn), 選擇適當(dāng)?shù)哪>咴O(shè)計(jì)方案。通過該設(shè)計(jì),能熟練運(yùn)用計(jì)算機(jī)進(jìn)行設(shè)計(jì)和繪圖。
研究方案:模具設(shè)計(jì)中涉及到的問題有四個(gè)澆口系統(tǒng),抽芯機(jī)構(gòu),頂出機(jī)構(gòu)和冷卻系統(tǒng)。
1、 澆注系統(tǒng):直澆口、側(cè)澆口和潛伏式澆口三種。
2、 抽芯機(jī)構(gòu):斜導(dǎo)柱側(cè)滑塊機(jī)構(gòu)、彎銷機(jī)構(gòu)和側(cè)滑塊機(jī)構(gòu),其中這三種方案里面又可分為兩種,一種是四個(gè)側(cè)滑塊四個(gè)型芯,另一種是兩個(gè)側(cè)滑塊四個(gè)型芯共六種。
3、 頂出機(jī)構(gòu):頂桿頂出、頂塊頂出、頂桿加頂塊頂出三種。
4、 冷卻系統(tǒng):內(nèi)冷卻、外冷卻、內(nèi)外混合冷卻三種。
根據(jù)排列組合總共有3×6×3×3=243種 ,現(xiàn)對其中三種進(jìn)行分析。
方案一:直澆口+ 斜導(dǎo)柱側(cè)滑塊機(jī)構(gòu) (四個(gè)側(cè)滑塊四個(gè)型芯)+頂桿頂出+內(nèi)冷卻。
方案二:側(cè)澆口 +彎銷機(jī)構(gòu)(兩個(gè)側(cè)滑塊四個(gè)型芯)+頂塊加頂塊頂出+內(nèi)外混合冷卻。
方案三:潛伏式澆口+斜導(dǎo)柱側(cè)滑塊機(jī)構(gòu)(兩個(gè)側(cè)滑塊四個(gè)型芯)+頂塊頂出+外冷卻。
方案一的優(yōu)點(diǎn):體積小,結(jié)構(gòu)簡單,澆口道短;缺點(diǎn):會(huì)在零件外觀上留下較大痕跡,在設(shè)計(jì)斜導(dǎo)柱時(shí)需要斜導(dǎo)柱有一定的剛度,零件上的四個(gè)方孔的位置度誤差較大,成本較高。
方案二的優(yōu)點(diǎn):體積小,結(jié)構(gòu)簡單,便于制造和裝配,位置精度高四個(gè)方孔的位置度誤差較?。蝗秉c(diǎn):側(cè)澆口澆口小,不易澆注,會(huì)在塑件側(cè)面形成澆注痕跡,成本較高,在設(shè)計(jì)斜導(dǎo)柱時(shí)需要斜導(dǎo)柱有一定的剛度。
方案三的優(yōu)點(diǎn):表面無澆注痕跡,容易去除澆道凝料,體積小,結(jié)構(gòu)簡單便于制造和裝配,四個(gè)方孔的位置度誤差較小,頂塊作用于分型面,不會(huì)再零件便面留下較大的痕跡,頂出時(shí)作用力較穩(wěn)定,不易損傷零件邊緣,容易脫模;缺點(diǎn):澆口較長,在設(shè)計(jì)導(dǎo)柱時(shí)需要斜導(dǎo)柱有一定的剛度,要設(shè)計(jì)頂塊,頂出材料要求高。
對以上三種方案的優(yōu)缺點(diǎn)進(jìn)行比較,經(jīng)分析方案三比較好,故選用方案三。
3.本課題研究的重點(diǎn)及難點(diǎn),前期已開展工作
通過對本次設(shè)計(jì)任務(wù)書的分析可知,本課題設(shè)計(jì)中的重點(diǎn)在于抽芯機(jī)構(gòu)的設(shè)置;設(shè)計(jì)過程的難點(diǎn)在于一模二腔的布置和設(shè)計(jì);前期已確定模具澆口系統(tǒng),抽芯機(jī)構(gòu),頂出機(jī)構(gòu)和冷卻系統(tǒng)的最佳方案和資料的查閱。
4.完成本課題的工作方案及進(jìn)度計(jì)劃(按周次填寫)
進(jìn)度安排:
(1)查閱資料 2周
(2)寫開題報(bào)告 1周
(3)模具的設(shè)計(jì)與分析 3周
(4)方案選擇與確定 3周
(5)繪制模具的裝配圖(二維和三維) 3周
(6)編寫論文 2周
(7)打印并交主審教師審閱 1周
5 指導(dǎo)教師意見(對課題的深度、廣度及工作量的意見)
指導(dǎo)教師: 年 月 日
6 所在系審查意見:
系主管領(lǐng)導(dǎo): 年 月 日
注:1. 正文:宋體小四號字,行距22磅。
2. 開題報(bào)告由各系集中歸檔保存。
5
附錄
斜滑塊NC加工代碼
N0010 G3 X13.6643 Y11.6771 I-.6403 J-1.694
N0020 G0 X12.6883 Y11.1407
N0030 X12.3908 Y10.7108
N0040 X12.2151 Y9.737
N0050 X12.6233 Y8.7633
N0060 X12.6883 Y8.6889
N0070 X13.6643 Y8.1526
N0080 X14.6404 Y8.2382
N0090 X15.3763 Y8.7633
N0100 G3 X15.7865 Y9.737 I-1.3886 J1.1582
N0110 G0 X15.7554 Y9.9076
N0120 G3 X13.8943 Y11.1945 I-1.574 J-.2871 F1250.
N0130 G0 Z-8.25
N0140 Z5.
N0150 X12.9769 Y9.9766
N0160 Z-11.25
N0170 G3 X15.7589 Y9.8047 Z-12.5 I1.3828 J-.2189 K.3751 F600.
N0180 G0 X15.7554 Y9.9076
N0190 X15.6089 Y10.7108
N0200 X14.6404 Y11.5915
N0210 G3 X13.6643 Y11.6771 I-.6403 J-1.694
N0220 G0 X12.6883 Y11.1407
N0230 X12.3908 Y10.7108
N0240 X12.2151 Y9.737
N0250 X12.6233 Y8.7633
N0260 X12.6883 Y8.6889
N0270 X13.6643 Y8.1526
N0280 X14.6404 Y8.2382
N0290 X15.3763 Y8.7633
N0300 G3 X15.7865 Y9.737 I-1.3886 J1.1582
37
N0310 G0 X15.7554 Y9.9076
N0320 G3 X13.8943 Y11.1945 I-1.574 J-.2871 F1250.
N0330 G0 Z-8.5
N0340 Z5.
N0350 X12.9769 Y9.9766
N0360 Z-11.5
N0370 G3 X15.7589 Y9.8047 Z-12.75 I1.3828 J-.2189 K.3751 F600.
N0380 G0 X15.7554 Y9.9076
N0390 X15.6089 Y10.7108
N0400 X14.6404 Y11.5915
N0410 G3 X13.6643 Y11.6771 I-.6403 J-1.694
N0420 G0 X12.6883 Y11.1407
N0430 X12.3908 Y10.7108
N0440 X12.2151 Y9.737
N0450 X12.6233 Y8.7633
N0460 X12.6883 Y8.6889
N0470 X13.6643 Y8.1526
N0480 X14.6404 Y8.2382
N0490 X15.3763 Y8.7633
N0500 G3 X15.7865 Y9.737 I-1.3886 J1.1582
N0510 G0 X15.7554 Y9.9076
N0520 G3 X13.8943 Y11.1945 I-1.574 J-.2871 F1250.
N0530 G0 Z-8.75
N0540 Z5.
N0550 X12.9769 Y9.9766
N0560 Z-11.75
N0570 G3 X15.7589 Y9.8047 Z-13. I1.3828 J-.2189 K.3751 F600.
N0580 G0 X15.7554 Y9.9076
N0590 X15.6089 Y10.7108
N0600 X14.6404 Y11.5915
N0610 G3 X13.6643 Y11.6771 I-.6403 J-1.694
N0620 G0 X12.6883 Y11.1407
N0630 X12.3908 Y10.7108
N0640 X12.2151 Y9.737
38
N0650 X12.6233 Y8.7633
N0660 X12.6883 Y8.6889
N0670 X13.6643 Y8.1526
N0680 X14.6404 Y8.2382
N0690 X15.3763 Y8.7633
N0700 G3 X15.7865 Y9.737 I-1.3886 J1.1582
N0710 G0 X15.7554 Y9.9076
N0720 G3 X13.8943 Y11.1945 I-1.574 J-.2871 F1250.
N0730 G0 Z-9.
N0740 Z5.
N0750 X12.9769 Y9.9766
N0760 Z-12.
N0770 G3 X15.7589 Y9.8047 Z-13.25 I1.3828 J-.2189 K.3751 F600.
N0780 G0 X15.7554 Y9.9076
N0790 X15.6089 Y10.7108
N0800 X14.6404 Y11.5915
N0810 G3 X13.6643 Y11.6771 I-.6403 J-1.694
N0820 G0 X12.6883 Y11.1407
N0830 X12.3908 Y10.7108
N0840 X12.2151 Y9.737
N0850 X12.6233 Y8.7633
N0860 X12.6883 Y8.6889
N0870 X13.6643 Y8.1526
N0880 X14.6404 Y8.2382
N0890 X15.3763 Y8.7633
N0900 G3 X15.7865 Y9.737 I-1.3886 J1.1582
N0910 G0 X15.7554 Y9.9076
N0920 G3 X13.8943 Y11.1945 I-1.574 J-.2871 F1250.
N0930 G0 Z-9.25
N0940 Z5.
N0950 X12.9769 Y9.9766
N0960 Z-12.25
N0970 G3 X15.7589 Y9.8047 Z-13.5 I1.3828 J-.2189 K.3751 F600.
N0980 G0 X15.7554 Y9.9076
39
N0990 X15.6089 Y10.7108
N1000 X14.6404 Y11.5915
N1010 G3 X13.6643 Y11.6771 I-.6403 J-1.694
N1020 G0 X12.6883 Y11.1407
N1030 X12.3908 Y10.7108
N1040 X12.2151 Y9.737
N1050 X12.6233 Y8.7633
N1060 X12.6883 Y8.6889
N1070 X13.6643 Y8.1526
N1080 X14.6404 Y8.2382
N1090 X15.3763 Y8.7633
N1100 G3 X15.7865 Y9.737 I-1.3886 J1.1582
N1110 G0 X15.7554 Y9.9076
N1120 G3 X13.8943 Y11.1945 I-1.574 J-.2871 F1250.
N1130 G0 Z-9.5
N1140 Z5.
N1150 X12.9769 Y9.9766
N1160 Z-12.5
N1170 G3 X15.7589 Y9.8047 Z-13.75 I1.3828 J-.2189 K.3751 F600.
N1180 G0 X15.7554 Y9.9076
N1190 X15.6089 Y10.7108
N1200 X14.6404 Y11.5915
N1210 G3 X13.6643 Y11.6771 I-.6403 J-1.694
N1220 G0 X12.6883 Y11.1407
N1230 X12.3908 Y10.7108
N1240 X12.2151 Y9.737
N1250 X12.6233 Y8.7633
N1260 X12.6883 Y8.6889
N1270 X13.6643 Y8.1526
N1280 X14.6404 Y8.2382
N1290 X15.3763 Y8.7633
N1300 G3 X15.7865 Y9.737 I-1.3886 J1.1582
N1310 G0 X15.7554 Y9.9076
N1320 G3 X13.8943 Y11.1945 I-1.574 J-.2871 F1250.
40
N1330 G3 X15.7589 Y9.8047 Z-20. I1.3828 J-.2189 K.3751 F600.
N1340 G0 X15.7554 Y9.9076
N1350 X15.6089 Y10.7108
N1360 X14.6404 Y11.5915
N1370 G3 X13.6643 Y11.6771 I-.6403 J-1.694
N1380 G0 X12.6883 Y11.1407
N1390 X12.3908 Y10.7108
N1400 X12.2151 Y9.737
N1410 X12.6233 Y8.7633
N1420 X12.6883 Y8.6889
N1430 X13.6643 Y8.1526
N1440 X14.6404 Y8.2382
N1450 X15.3763 Y8.7633
N1460 G3 X15.7865 Y9.737 I-1.3886 J1.1582
N1470 G0 X15.7554 Y9.9076
N1480 G3 X13.8943 Y11.1945 I-1.574 J-.2871 F1250.
N1490 G0 Z-16.
N1500 Z5.
N1510 M02
41
Abstract Injection moulding is one of the most versatile and important operation for mass production of plastic parts. In this process, cooling system design is very important as it largely determines the cycle time. A good cooling system design can reduce cycle time and achieve dimensional stability of the part. This paper describes a new square sectioned conformal cooling channel system for injection moulding dies. Both simulation and experimental verification have been done with these new cooling channels system. Comparative analysis has been done for an industrial part, a plastic bowel, with conventional cooling channels using the Moldflow simulation software. Experimental verification has been done for a test plastic part with mini injection moulding machine. Comparative results are presented based on temperature distribution on mould surface and cooling time or freezing time of the plastic part. The results provide a uniform temperature distribution with reduced freezing time and hence reduction in cycle time for the plastic part. Index TermsConformal cooling channel, Cycle time Moldflow, Square shape. I. INTRODUCTION Injection moulding is a widely used manufacturing process in the production of plastic parts 1. The basic principle of injection moulding is that a solid polymer is molten and injected into a cavity inside a mould which is then cooled and the part is ejected from the machine. Therefore the main phases in an injection moulding process involve filling, cooling and ejection. The cost-effectiveness of the process is mainly dependent on the time spent on the moulding cycle in which the cooling phase is the most significant step. Time spent on cooling cycle determines the rate at which parts are produced. Since, in most modern industries, time and costs are strongly linked, the longer is the time to produce parts the more are the costs. A reduction in the time spent on cooling the part would drastically increase the production rate as well as reduce costs. So it is important to understand and optimize the heat transfer process within a typical moulding process. The rate of the heat exchange between the injected plastic and the mould is a decisive factor in the economical performance of an injection mould A B M Saifullah is a research doctoral student at Industrial Research Institute Swinburne (IRIS), Swinburne University of Technology, Melbourne, Australia (e-mail- msaifullahswin.edu.au), also Member, IAENG. S. H. Masood is a Professor of Mechanical & Manufacturing Engineering at Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, Melbourne, Australia. (Corresponding author, ph:+61-3-9214 8260, fax: +61-3-9214 5050, e-mail: smasoodswin.edu.au) Dr Igor Sbarski is a Senior Lecturer at Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, Melbourne, Australia.(e-mail: isbarskiswin.edu.au ). .Heat has to be taken away from the plastic material until a stable state has been reached, which permits demolding. The time needed to accomplish this is called cooling time or freezing time of the part. Proper design of cooling system is necessary for optimum heat transfer process between the melted plastic material and the mould. Traditionally, this has been achieved by creating several straight holes inside the mould core and cavity and then forcing a cooling fluid (i.e. water) to circulate and conduct the excess heat away from the molten plastic. The methods used for producing these holes rely on the conventional machining process such as straight drilling, which is incapable of producing complicated contour-like channels or anything vaguely in 3D space. An alternative method of cooling system that conforms or fits to the shape of the cavity and core of the mould can provide better heat transfer in injection moulding process, and hence can result in optimum cycle time. This alternative method uses contour-like channels of different cross-section, constructed as close as possible to the surface of the mould to increase the heat absorption away from the molten plastic. This ensures that the part is cooled uniformly as well as more efficiently. Now-a-days, with the advent of rapid prototyping technology such as Direct Metal Deposition (DMD), Direct Metal Laser Sintering (DMLS) and many advanced computer aided engineering (CAE) software, more efficient cooling channels can be designed and manufactured in the mould with many complex layout and cross-sections2,3,4. This paper presents a square section conformal cooling channel (SSCCC) for injection moulding die. Simulation has been done for an industrial plastic part, a circular plastic bowel for these SSCCC and compared with conventional straight cooling channels (CSCC) with Moldflow Plastic Inside (MPI) software. Comparative experimental verification has also been performed with SSCCC and CSCC die for a circular shape test part with mini injection moulding machine for two plastic materials. Result shows that SSCCC die gives better cooling time and temperature distribution than that of CSCC dies. II. DESIGN OF THE PART AND MOULDS A. Part design The part circular plastic bowl made of polypropylene (PP) thermoplastic, as shown in Fig 1(a) has been designed with Pro-Engineer CAD software. It was then exported to IGES (Initial Graphics Exchange Specification) file surface model to import in MPI for analysis. Material volume of the plastic part is 177.90cm3 and its weight is 162.3 gm. Experimental test part as shown in Fig 1(b) has also been designed with Pro-Engineer software. Experimental New Cooling Channel Design for Injection Moulding A B M Saifullah, S.H. Masood and Igor Sbarski Proceedings of the World Congress on Engineering 2009 Vol I WCE 2009, July 1 - 3, 2009, London, U.K. ISBN: 978-988-17012-5-1 WCE 2009 verification has been done with two types of plastic materials, PP and ABS (Acrylonitrile Butadiene Styrene). Test part volume was 8.8 cm3, and part weight for ABS and PP were 8.68 gm and 8.13gm respectively. (a) (b) Fig-1 CAD model of (a) Circular plastic bowel, (b) Test part. B. Mould Design Mould design has been done using Pro/Moldesign module of the Pro/Engineer system. This mould is then manufactured with Computer Numerical Control (CNC) machine. The mould shown in Fig 2 has two parts, the core and the cavity. Square section conformal cooling channel (SSCCC) has been produced around the cavity by CNC machining of one half of the channel on cavity part and the other half on the core part. Both halves are then joined with screws and sealed with liquid gasket (Permatex) to avoid water leakage. Fig-2 Assembly CAD model of mould with core (top) and two cavity parts. III. ANALYSIS AND RESULTS MPI simulation software has been used for part analysis 5. Analysis sequence was flow-cool-warp. Polypropylene plastic material has been used for analysis. Comparative analysis has been done with conventional straight cooling channel (CSCC) and SSCCC. The diameter of CSCC was 12 mm and the length of SSCCC section size was 12 mm (Fig 3). Fusion meshing with global edge length of 0.995 cm has been used. The numbers of mesh elements used were 12944 and 12291 for CSCC and SSCCC respectively. (a) (b) Fig-3 Analysis setting in MPI (a) CSCC (b) SSCCC Both cases used cooling medium as normal water of 25C. Reynolds number was 10000, melting temperature was 230 C. Comparative analysis result from MPI as shown in Fig 4 shows that SSCCC shows better temperature distribution and (a) (b) Fig-4 Comparative freezing or cooling time (a) CSCC (b) SSCCC. less part freezing time than CSCC. In case of CSCC, most of the part cools in about 24 second except the top few areas, while on the other hand SSCCC diagram shows that it is less than 20 seconds. And also CSCC shows the time to freeze range to be 0.46-93.7sec and SSCCC shows this to be 0.3-87.15sec. So, using SSCCC, 5 second of cooling time has been reduced which is 35% reduction of cooling time. IV. EXPERIMENTAL VERIFICATION AND RESULTS Experimental verification has been done with a circular shape plastic test part using the machined mould as shown in Fig 5. Part diameter was 40 mm and thickness was 7 mm. The mould dimension was 10 x10 x2.5 cm3. Mould material was mild steel. Experiment has been done with a mini (a) (b) Fig-5 (a) Mild steel Core (left) and cavity with SSCCC (b) CSCC of mild steel. Proceedings of the World Congress on Engineering 2009 Vol I WCE 2009, July 1 - 3, 2009, London, U.K. ISBN: 978-988-17012-5-1 WCE 2009 injection moulding machine of TECHSOFT mini moulder (Fig 6). Two thermocouples TC08 K type of PICO technology have been used to measure temperature of top and bottom surface of the test part. Melting temperature was 250C for both ABS and PP. Normal water has been used as a cooling medium, room temperature has been measured as 25 C, so is cooling water. Cooling channel diameter was 5 mm for CSCC and SSCCC section size was 5 mm. With two thermocouples, surface temperature of the test part has been measured for every second. Fig-6 Experimental setup for test injection moulding, left: mini moulder, right: temperature output in PC. Fig 7 and Fig 8 show the comparative temperature distribution for top and bottom surface of the plastic parts for 30 second. Fig-7 Comparative temperature plot for ABS From Fig 7 it is noted that for the ABS plastic, using SSCCC, the top face and bottom face of test part cooled earlier than that with CSCC. In case of SSCCC, maximum top and bottom surface temperature recorded at particular time immediately after injection were 53.36 C and 52.1C. After 30 second, this temperature reduced to 42.47 C and 43.07 C, whereas, for CSCC they were 53.24, 52.01 and 47.47, 47.72 C. So in average, 4 to 5 C reduction in temperature happens using the SSCCC. Similar results also have been found when using PP as the part material. From Fig 8, it can be shown that using SSCCC, about 2 to 3C reduction in temperature can be possible. Fig-8 Comparative temperature plot for PP In experimental tests, twenty sample test parts have been produced for ABS and PP material for experimental verification and in every case almost the same data has been found. Fig 9 shows the sample test parts in ABS and PP, which have been produced for experimental verification. Fig-9 Sample test part produced for experimental verification Left: ABS right: PP plastic. V. CONCLUSION The cooling process is one of the most important sub processes in injection moulding because it normally accounts for approximately half of the total cycle time and affects directly the shrinkage, bending and warpage of the moulded plastic product. Therefore, designing a good cooling channel system in the mould is crucial since it influences the production rate and quality. The results of MPI simulation and experimental verification show that using square shape conformal cooling channels gives up to 35% reduction in cooling time and 20% of the total cycle time can be obtained, thus greatly improving the production rate and the production quality of injection moulded parts. ACKNOWLEDGMENT These authors are grateful to Mrs. Meredith and Phil Watson of Faculty of Engineering and Industrial Science, Swinburne University of Technology for their technical support for die making with CNC machining. Proceedings of the World Congress on Engineering 2009 Vol I WCE 2009, July 1 - 3, 2009, London, U.K. ISBN: 978-988-17012-5-1 WCE 2009 REFERENCES 1 D.V. Rosato, D.V. Rosato and M.G. Rosato, Injection Moulding Handbook-3rd ed , Boston, Kluwer Academic Publishers, (2003). 2 X. Xu, E. Sach and S.Allen, The Design of Conformal Cooling Channels In Injection Moulding Tooling,Polymer Engineering and Science, 4, 1, pp 1269-1272, (2001). 3 D.E. Dimla, M. Camilotto, and F. Miani: Design and optimization of conformal cooling channels in injection moulding tools, J. of Mater. Processing Technology, 164-165, pp 1294-1300, (2005). 4 A B M Saifullah and S. H. Masood, Optimum cooling channels design and Thermal analysis of an Injection moulded plastic part mould, Materials Science Forum, Vols. 561-565, pp. 1999-2002, (2007). 5 A B Saifullah, S. H. Masood and Igor Sbarski, cycle time optimization and part quality improvement using novel cooling channels in plastic injection moulding. ANTECNPE 2009, USA. Proceedings of the World Congress on Engineering 2009 Vol I WCE 2009, July 1 - 3, 2009, London, U.K. ISBN: 978-988-17012-5-1 WCE 2009
收藏