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畢業(yè)設(shè)計（論文）報告
題 目 奧迪汽車標志注塑模設(shè)計與制造
系 別 中德機電學(xué)院
專 業(yè) 模具設(shè)計與制造
班 級 模具0703班
姓 名 趙凱
學(xué) 號 100071506
指導(dǎo)教師 袁小江
2010年 4 月
目錄
摘要 ····························································2
前言·····························································3
第一章 材料工藝分析
1.1 材料特性···············································4
1.2 模具設(shè)計方面需注意·····································4
1.3 注塑工藝條件···········································4
1.4 成型性能···············································4
第二章 制品結(jié)構(gòu)及尺寸分析
2.1 制品結(jié)構(gòu)分析···········································5
2.2 制品尺寸精度分析·······································5
第三章 模具結(jié)構(gòu)設(shè)計
3.1 分型面的選擇···········································6
3.2 型腔布局···············································7
3.3 澆注系統(tǒng)的確定·········································8
3.4 注射機的選擇···········································12
3.5 模架的選擇·············································14
3.6 成型零部件設(shè)計·········································15
3.7 推出機構(gòu)設(shè)計···········································17
3.8 排氣系統(tǒng)設(shè)計···········································18
3.9 冷卻系統(tǒng)設(shè)計···········································19
附 畢業(yè)設(shè)計小結(jié)···········································20
謝辭···················································21
參考文獻···············································22
[摘 要]
本課題是江蘇省普通高等院校模具設(shè)計與制造專業(yè)，專題綜合實踐項目之一。是對模具專業(yè)學(xué)生的一次綜合考察。
設(shè)計者需通過課題的CAD二維工程圖紙，進行模具設(shè)計。其中包括：產(chǎn)品材料、工藝、結(jié)構(gòu)、尺寸精度分析，成型零件尺寸計算，合理選擇注塑機及標準模架。并用CAD2006完成模具總裝圖及成型零件圖的繪制，完成成型零件的加工工藝卡編寫等。
本設(shè)計主用軟件CAD2006，通過CAD2006完成相關(guān)元件的二維工程圖紙。并結(jié)合Pro/ENGINEER4.0進行輔助設(shè)計。經(jīng)過反復(fù)修改，最終完成課題設(shè)計。
關(guān)鍵詞：模具 標準模架 CAD2006
Abstract
This topic is ordinary colleges and universities in Jiangsu Province mold design and manufacturing expertise, special comprehensive practice items.Is to mold a comprehensive survey of students.
Designers have passed the two-dimensional capacitance Block CAD engineering drawings, for mold design.These include: product materials, processes, structure, size precision analysis, forming part size calculation, a reasonable choice and standard mold injection molding machine.And use CAD2006 complete the mold assembly diagram and forming part drawing of the drawing, forming part of the processing technology to complete the preparation of such cards.
The design of the main software CAD2006, with the completion of related components over CAD2006 two-dimensional engineering drawings.Carried out in conjunction with Pro/ENGINEER4.0-aided design.After repeated changes to the final completion of the design issues.
Keywords：Mold Standard Mold CAD2006
前言
模具制造是我國經(jīng)濟建設(shè)中的一項重要產(chǎn)業(yè)，起著振興和發(fā)展我國模具工業(yè)的重要作用，正日益受到人們的重視和關(guān)注?！澳＞呤枪I(yè)生產(chǎn)的基礎(chǔ)工藝裝備”也已經(jīng)成為廣大業(yè)內(nèi)人士的共識。在電子、汽車、電機、電器、儀器、儀表、家電和通信等產(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,具備高精度、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。模具又是“效益放大器”，用模具生產(chǎn)的最終產(chǎn)品的價值，往往是模具自身價值的幾十倍、上百倍,尤其是在沖壓技術(shù)相對落后的中國，制造出優(yōu)質(zhì)的模具以及生產(chǎn)出高質(zhì)量的產(chǎn)品勢在必行。
經(jīng)過本次的課題研究主要掌握模具設(shè)計的方法及工序，鞏固和加深對機械二維、三維的制圖能力。設(shè)計過程中鍛煉查閱文獻和資料、自我設(shè)計的能力，培養(yǎng)和提升自己的創(chuàng)新能力，增強獨立思考問題和解決問題的能力。在對模具設(shè)備的結(jié)構(gòu)設(shè)計和理論計算上，掌握模具設(shè)備的主要結(jié)構(gòu)與性能、工藝適應(yīng)性與技術(shù)參數(shù)。從而能根據(jù)成型的生產(chǎn)要求、模具結(jié)構(gòu)等因素，經(jīng)濟、有效的使用設(shè)備，合理的選擇工藝，正確的設(shè)計模具，保證成型生產(chǎn)能夠經(jīng)濟、合理的進行，提高自身在成型工藝和模具方面的綜合著機水平，提高自身解決實際問題的能力。
在這次畢業(yè)設(shè)計過程中，我得到了袁小江老師的指導(dǎo)，他給了我很多意見和建議，使我的設(shè)計更加完善，在此特別的感謝他。同時也感謝那些曾經(jīng)授課的老師，他們使我學(xué)習(xí)、獲得了專業(yè)知識，對設(shè)計起了重要作用。也要感謝那些幫過我的同學(xué)，他們給我提了很多好的建議。
第一章 材料工藝分析
1.1材料特性
ABS無色、無味、呈微黃色。密度為1.02~1.05g/cm3（注射注射級密度為1.05g/cm 3）。具有優(yōu)越的綜合性能：強度高、剛性好，硬度、耐沖擊性、制品表面光澤性好，耐磨性好。具有有良的成型加工性，尺寸穩(wěn)定性好，著色性能、電鍍性好。
1.2在模具設(shè)計方面需注意：
⑴需要采用較高的料溫與模溫，澆注系統(tǒng)的流動阻力要小。
⑵注意選擇澆口位置，避免澆口與熔接痕位于影響制品外觀的部位。
⑶合理設(shè)計頂出脫模結(jié)構(gòu)，推出力過大時，制品表面易“發(fā)白”、“變混”（頂白）。
1.3注塑工藝條件
干燥處理：ABS材料具有吸濕性，要求在加工之前進行干燥處理。建議干燥條件為80~90℃下最少干燥2小時。
料筒溫度：210~280℃，建議溫度：245℃。
模具溫度：40~80℃（模具溫度將影響塑件光潔度，溫度較低則導(dǎo)致光潔度較低）。
注射壓力：70~120MPa
注射速度：中高速度
1.4成型性能
ABS在升溫時粘度增高，所以成型壓力較高，故塑件上的脫模斜度宜稍大；ABS易產(chǎn)生熔接痕，模具設(shè)計時應(yīng)注意盡量減少澆注系統(tǒng)對料流的阻力；在正常的成型條件下，壁厚、熔料溫度對收縮率影響極小。在要求塑件精度高時，模具溫度可控制在50～`60℃，而在強調(diào)塑件光澤和耐熱時，模具溫度應(yīng)控制在60～`80℃。
第二章 制品結(jié)構(gòu)及尺寸分析
2.1制品結(jié)構(gòu)分析
該制品由四個相交的圓環(huán)組成，如圖所示，形狀規(guī)則；成型時外形表面質(zhì)量高，要求表面光潔，無毛刺、缺陷；制品最終要進行表面電鍍處理。
圖1
2.2制品尺寸精度分析
該制品尺寸要求較高，尺寸公差按GB/T14486-93MT4±分布，總體尺寸較小。
第三章 模具結(jié)構(gòu)設(shè)計
3.1分型面的選擇
選擇分型面應(yīng)考慮以下原則：
1)分型面應(yīng)選擇在塑件外形最大輪廓處。塑件在動、定模的方向確定后，其分型面應(yīng)選擇在塑件外形的最大輪廓處，否則塑件會無法從型腔中脫出，這是最基本的原則。
2)分型面的選擇應(yīng)有利于塑件的順利脫模。由于注射機的頂出裝置在動模一側(cè)，所以分型面的選擇應(yīng)盡可能地使塑件在開模后留在動模一側(cè)，這樣有利于在動模部分設(shè)置推出機構(gòu)。
3)分型面的選擇應(yīng)保證塑件的精度要求。對于與分型面垂直的尺寸，若該尺寸與分型面有關(guān)，由于分型面在注射成型時有漲開的趨勢，故該尺寸的精度會受到影響。分型面盡可能不設(shè)在尺寸精度要求很高的地方。
4)分型面的選擇應(yīng)滿足塑件的外觀質(zhì)量要求。在分型面處會不可避免地在塑件上留下溢流飛邊的痕跡，因此分型面最好不要開設(shè)在塑件光亮平滑的外表面或帶圓弧的轉(zhuǎn)角處，以免對塑件的外觀質(zhì)量產(chǎn)生不利的影響。
5)分型面的選擇要便于模具的加工制造。通常情況下，會選擇平直的分型面較多。但為了便于模具的制造，應(yīng)根據(jù)模具的實際情況選擇合理的分型面。
6)分型面的選擇應(yīng)有利于排氣。在設(shè)計分型面時應(yīng)盡量使充填型腔的塑料熔體料末端在分型面上，這樣有利于排氣。
分型面的選擇還要考慮到型腔在分型面上投影面積的大小，以避免接近或超過所選注射機的最大注射面積而可能產(chǎn)生溢流現(xiàn)象。
考慮以上原則，該制品的分型面應(yīng)如圖2所示，否則達不到制件的質(zhì)量要求。
圖2
3.2型腔布局
一般制品在布局時要求模具的中心與注塑機的鎖模中心重合，對于一模多件的模具結(jié)構(gòu)，在澆注系統(tǒng)分流道的流程短、模具結(jié)構(gòu)緊湊、保證模具正常工作的前提下，應(yīng)盡可能使得模具對稱、均衡、取件方便。本制品采用一模兩件，對稱分布。
按塑件外形尺寸近似計算：
單個塑件體積Vs≈4.18cm
ABS的密度為1.02～1.05g/cm3 (注射級密度為1.05g/cm3)
單件塑件重量Ms=4.18×1.05≈4.4g
3.3澆注系統(tǒng)的確定
澆注系統(tǒng)設(shè)計應(yīng)遵循以下原則：
1)了解塑料的成型性能。注射成型時注射機料筒中的塑料已成熔融狀態(tài)(粘流態(tài)），因此了解被成型的塑料熔體的流動特性以及溫度、剪切速率對粘度的影響等顯得十分重要。澆注系統(tǒng)要適應(yīng)于ABS的成型性能，以保證成型塑件的質(zhì)量。
2)盡量避免或減少產(chǎn)生熔接痕。在選擇澆口位置時，應(yīng)注意避免熔接痕的產(chǎn)生。熔體流動時應(yīng)盡量減少分流的次數(shù)。
3)有利于型腔中氣體的排除。澆注系統(tǒng)應(yīng)能順利地引導(dǎo)塑料熔體充滿型腔的各個部分，使?jié)沧⑾到y(tǒng)及型腔中原有的氣體能有序地排出，避免充填過程中產(chǎn)生紊流或渦流，也避免因氣體積存而引起凹陷、氣泡、燒焦等塑件的成型缺陷。
4)防止型芯的變形和嵌件的位移。澆注系統(tǒng)設(shè)計時應(yīng)盡量避免塑料熔體直接沖擊細小型芯和嵌件，防止熔體的沖擊力使細小變形或嵌件位移。
5)盡量采用較短的流程充填型腔。選擇合理的澆口位置，減少流道的折彎，提高流道的表面粗糙度，這樣就可以減少充填時間，避免因流程長、壓力和熱量損失大而引起的型腔充填不滿等成型缺陷。
6)流動距離比和流動面積比的校核。在模具設(shè)計過程中除了考慮采用較短的流程外，還應(yīng)對其注射成型時的流動距離比或流動面積比進行校核，這樣可以避免型腔充填不足現(xiàn)象的發(fā)生。
3.3.1澆口的形式及位置
3.3.1.1澆口的位置選擇
澆口的選擇應(yīng)注意：
1)盡量縮短流動距離
2)避免熔體破裂現(xiàn)象引起塑件的缺陷
3)澆口應(yīng)開設(shè)在塑件壁厚處
4)考慮分子定向的影響
5)減少熔接痕提高熔煉強度
3.3.1.2澆口的形式
由于該制品外表面質(zhì)量要求較高，且最后要進行電鍍處理，因此采用潛伏澆口，如圖3所示，熔料通過推桿的端部注入型腔，在環(huán)的相交處進料，因而塑件外表面不受損傷，不致因澆口痕跡而影響塑件的表面質(zhì)量與美觀效果。
澆口直徑可以根據(jù)經(jīng)驗公式計算
d=(0.14~0.2) ≈1.8mm
式中d —澆口直徑（mm）
δ—塑件在澆口處的壁厚（mm）
A—型腔表面積（mm）
潛伏澆口的錐角β取10°~20°，取12°
傾角α取30°~60°，取40°
推桿上進料口寬度為0.8~2mm, 取1mm
圖3
3.3.2初步設(shè)計主流道
主流道的形狀和尺寸對塑料的熔體的流動速度和充模時間有較大的影響。因此必須使熔體的溫度降和壓力損失最小。主流道垂直于分型面而且設(shè)計在模具的澆口套中。為了讓主流道凝料能順利從澆口套中拔出，因此主流道設(shè)計成圓錐形，其錐角為2°～6°，小端直徑d比注射機噴嘴直徑大0.5～1mm。由于小端的前面是球面，其深度為3~5mm，注射機噴嘴的球面在該位置與模具接觸并且貼合，因此要求主流道球面半徑比噴嘴球面半徑大1~2mm。主流道表面粗糙度Ra≤0.8um。
主流道錐角取4°，小端的球面深度取4mm，小端直徑d和主流道球面半徑可根據(jù)后面注射機的選擇來確定。
澆口套采用如圖4所示的形式，以銷釘和定位圈固定，澆口套與模板間的配合采用H7/m6的過渡配合，澆口套與定位圈采用H9/f9的配合。定位圈在模具安裝調(diào)試時應(yīng)插入注射機定模板的定位孔內(nèi)，用于模具與注射機的安裝定位。定位圈外徑比注射機定模板上的定位孔徑小0.2mm以下。
圖4
3.3.3初步設(shè)計分流道
3.3.3.1分流道的形狀與尺寸
在設(shè)計多型腔或多澆口的單型腔的澆注系統(tǒng)時，應(yīng)設(shè)置分流道，使熔體平穩(wěn)的均衡的分配到各型腔。設(shè)計時應(yīng)注意盡量減少流動過程中的熱量損失與壓力損失。
圖5
常用分流道截面形式有圓形、梯形、U形、半圓形及矩形，如圖5所示。圓形截面的比表面積最小，但需開設(shè)在分型面的兩側(cè)，在制造時一定要注意模板上兩部分形狀對中吻合；矩形截面分流道其比表面積較大且流動阻力也大，故不采用；相比較而言，半圓形截面分流道加工容易，且熱量損失與壓力損失均不大，且可參照圓形截面分流道。根據(jù)塑料的流動性等因素來確定分流道直徑。該制品采用ABS塑料，流動性中等，根據(jù)經(jīng)驗，分流道直徑可取5~6mm，在這里取6mm
3.3.3.2分流道的長度
根據(jù)型腔在分型面的分布情況，分流道可分為一次分流道、二次分流道甚至三次分流道。分流道的長度要盡可能的短，且折彎少，以便減少壓力損失和熱量損失，節(jié)約塑料的原材料和降低能耗。
這里只需一次分流，長度L=6~10mm,取10mm
3.3.3.3冷料穴和拉料桿的設(shè)計
冷料穴是澆注系統(tǒng)的組成結(jié)構(gòu)之一。它的作用是容納澆注系統(tǒng)流道中料流的前鋒冷料，一面這些冷料注入型腔。這些冷料既影響熔體充填的速度，又影響成型塑件的質(zhì)量。主流道末端的冷料穴除了上述作用外，還有便于在該處設(shè)置主流道拉料桿的功能。
注射結(jié)束模具分型時，在拉料桿的作用下，主流道凝料從定模澆口套中被拉出，最后推出機構(gòu)開始工作，將塑件和澆注系統(tǒng)凝料一起推出模外。這里采用推桿式Z字形拉料桿，工作時依靠Z字形鉤將主流道凝料拉出澆口套，推出后由于鉤子的方向性而不能自動脫模，需要人工取出。
3.4注射機的選擇
初選注射機
（1）注射量
該塑料制件單件重Ms≈4.4g
澆注系統(tǒng)重量可根據(jù)澆注系統(tǒng)尺寸先計算澆注系統(tǒng)的體積
Vj≈0.85㎝3
粗略計算澆注系統(tǒng)重量Mj=0.85×1.05≈0.89g
總體積V塑件 =2×4.18+0.85=9.21 cm 3
總重量M=9.21×1.05≈9.67g
滿足注射量V機≥ V塑件 /0.80
式中：V機——額定注射量(cm3)
V塑件——塑件與澆注系統(tǒng)凝料體積和(cm3)
V塑件/0.80=9.21/0.8=11.51cm 3
（2）注射壓力：
P注≥ P成型
查相關(guān)資料，ABS塑料成型時的注射壓力P成型=70-90MPa
（3）鎖模力：
P鎖 ≥PF
式中：P——塑料成型時型腔壓力，ABS塑料的型腔壓力為P=30MPa
F——澆注系統(tǒng)和塑件在分型面上的投影面積之和(mm3)
pF=30×(963+55)N=30.5kN
根據(jù)以上分析，計算查表，初選出選注射機，型號為XS-Z-30。
該型號注射機有關(guān)技術(shù)參數(shù)如下:
額定注射量 30cm3
注射壓力 119MPa
鎖模力 250KN
最大成型面積 90cm2
最大開合模行程 160mm
模具最大厚度 180mm
模具最小厚度 60mm
噴嘴圓弧半徑 12mm
噴嘴孔直徑 2mm
動定模固定板尺寸 250×280mm
拉桿空間 235mm
3.5模架的選擇
3.5.1選擇標準模架
為適應(yīng)大規(guī)模成批量生產(chǎn)塑料成型模具，提高模具精度和降低模具成本，這里選用標準模架。
根據(jù)以上分析，計算以及型腔尺寸及位置可確定模架的結(jié)構(gòu)形式和規(guī)格。查表可選用：
A2-200200-27-Z2 GB/T12556.1-1990
定模板厚度：A=25mm
動模板厚度：B=20mm
墊塊厚度：C=50mm
模具厚度H=82+25+20+50=177mm
模具外形尺寸:200mm×250mm×177mm
3.5.2 校核注射機
（1）注射量、鎖模力、注射壓力、模具厚度的校核：
由于在初選注射機和選用標準模架時是根據(jù)以上四個技術(shù)參數(shù)及計算壁厚等因素選用的，所以注射量、鎖模力、注射壓力、模具厚度不必進行校核，已符合所選注射機要求。
（2）開模行程的校核
注射機最大開模行程S
S≥H1+H2+(5～10)mm
式中H1-推出距離（脫模距離），mm
H2-包括澆注系統(tǒng)在內(nèi)的塑件高度，mm
S≥5+46+10=61mm
該型號注射機最大開模行程為160mm，故滿足要求。
（3）模具在注射機上的安裝
從標準模架外形尺寸看，小于注射機拉桿空間，并采用壓板固定，因此所選注射機規(guī)格滿足要求
3.6成型零部件的結(jié)構(gòu)設(shè)計
成型零件的結(jié)構(gòu)設(shè)計應(yīng)考慮成型零件對制品的質(zhì)量影響、成型零件的加工工藝性、裝配工藝性和制品脫模的需要。成型零件工作時，直接與塑料熔體接觸，承受熔體料流的高壓沖刷，脫模摩擦等，因此，成型零件不僅要求有正確的幾何形狀，較高的尺寸精度和較低的表面粗糙度，而且還要求有合理的結(jié)構(gòu)，較高的強度、剛度及較好的耐磨性。
3.6.1型腔的結(jié)構(gòu)設(shè)計
型腔是成型塑件外表面的主要零件。按結(jié)構(gòu)不同可分為整體式和組合式兩種結(jié)構(gòu)形式。整體式結(jié)構(gòu)是在整塊金屬模板上加工而成的。其特點是牢固，不易變形，不會是塑件產(chǎn)生拼接線痕跡。該模具尺寸不大，形狀簡單，故選擇整體式型腔結(jié)構(gòu)。
3.6.2型芯的結(jié)構(gòu)設(shè)計
型芯是成型內(nèi)表面的零件。按結(jié)構(gòu)主型芯可分為整體式和組合式兩種。整體式結(jié)構(gòu)牢固，但不便加工，消耗的模具鋼多，主要用于工藝試驗或小型模具上形狀簡單的型芯。由于該制品需要成型的型芯較多，且相聚較近，為便于加工，故采用組合式結(jié)構(gòu)，將型芯單獨加工后再鑲?cè)肽０逯?。這里采用通孔臺肩式，凸模用臺肩和模板連接，再用墊板，螺釘緊固，連接牢固。
3.6.3成型零件的工作尺寸計算
成型零部件工作尺寸是指直接用來構(gòu)成塑件型面的尺寸。如型腔和型芯的徑向尺寸、深度和高度尺寸、孔間距離尺寸。
查表得ABS塑料的收縮率是0.3～0.8%，平均收縮率：
=（0.3+0.8）/2=0.55%
型芯尺寸：
Φ240..32 lm0-δz=[(1+)lS-χΔ] 0-δz=〔1.0055×24+0.75×0.32〕0..32/3 =24.3720.107
型腔尺寸
50.38 (Hm)δz =[(1＋)LS-χΔ] +δz0 =〔1.0055×5-0.75×0.38〕0.38/3 =4.740.127
R30.16 (LM)δz =[(1＋)LS-χΔ] +δz0 =〔1.0055×3-0.75×0.16〕0.16/3 =2.8970..053
Φ300..36 (LM)δz =[(1＋)LS-χΔ] +δz0 =〔1.0055×30-0.75×0.36〕0..36/3 =29.8950.120
中心距尺寸
20±0.16 (CM)δZ/2=(1+) CSδZ/2=1.0055×20±0.32/8=20.11±0.04
3.7推出機構(gòu)的確定
3.7.1推出機構(gòu)的設(shè)計要求
(1)設(shè)計推出機構(gòu)時應(yīng)盡量使塑件留于動模一側(cè)。由于推出機構(gòu)的動作是通過注射機的動模一側(cè)的頂桿或液壓缸來驅(qū)動的，所以，在一般情況下，模具的推出機構(gòu)設(shè)在動模一側(cè)。
(2)塑件在推出過程中不發(fā)生變形和損壞。為了使塑件在推出過程中不發(fā)生變形和損壞，設(shè)計模具時應(yīng)仔細進行塑件對模具包緊力和粘附力大小的分析與計算，合理的選擇推出的方式、推出的位置、推出零件的數(shù)量和推出面積等。
(3)不損壞塑件的外觀。
(4)合模時應(yīng)使推出機構(gòu)正確復(fù)位。設(shè)計推出機構(gòu)時，應(yīng)考慮合模時推出機構(gòu)的復(fù)位，在有側(cè)型芯的機構(gòu)中，還要考慮推出機構(gòu)的先復(fù)位。
(5)推出機構(gòu)應(yīng)動作可靠。推出機構(gòu)在推出與復(fù)位的過程中，結(jié)構(gòu)應(yīng)盡量簡單，動作可靠、靈活，制造容易。
3.7.2推出力的計算
塑件注射成型后，在模內(nèi)冷卻定型，由于體積收縮，對型芯產(chǎn)生包緊力。當(dāng)其從模具中推出時，就必須克服因包緊力而產(chǎn)生的摩擦力。
推件力的計算
推出力 Ft=Ap(μcosα-sinα)
式中 A—塑件包絡(luò)型芯的面積（mm2）；
p—塑件對型芯單位面積上的包緊力，p取0.8×107～1.2×107Pa；
α—脫模斜度；
μ—塑件對鋼的摩擦系數(shù)，約為0.1～0.3；
單個塑件A≈2×3.14×12×5=376.8mm 2
Ft=376.8×1.2×107 ×0.3/106 =1356.48N
由于該塑件型腔不深，故不考慮脫模斜度。
3.7.3推出機構(gòu)的選擇
由于該制品采用潛伏澆口，且為不影響制品表面，故從推桿上端進料，因此采用推桿推出機構(gòu)。設(shè)置推桿的自由度大，而且推桿截面大部分為圓形，制造、修配方便，容易達到推桿與模板或型芯上推桿孔的配合精度，推桿推出時運動阻力小，推出動作靈活可靠，推桿損壞后也便于更換。
通過分析計算，推桿采用圓形截面，直徑取2mm，單個制件使用8根推桿。推桿工作部分與模板或型芯上的推桿孔的配合常采用H8/f7～H8/f8的間隙配合。
推桿的位置應(yīng)選擇在脫模阻力最大的地方；當(dāng)塑件各處的脫模阻力相同時需均勻布置，以保證塑件推出時受力均勻，塑件推出平穩(wěn)和不變形。
推桿的工件端面在合模注射時是型腔底面的一部分，推桿端部如果低于或高于該改型腔底面，在塑件上就會產(chǎn)生凸臺或凹痕，影響塑件的使用或美觀，因此，通常推桿裝入模具后，其端面應(yīng)與型腔底面平齊或高出型腔0.05～0.1mm。推桿工作端配合部分的粗糙度Ra一般取0.8um。
3.8排氣系統(tǒng)的設(shè)計
當(dāng)塑料熔體充填模具型腔時，必須將澆注系統(tǒng)和型腔內(nèi)的空氣及塑件在成型過程中產(chǎn)生的低分子揮發(fā)氣體順利地排出模外。如果型腔內(nèi)因各種原因產(chǎn)生的氣體不能被排除干凈，塑件上就會形成氣泡、產(chǎn)生熔接不牢、表面輪廓不清及充填不滿等成型缺陷。另外氣體的存在還會產(chǎn)生反壓力而降低充模速度。因此，必須考慮到模具型腔的排氣問題。
通常有三種排氣方式：利用配合間隙排氣、在分型面上開設(shè)排氣槽和利用排氣塞排氣。由于此模具推桿較多且有型芯鑲塊，故可利用推桿和型芯端部與模板的配合間隙進行排氣。
3.9冷卻系統(tǒng)的設(shè)計
模具溫度是否合適、均一與穩(wěn)定，對塑件熔體的充模流動、固化定型、生產(chǎn)效率及塑件的形狀、外觀和尺寸精度都有重要影響，所以要設(shè)置溫度調(diào)節(jié)系統(tǒng)來控制模具溫度，使注射成型塑件有良好的產(chǎn)品質(zhì)量和較高的生產(chǎn)效率。
3.9.1模具溫度與塑料成型溫度
注射入模具的熱塑性熔融的ABS，必須在模具內(nèi)冷卻固化才能成為塑件。所以模具溫度必須低于注射入模具型腔內(nèi)的熔融ABS的溫度。
ABS的成型溫度為200-270°C，模具溫度為40-80°C。
3.9.2冷卻回路的設(shè)計
考慮到冷卻回路的設(shè)計應(yīng)做到回路系統(tǒng)內(nèi)流動的介質(zhì)能充分吸收成型塑件所傳導(dǎo)的熱量，使模具成型表面的溫度穩(wěn)定地保持在所需的溫度范圍內(nèi)，且要使冷卻介質(zhì)在回路系統(tǒng)內(nèi)流動暢通，無滯留部位。
由于制件平均壁厚約為3mm，而且是一模兩腔，所以根據(jù)經(jīng)驗數(shù)值確定水孔直徑為10mm。
由于冷卻水道的位置、結(jié)構(gòu)形式、孔徑、表面狀態(tài)、水的流速、模具 材料等很多因素都會影響模具的熱量向冷卻水傳遞，精確計算比較困難。實際生活中，通常都是根據(jù)模具的結(jié)構(gòu)確定冷卻水路，通過調(diào)節(jié)水溫、水速來滿足要求。
由于動模采用鑲拼式，受結(jié)構(gòu)限制，冷卻水路布置定模板上面，設(shè)置四條冷卻水道，采用對稱分布。
畢業(yè)設(shè)計小結(jié)
畢業(yè)設(shè)計歷時數(shù)月，現(xiàn)已定稿。在整個設(shè)計過程中，不僅自己的專業(yè)知識得到了鞏固和提高，在查閱相關(guān)專業(yè)手冊、與同學(xué)交流意見等方面也有很多心得。
整個設(shè)計時間是漫長的，過程是困難的，我覺得如果自己真正的認真對待了這次畢業(yè)設(shè)計，就能從中學(xué)到很多東西，自己的綜合素質(zhì)也在無形中得到了提高。
起初是最困難的，因為我要從中理出一個正確的設(shè)計思路。為了做好充分準備，我查閱了很多關(guān)于模具設(shè)計方面的資料和實例。同時我又向袁老師說了我的有關(guān)想法。在他的悉心指導(dǎo)下，我的思路慢慢的清晰起來，并且有了自己獨立的想法，很快我就明確了自己的設(shè)計方向。
接下來，我對產(chǎn)品的材料、工藝性、結(jié)構(gòu)、尺寸精度等方面進行分析，并計算出成型零件的相關(guān)尺寸，選擇了合理的注塑機及標準模架，再對模具結(jié)構(gòu)進行系統(tǒng)設(shè)計。在整個設(shè)計中，最重要的是有關(guān)型腔及型芯分布的設(shè)計。因為零件尺寸較小，精度難以保證，經(jīng)過與袁老師的交流，最終解決了遇到的難題。在模具中，我用到了潛伏澆口，保證了塑件的表面質(zhì)量。
然后，我用CAD2006繪制了模具總裝圖及成型零件圖，并對成型零件進行了工藝卡片的編制，在這個過程中我對CAD軟件應(yīng)用有了很大的提高。最后經(jīng)過整理草稿、查閱資料，完成了說明書的編寫。
在整個設(shè)計過程中，袁老師給了我很大的幫助和指導(dǎo)，在這里我要衷心的感謝他。同時我也要感謝那些給我意見和建議的同窗們。
設(shè)計的過程就是一個不斷詢問、不斷思考、不斷修改、不斷完善的過程。在這個過程中我的專業(yè)知識得到了鞏固，在其他方面我們也會學(xué)到很多。
畢業(yè)設(shè)計即將完成，我也即將畢業(yè)，但求知的道路不會因此而中斷。走出校門社會將成為我更大的課堂。我會更加努力做好自己經(jīng)手的每件事。
謝 辭
本畢業(yè)設(shè)計歷時數(shù)月，現(xiàn)已基本定稿。在設(shè)計過程中我得到了很多老師和同學(xué)的幫助。在此，我要感謝那些所有曾經(jīng)給過我?guī)椭睦蠋熀屯瑢W(xué)。
首先，我要感謝我的指導(dǎo)老師袁小江，在我的設(shè)計過程中袁老師給了我很多意見和建議，使我的畢業(yè)設(shè)計更加完善、更加嚴謹。袁老師學(xué)識淵博、工作認真負責(zé)，在他身上我不僅學(xué)到了扎實的專業(yè)知識，在獨立思考、虛心求教、為人處世等方面也讓我受益良多。在此，我謹向袁老師表示衷心的感謝和深深的敬意。
同時，我也要感謝三年來給我授課的所有老師，在他們的悉心指導(dǎo)下，使我在專業(yè)及非專業(yè)知識上都獲得了很多。我也要感謝我的學(xué)校無錫科技職業(yè)學(xué)院，是她為我提供了良好的學(xué)習(xí)和生活環(huán)境，讓我的生活更加豐富，讓我的求知更加深遠，讓我的人生更加精彩。
最后，我要感謝所有曾經(jīng)給過我?guī)椭耐瑢W(xué)們，在我的畢業(yè)設(shè)計過程中，他們給了我很多寶貴的意見和建議，在生活上他們也給了我很多幫助。在此，我要衷心的感謝他們。
參考文獻
1.馬之庚. 工程塑料手冊 機械工業(yè)出版社 2004.3 第一版
2.屈華昌. 塑料成型工藝與模具設(shè)計 高等教育出版社 2006.7 第二版
3.史鐵梁. 模具設(shè)計指導(dǎo) 機械工業(yè)出版社 2008.1 第一版
4.林曉新. 工程制圖 機械工業(yè)出版社 2005.7 第一版
5.勞動和社會保障部教材辦公室組織 模具安裝調(diào)試及維修 中國勞動社會保障出版社 2005.7 第一版
6.吳兆祥. 模具材料及表面處理 機械工業(yè)出版社 2008.2 第一版
7.鄧 明. 實用模具設(shè)計簡明手冊 北京機械工業(yè)出版社 2006.1 第二版
8.付建軍. 模具制造工藝 機械工程出版社 2007.5 第一版
9.柳舟通 余立剛. 模具制造工藝學(xué) 北京科學(xué)出版社 2005 第一版
10.楊占堯. 注塑模具典型結(jié)構(gòu)圖冊 化工工業(yè)出版社2005.8 第一版
11.孫學(xué)強.機械制造基礎(chǔ) 機械工業(yè)出版社 2008.7 第二版
12.鄧昭銘 張瑩. 機械設(shè)計基礎(chǔ) 高等教育出版社 2000 第二版
13.徐茂功 桂定一. 公差配合與技術(shù)測量 機械工業(yè)出版社 2007.12 第二版
13.魯昌國 黃宏偉. 機械制造技術(shù) 大連理工大學(xué)出版社 2005.2 第二版
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外文資料翻譯
系 別 XXXXXXX
專 業(yè) XXXXX
班 級 XXXX
姓 名 XXX
學(xué) 號 XXXXX
指導(dǎo)教師 XXXXXX
2010年4月
Compression casting craft and compression casting mold design main point
Abstract: The die-casting machine, the mold and the alloy three, take press the casting as this, among the compression casting craft penetration, their conformity is organically a effective system, causes the die-casting machine and the mold obtains the good match, plays the optimization to press the casting structure, the optimal die-casting machine, the optimization presses the mold design, enhances the craft operating point the flexible role, thus provides the reliable guarantee for the compression casting production.Therefore, the compression casting craft lies within in the mold saying, depth of the connotation is self-evident.
Key word: Die-casting machine; Mold; Compression casting craft; The mold designs
1.Die-casting machine - mold - alloy system
Die-casting machine, the mold and alloy these three factors, in presses in the casting production process, they constituted a system, namely the die-casting machine - mold - alloy system, it is take presses the casting as this, among the craft penetration, entrusts with the system vigor and the efficiency, but the mold is the craft enters the system the platform.The die-casting machine, the mold and the alloy three relations expressed vividly as shown in Figure 1.
The die-casting machine - mold - alloy system main performance is:
(1)Ingate position influence backfill metal melt flow direction and the condition, with the backfill die space quality, have the decisive influence to the mold structure and the craft, this is the key is at.
(2)Designation best sufficient time, this is extremely important one step, affects to sufficient time metal melt rate of volume flow (Q), also is the sufficient power, according to the above and computation ingate size.
(3)Choice exhaust, overflow position and size, except outside normal exhaust, pollution discharge and temperature balance, but also may reduce the impact pressure, avoids the metal splashing and producing the burr.
(4) Heating and cooling, balanced mold temperature, maintenance operating temperature.
2.Compression casting crafts and the mold design key technologies
When compression casting the ingate position influence presses the casting the structural design, the quality and the compression casting mold design, may obtain the correct establishment ingate position prompt through the inquiry material.As a result of the casting structure multiplicity, must choose the ingate the correct position is very difficult, but also has some basic requests, like thought generally the establishment ingate must cause sufficient when the metallic jet has as far as possible compared the long distance by the open jet in the die space average, also is the correct ingate position, the shape, the size (flows to angle) to coordinate the compression casting parameter to be possible to obtain the metallic jet to expand along the wall unceasing order, to change, and continuously expands to the terminus.The die space majority (i.e. branch die space) completes by the jet flow backfill, only then a small part of die space (i.e. non-branch die space) by the metal melt branch supplemented completes or collides by the metal melt stock class completes the backfill, and overflows the system elimination vestiges through the platoon.Figure 2 is in the pouring position and branch die space schematic drawing [1]”.
The identical pressure casting choice different ingate position and flows to the angle, when may obtain the area percentage which the different branch die space, the non-branch die space and hold respectively, Figure 2 the shell compression casting, because the ingate position is different, obtains the different branch die space and the non-branch die space.The chart 2a ingate is vertical to one side wall, because the components crown long square edged orifice separates two sidewalls, the result is only then one side for the branch die space; Must fill another one side wall, must pass through the running channel both sides attachment point, the final two liquid flow gathering completes the packing, this part is the non-branch die space.Because the branch die space accounts for the area percentage not to be high, therefore can produce the massive waste products, like chart 2a1.In chart 2b, the ingate position does not make the change, only is wall thickness and so on crown rectangle Kong Yong craft muscles connects, like this fills when the metal melt changes, fills another one side wall along the muscle board, caused two sidewalls both to become the branch die space, increased the branch die space to account for the percentage, the casting quality also large scale enhances, like chart 2b1.In chart 2c, the components and chart 2a are same, the crown square edged orifice does not add the craft muscle, but establishes the ingate in a components end, such metal melt simultaneously carries on the backfill from two sidewalls, thus expanded the branch die space percentage, had guaranteed the quality, enhanced the qualified rate.This is the identical components three kind of ingate establishment plan, the proof ingate position crucial nature.
Although the computer technology is helpful to the designation ingate position, but the computer technology is only one method, but the ingate position design did not lose was still a key technologies.
Between 3 compression casting craftmain point
3.1 metal pressures, the speed and the current capacity relations
In the principle the die-casting machine are a liquid metal pump, it transports under the pressure the metal melt to the compression casting model cavity in.The pump characteristic is transports the power (rate of volume flow), is the pressure function, this aspect as early as in the 70's, first makes the valuable development work by Australian Asia CSIRO, has established a useful tool with the pQ2 chart, according to the casting i.e. mold request, decided the machine the adjustment value, is originally uses in the hot cell die-casting machine the zinc base alloy pressing in the casting, but very quick expands to Leng Shiji on.In principle, now the pressure and the rate of volume flow relations which knew very well from the hydromechanics principle, shifts to the die-casting machine practical application.
The metal pressure is higher, is also quicker in the spray nozzle and the ingate place metal melt flow rate, but also must consider victory flow resistance which as a result of the flowing section change, the direction change and the wall roughness existence produces, xi expresses sum of the these resistance with the friction coefficient.
If the known immeasurable steel coefficient xi, may calculate the metal pressure which certain ingate speed needs, according to the compression casting alloy and the casting request, the ingate speed has an empirical value, should observe, see Table 1, therefore needs the die-casting machine to provide the corresponding speed.
Table 1 ingate speed selection
Table 1 Choice of velocity at ingate
Project
A1
Mg
Cu
Zn
υa(m.s-1)
25-60
40-90
30-45
30-50
The low value uses in the relatively thick casting, the high value uses in the relatively thin casting, common magnesium alloy casting ingate speed compared to aluminum high25%. Time the vacuum die casting ingate speed is 15-30m/s.
3.2 Take the casting as this, optimizes the die-casting machine - mold - alloy system, enhances the craft flexibility
In the die-casting machine - mold - alloy system, through the adjustment craft parameter, may improve presses the casting the quality and the performance.These craft parameter defined with work window (OW).This indicated OW is these craft parameter limit chart.In the compression casting craft, the sufficient time, the ingate speed and the final metal static pressure use to define OW, these parameters and sufficient phenomenon related, relies on in the mold design and the die-casting machine performance.Designs when the mold, in OW all spots were considered all is equal, and does not have the priority, may think the best operating point exists in OW unknown lights, in presses the mold installs on the die-casting machine in front of the experimental mold is unable to find it.In the mold design stage guaranteed easy to find the good operating point is based on the flexible consideration, the flexibility is obtains in OW through the adjustment.
Therefore, divides into the craft parameter the soft parameter and the hard parameter two kinds, the soft parameter is refers through the operation or a control device carries on the adjustment the parameter, like parameters and so on power level, metal pressure, melt temperature, mold temperature and cycle time.The die-casting machine which the hard parameter is refers to which one kind to have to revise the mold or simultaneously must revise, like drift diameter, ingate area, air discharge duct and so on.Soft parameter when experimental mold easy to change and to obtain successfully, the hard parameter changes then both the difficulty and costs a great deal of money, time-consuming, needs to disassemble the mold frequently in order to revise.Therefore, the optimized method is and expands the OW internal assignment integral point based on the soft parameter the flexibility, thus provides the great scope for the mold experiment, avoids the time-consuming expensive mold change.
3.3 shoots the curve from the pressure to mention
Now die-casting machine Chang Peiyi three level of compression casting systems: The level advances gradually for the drift idling speed, pushes the metal melt to the ingate, namely the so-called slow pressure shoots the stage; The second level is the drift by high speed the metal melt through the ingate, fills the die space in the stipulation time, namely sufficient stage; The third level for the casting which not yet completely coagulates under the high pressure (starts pressure intensifier) to carry on the coagulation and by the compaction, namely compaction stage.Shown in Figure 17 for the model three levels of pressures shoots the curve schematic drawing, attempts the curvature to divide into the level slow pressure to shoot, two levels sufficient and three level of turbo-charged compaction three stages.Some pressures shoot the system to shoot the level pressure divide into two small parts, the first part is the drift seals up the pouring material mouth (shown in Figure 18 the X1 line) first, the second part shoots the stage for the slow pressure, then carries on the light again and the compaction, this became four levels of pressures to shoot the system, like this except might avoid the melt splashing the pouring material mouth, might raise the compression chamber initial fullness.
3.3.1. Slow pressures shoot the stage
Slow pressure to shoot the stage mainly are elect in the craft to control the slow pressure to shoot the speed, the goal are wells up when the metal melt to the ingate, presses in the room the gas to be able completely from the runner to enter the die space, but by the metal melt package, does not avoid in the casting forming the blowhole; Therefore, needs to choose a critical drift speed, may be the constant acceleration, also may be the constant speed, said generally, the constant acceleration effect is good.The overseas die-casting machine matches by “Parashot'' or “SIMUI” the constant acceleration slow pressure shoots the speed elects to control the system, Figure 19, chart 20[2] may take elects to control the slow pressure to shoot reference the speed.
3.3.2. Sufficient stages
This stage most should pay attention in the craft: The sufficient time, the pressure shoot the speed, the ingate speed and the air pressure shoot the speed the reciprocity, and mainly wants the parameter the choice.
3.3.2.1.Best sufficient time
The sufficient time is the metal melt has flowed the ingate, by the high ingate speed, fills the die space before the metal melt stop flowing the time.This time is very short, is an extremely essential parameter, selects the die-casting machine, carries on foundation which the technological design and the mold design.
The sufficient time must be short, the goal is sufficient when does not have the early time in the casting smallest spot or the liquid flow far-end to coagulate, avoids the casting appearing lacks flaws and so on meat, cold shot.The sufficient time is shorter, the sufficient speed is higher, can enlarge the die space to wear, but but also possible to splash because of zhang the metal and to produce the edge; The sufficient speed is high, can enable in the die space the gas not to have the enough time to transgress from the die space.The sufficient time correct choice only then the overall evaluation can obtain, Table 3 gave has chosen the sufficient time and ingate speed correlation factor [4].
The metal melt had decided from the operating temperature to the temperature of solidification release quantity of heat it maintains the castability under the same thermal conductivity time, therefore this kind of thermal then achievement determines its may imitate the time criterion most greatly.The release quantity of heat and the sufficient time are proportional, compared to may obtain several kind of alloy sufficient time relations according to the quantity of heat.The Mg alloy, the Zn alloy, the A1 alloy and the Cu alloy under the same coagulation condition, from the operating temperature to the temperature of solidification release quantity of heat respectively are 261, 329, 509, 918kCal/dm3, then they the time ratio is τMg: τZn: τAI: τCu ≈0.51: 0.65:1:1.8.In other words, τMg=: 0.51τAI, τZn=0.65τAI, τCu=1.8τAI.
When compression casting obvious molten metal in die space not superheat, the people observe the melt to flow have certain quantity solid phase, when the solid phase rate achieved30%-80%, In the die space the bath movement only can through the high rate of inflow, when best sufficient time according to type (17) computation, quite Yu Fzhi is70%-80%.
The best sufficient time speaking of each kind of magnesium alloy shoots when the pressure must the aluminum alloy be quicker than at least 2 times, the copper alloy best sufficient time and the alloy composition element related, the leaded brass (CuZn37Pb) and the magnesium alloy is close, the silicon brass (CuZnl5Si4) and the aluminum alloy is close.
The casting surface quality quantity increases along with the sufficient time changes, the sufficient time is short, the pressure shoots the power to be big, sufficient is quick, but because of the ingate thickness limit, the excessively short sufficient time causes the casting the factor of porosity increase.Figure 22 is the sufficient time presses the casting quality to the aluminum influence [7].Chart 23[3,8] is one kind which the recent years proposed to the aluminum, the magnesium presses the casting wall thickness and the sufficient time relations relational graph.The superficial quality requests to choose the short sufficient time high.
3.3.2.2 Pressure shoots the speed, the sufficient speed and the air pressure shoots the speed.
(1) Pressure shoots the speed (drift speed)
The pressure to shoot the speed (drift speed) is in the sufficient stage unit time drift displacement.In traveling schedule curve sufficient stage no matter what chooses two spots, the survey traveling schedule distance and the sufficient time, then obtain the pressure to shoot the speed = survey the distance (mm)/pressure to shoot time (ms).
(2)Sufficient speed (ingate speed)
The sufficient speed is the ingate speed, concerns with the drift speed and the drift area.In presses in the room - - mold this loop system, take the sufficient time metal passes the ingate rate of volume flow Q as the foundation.Only then after designated generally the die-casting machine, can determine the drift area, the ingate speed may according to Table 1 selection.
The ingate speed is the important parameter, has the important influence to the casting quality and the mold life.The ingate speed excessively is high can increase the die space surface because corrodes, sticks the probability which the mold receives damages; Although the low ingate speed is advantageous in the gas discharges from in vivo, but also can cause the casting mechanics performance and the surface quality goes bad.The casting volume flaw often appears by the uniform distribution micro hole or by the big hole in the casting, high ingate speed compression casting strength ratio low ingate speed low, is helpful in forms the micro hole in the casting, causes the casting surface to be brighter and cleaner, the organization is more compact.
Ingate speed and casting wall thickness related, but decided by the ingate thickness, the actual same wall thickness casting, possibly has the different thickness ingate, from this also can use the different ingate speed to come the compression casting.
But has to ingate structure experience graph [2], confirmed the ingate structure and the ingate speed, when to casting quality influence, recommendation fine casting operating point region thin-walled casting, in choice neighbor chart grid area.Obviously, when very thin ingate, because the ingate parameter is the low value, the need higher ingate speed.
Sufficient time drift speed υo excessively high, besides to mold life and casting quality influential, but also can because the sufficient end time drift impact function, has caused to move, to decide the mold to push, when is pushed the slit to surpass 0.05-0.15 mm, but also can produce the molten metal the phenomenon which splashes from the mold comes out.
Sufficient time ingate speed υa with casting wall thickness and metal melt in die space flow length related, as shown in Figure 27.
(3) Biggest air pressure shoots the speed
Biggest air pressure to shoot speed υot max is presses in the room not to have in the situation which the metal also the governor valve all start, in unit time drift displacement.It is the cold room die-casting machine important technical parameter, to has the metal sufficient time drift speed υ0, in the running channel speed υa and presses the casting quality to have the important influence.
(a) Compression casting machine-pressed shoots the power which the system can provide
For in the short sufficient time introverted die space to fill the large capacity metal melt, needs the high drift speed and in the running channel speed, this must entrust with the die-casting machine high biggest air pressure to shoot the speed.The modern Europe die-casting machine biggest air pressure shoots the speed to achieve 11m/s, Japan recent years also appeared 10m/s the supervelocity die-casting machine.
(b) Air pressure shoots the speed
Air pressure to shoot the speed is the die-casting machine adjustable parameter.Because presses the room - die space system resistance the existence, the sufficient time drift speed always shoots the speed the air pressure to be much smaller than.May know by chart 30[4], when certain in running channel area υot max increases from 4m/s to 8m/s, but the sufficient time drift speed υo enhances from 2.4m/s (I) to 3.1 m/s(II), does not look like υot max such to enhance 1 time.
Theoretically, when the pressure shoots the output is biggest υ02/υ ot max2=Q2/Q at max2=1/3, then υ0/υot max2=Q/Qot max=0.577, as shown in Figure 31.Thenυ0=0.577 upsilon ot max.
The cold-press room die-casting machine must have the high level most greatly spatial
Pressure to shoot the speed, like this may improve the craft operating point spiriactiveness.The graphic solution may help us to choose the die-casting