發(fā)動(dòng)機(jī)缸體外文翻譯

1、.發(fā)動(dòng)機(jī)缸體發(fā)動(dòng)機(jī)缸體是發(fā)動(dòng)機(jī)零件中結(jié)構(gòu)較為復(fù)雜的箱體零件，其精度要求高，加工工藝復(fù)雜，且加工質(zhì)量的好壞直接影響發(fā)動(dòng)機(jī)整機(jī)性能，因此，它成為各發(fā)動(dòng)機(jī)生產(chǎn)廠家所關(guān)注的重點(diǎn)零件之一。 1發(fā)動(dòng)機(jī)缸體的工藝特點(diǎn) 發(fā)動(dòng)機(jī)缸體是發(fā)動(dòng)機(jī)的基礎(chǔ)零件和骨架，同時(shí)又是發(fā)動(dòng)機(jī)總裝配時(shí)的基準(zhǔn)零件。缸體的作用是支承和保證活塞、連桿、曲軸等運(yùn)動(dòng)部件工作時(shí)的準(zhǔn)確位置；保證發(fā)動(dòng)機(jī)的換氣、冷卻和潤(rùn)滑；提供各種輔助系統(tǒng)、部件及發(fā)動(dòng)機(jī)的安裝。 1.1 工藝特點(diǎn) 缸體為一整體鑄造結(jié)構(gòu)，其上部有4個(gè)缸套安裝孔；缸體的水平隔板將缸體分成上下兩部分；缸體的前端面從前到后排列有三個(gè)同軸線的凸輪軸安裝孔和惰輪軸孔。 缸體的工藝特點(diǎn)是:結(jié)構(gòu)、形

2、狀復(fù)雜；加工的平面、孔多；壁厚不均，剛度低；加工精度要求高，屬于典型的箱體類加工零件。缸體的主要加工表面有頂面、主軸承座側(cè)面、缸孔、主軸承孔及凸輪軸孔等，它們的加工精度將直接影響發(fā)動(dòng)機(jī)的裝配精度和工作性能，主要依靠設(shè)備精度、工夾具的可靠性和加工工藝的合理性來(lái)保證。 2發(fā)動(dòng)機(jī)缸體工藝方案設(shè)計(jì)原則和依據(jù) 工藝方案是工藝準(zhǔn)備工作的總綱，是工藝規(guī)程設(shè)計(jì)和關(guān)鍵工藝裝備設(shè)計(jì)的指導(dǎo)文件。正確的工藝方案設(shè)計(jì)，有助于系統(tǒng)地運(yùn)用新的科學(xué)技術(shù)成果和先進(jìn)的生產(chǎn)經(jīng)驗(yàn)，保證產(chǎn)品質(zhì)量，改善勞動(dòng)條件，提高工藝技術(shù)和工藝管理水平。 2.1 工藝方案設(shè)計(jì)的原則 設(shè)計(jì)工藝方案應(yīng)在保證產(chǎn)品質(zhì)量的同時(shí)，充分考慮生產(chǎn)周期、成本和環(huán)境保護(hù)

3、；根據(jù)本企業(yè)能力，積極采用國(guó)內(nèi)外先進(jìn)的工藝技術(shù)和裝備，不斷提高企業(yè)工藝水平。發(fā)動(dòng)機(jī)缸體機(jī)械加工工藝設(shè)計(jì)應(yīng)遵循以下基本原則: (1) 加工設(shè)備選型原則 加工設(shè)備選型采用剛?cè)峤Y(jié)合的原則，加工設(shè)各以臥式加工中心為主，少量工序采用立式加工中心，關(guān)鍵工序一曲軸孔、缸孔、平衡軸孔加工采用高精度高速臥式加工中心，非關(guān)鍵工藝一上下前后四個(gè)平面的粗銑采用高效并有一定調(diào)整范圍的專用機(jī)床加工； (2) 集中工序原則 關(guān)鍵工序一機(jī)體缸孔、曲軸孔、平衡軸孔的精加工及缸蓋結(jié)合面的精銑，采用集中在一道工序一次裝夾完成全部加工內(nèi)容的方案，以確保產(chǎn)品精度滿足缸體關(guān)鍵品質(zhì)的工藝能力和有關(guān)技術(shù)要求； (3) 全部夾具均采用液壓夾具

4、，夾緊元件、液壓泵及液壓控制元件采用德國(guó)或美國(guó)產(chǎn)優(yōu)質(zhì)可靠元器件； (4) 整線全部采用濕式加工，采用單機(jī)獨(dú)立排屑，高精度關(guān)鍵加工工序的臥式加工中心采用恒溫冷卻并加裝高精度高壓雙回路帶旁通精過(guò)濾系統(tǒng)，加工中心全部帶有高壓內(nèi)冷。 根據(jù)汽車發(fā)動(dòng)機(jī)缸體的工藝特點(diǎn)和生產(chǎn)任務(wù)要求，發(fā)動(dòng)機(jī)缸體機(jī)械加工自動(dòng)生產(chǎn)線由臥式加工中心CWK500和CWK500D加工中心、專用銑/鏜床、立式加工中心matec-30L等設(shè)備組成。 (1) 頂?shù)酌婕巴呱w止口面粗銑組合機(jī)床 本機(jī)床為雙面臥式專用銑床，采用移動(dòng)工作臺(tái)帶動(dòng)工件，機(jī)床采用進(jìn)口西門子S7-200PLC系統(tǒng)控制，機(jī)床設(shè)獨(dú)立電控柜，切削過(guò)程自動(dòng)化完成，有自動(dòng)和調(diào)整兩種狀

5、態(tài)； (2) 高速臥式加工中心CWK500該加工中心可實(shí)現(xiàn)最大流量的濕加工，但由于設(shè)備自動(dòng)排屑處理系統(tǒng)是通過(guò)位于托盤下的內(nèi)置寬式排屑器而完成，該加工中心可以進(jìn)行干加工；機(jī)床主軸轉(zhuǎn)速6000r/min，快速進(jìn)給速度38m/min； (3) 前后端面粗銑組合機(jī)床 機(jī)床采用液壓傳動(dòng)；控制系統(tǒng)采用進(jìn)口西門子S7-200PLC系統(tǒng)控制，機(jī)床具有一定的柔性； (4) 專用機(jī)床TXK1500 本機(jī)床由立式加工中心改造而成型，具備立式加工中心的特點(diǎn)及性能，該機(jī)床具有高強(qiáng)度、高耐磨度、高穩(wěn)定性、高精度、高配置等優(yōu)點(diǎn)； (5) 高速立式加工中心matec-30L該加工中心主軸最高轉(zhuǎn)速9000r/min?？刂葡到y(tǒng)采

6、用西門子公司SINUMERIK840D控制系統(tǒng)； (6) 高速臥式加工中心CWK500D主軸最高轉(zhuǎn)速15000r/min。 2.2 工藝方案設(shè)計(jì)的依據(jù) 影響發(fā)動(dòng)機(jī)缸體零件的工藝方案設(shè)計(jì)因素是多方面的。具體地說(shuō)，可以從以下幾個(gè)方面理解。 (1) 產(chǎn)品對(duì)象、產(chǎn)品圖樣和有關(guān)技術(shù)文件根據(jù)發(fā)動(dòng)機(jī)缸體的復(fù)雜程度、精度要求等采取相應(yīng)的工藝措施。生產(chǎn)對(duì)象為四缸汽車發(fā)動(dòng)機(jī)缸體； (2) 產(chǎn)品的生產(chǎn)綱領(lǐng)、生產(chǎn)性質(zhì)和生產(chǎn)類型該發(fā)動(dòng)機(jī)缸體年生產(chǎn)綱領(lǐng)為40000萬(wàn)件； (3) 工作制度設(shè)備年有效工作日為320天，平均設(shè)備負(fù)荷率為80%,兩班制，16小時(shí)/天。 3發(fā)動(dòng)機(jī)缸體機(jī)械加工工藝設(shè)計(jì)的主要內(nèi)容 發(fā)動(dòng)機(jī)缸體結(jié)構(gòu)復(fù)雜，

7、精度要求高，尺寸較大，是薄壁零件，有若干精度要求較高的平面和孔。發(fā)動(dòng)機(jī)缸體機(jī)械加工的工藝特點(diǎn)是:主要是平面和孔的加工，加工平面一般采用刨、銑削等方法加工，加工孔主要采用鏜削，加工小孔多用鉆削。由于缸體結(jié)構(gòu)復(fù)雜，因此如何保證各表面的相互位置精度是加工中的一個(gè)重要問題。 3.1 毛坯的選擇 發(fā)動(dòng)機(jī)缸體采用的材料一般是灰鑄鐵HT150、HT200、HT250，也有采用鑄鋁或鋼板的，此發(fā)動(dòng)機(jī)缸體采用高強(qiáng)度合金鑄鐵。缸體在加工前進(jìn)行時(shí)效處理，以消除鑄件內(nèi)應(yīng)力和改善毛坯的力學(xué)性能。 提高毛坯精度，減少加工余量，是提高自動(dòng)生產(chǎn)線系統(tǒng)生產(chǎn)率及加工質(zhì)量的重要措施。由于國(guó)外箱體類零件毛坯質(zhì)量和精度較高，其生產(chǎn)線系

8、統(tǒng)己實(shí)現(xiàn)了毛坯直接上線，既省去了毛坯檢查裝置，也節(jié)省了由于毛坯質(zhì)量問題而浪費(fèi)的加工工時(shí)，提高了綜合效益。因此，精化毛坯是提高生產(chǎn)率最有潛力的出路。對(duì)于發(fā)動(dòng)機(jī)缸體生產(chǎn)線，可在零件上線前粗銑六個(gè)面，去除大部分余量，便于零件直接上線。 3.2 機(jī)械加工工藝基準(zhǔn)的選擇與加工 選擇合理的加工工藝基準(zhǔn)，直接關(guān)系到能否保證零件的加工質(zhì)量。一般地說(shuō)，工藝基準(zhǔn)可分為粗基準(zhǔn)和精基準(zhǔn)。 (1) 粗基準(zhǔn)對(duì)于上線的毛坯，其粗基準(zhǔn)的選擇尤為重要，如果粗基準(zhǔn)選擇不合理，會(huì)使加工余量分布不均勻，加工面偏移，造成廢品。在缸體生產(chǎn)線中，我們采用側(cè)面為粗基準(zhǔn)； (2) 精基準(zhǔn)對(duì)于發(fā)動(dòng)機(jī)缸體這種箱體零件來(lái)說(shuō)，一般采用“一面兩銷”為全

9、線的統(tǒng)一基準(zhǔn)。對(duì)于較長(zhǎng)的自動(dòng)生產(chǎn)線系統(tǒng)，由于定位銷孔在使用過(guò)程中的磨損影響發(fā)動(dòng)機(jī)缸體零件定位，因此，將定位銷孔分為2-3段使用。在缸體定位銷孔的加工中，我們采用了以側(cè)面、底面和主軸孔定位，在加工中心上加工。 3.3 機(jī)械加工加工階段的劃分和工序的安排 一個(gè)零件往往有許多表面需要加工，當(dāng)然表面的加工精度是不同的。加工精度較高的表面，往往要經(jīng)過(guò)多次加工；而對(duì)于加工精度低的表面，只需要經(jīng)過(guò)一兩次就行了。因此，擬訂工藝順序時(shí)，要抓住“加工精度高的表面”這個(gè)矛盾，合理安排工序和合理劃分加工階段。安排工藝順序的原則是:先粗后精，先面后孔，先基準(zhǔn)后其它。在發(fā)動(dòng)機(jī)缸體的機(jī)械加工中，同樣應(yīng)遵循這一原則。 (1)

10、 粗加工階段 在發(fā)動(dòng)機(jī)缸體的機(jī)械加工過(guò)程中，安排粗加工工序，對(duì)毛坯全面進(jìn)行粗加工，切去大部分余量，以保證生產(chǎn)效率； (2) 半精加工階段 在發(fā)動(dòng)機(jī)缸體的機(jī)械加工中，為了保證一些重要表面的加工精度，安排一些半精加工工序，將精度和表面粗糙度要求中等的一些表面加工完成，而對(duì)要求高的表面進(jìn)行半精加工，為以后的精加工做準(zhǔn)備； (3) 精加工階段 對(duì)精度和表面粗糙度要求高的表面進(jìn)行加工； (4) 次要小表面的加工 如螺紋孔，可以在精加工主要表面后進(jìn)行，一方面加工時(shí)對(duì)工件變形影響不大，同時(shí)廢品率也降低；另外，如果主要表面出廢品后，這些小表面就不必再加工了，從而避免浪費(fèi)工時(shí)。但是，如果小表面的加工很容易碰傷主

11、要表面時(shí)，就應(yīng)該把小表面加工放在主要表面的精加工之前； (5) 輔助工序也要妥善安排 如檢驗(yàn)工序，在零件粗加工階段之后，關(guān)鍵工序加工前后，零件全部加工完畢后，都要適當(dāng)安排。 對(duì)加工階段進(jìn)行劃分，具有以下好處:首先，可以在粗加工后采取措施消除工件內(nèi)應(yīng)力，保證精度；其次，精加工放在后面，不至于在運(yùn)輸過(guò)程中損壞工件己加工表面；再次，先粗加工各面，可以及早發(fā)現(xiàn)毛坯缺陷并及時(shí)處理，不會(huì)浪費(fèi)工時(shí)。不過(guò)對(duì)于一般小工件就不要分得很細(xì)。 3.4 缸體的主要加工表面和輔助工序缸體主要加工表面和輔助工序有: (1) 平面加工 目前，銑削是發(fā)動(dòng)機(jī)缸體平面加工的主要手段，國(guó)內(nèi)銑削進(jìn)給量一般為300-400mm/min，

12、與國(guó)外銑削進(jìn)給量2000-4000mm/min相比，相差甚遠(yuǎn)，有待于提高，因此，提高銑削進(jìn)給量，縮短輔助時(shí)間，是提高生產(chǎn)效率的主要途徑，發(fā)動(dòng)機(jī)缸體精加工一些平面時(shí)的銑削進(jìn)給量達(dá)到2399 mm /min，大大提高了效率 頂面的銑削是缸體加工中的一個(gè)關(guān)鍵工序，其平面度要求為0.02/145mm，表面粗糙度為Ra1.6um。在缸體的加工中，采用側(cè)面和主軸軸承孔定位，頂面、底面和中間瓦蓋止口面同時(shí)加工，在加工中采用線外對(duì)刀裝置，能較好地滿足發(fā)動(dòng)機(jī)缸體加工精度要求； (2) 一般孔系的加工 一般孔系的加工仍采用傳統(tǒng)的鉆、擴(kuò)、鏜、鉸、攻絲等工藝方法。課題在設(shè)計(jì)具體的工藝方案時(shí)，采用涂層刀具、內(nèi)冷卻刀具等

13、先進(jìn)刀具，并采用大流量冷卻系統(tǒng)，大大提高了切削速度，提高了生產(chǎn)率； (3) 深油孔加工 傳統(tǒng)的加工方法是采用麻花鉆進(jìn)行分級(jí)進(jìn)給，其生產(chǎn)效率低，加工質(zhì)量差。在發(fā)動(dòng)機(jī)缸體深油孔的加工中，采用槍鉆工藝； (4) 三軸孔的加工 三軸孔的加工為缸體孔系加工中精度要求高，工時(shí)長(zhǎng)的限制性工序。因此，工序安排、加工方法、刀具等都應(yīng)特別注意。合蓋前加工，即缸體半圓孔和主軸承蓋的荒加工，其主要目的是去除毛坯余量、釋放應(yīng)力，為后序加工做準(zhǔn)備；在加工中心上加工曲軸孔時(shí)，采用雙面鏜孔，先在曲軸孔一端鏜孔到1/2長(zhǎng)度時(shí)，然后工作臺(tái)回轉(zhuǎn)180度，從另外一端再鏜另一1/2長(zhǎng)。 (5) 缸孔的加工 缸孔的加工是缸體機(jī)械加工中的

14、關(guān)鍵工序之一，一般情況下，其加工工藝過(guò)程為粗鏜、半精鏜、精鏜和珩磨。為及早發(fā)現(xiàn)缸孔內(nèi)壁的鑄造缺陷，消除應(yīng)力，應(yīng)盡量提前粗鏜缸孔；由于缸孔的結(jié)構(gòu)特點(diǎn)不同，需采用珩磨工藝，以提高缸孔表面質(zhì)量。在大批量生產(chǎn)中，缸孔的珩磨一般采用多軸珩磨機(jī)或珩磨自動(dòng)線。在此我們采用珩磨自動(dòng)線，由粗珩.精珩和檢測(cè)三臺(tái)設(shè)備組成； (6) 清洗 清洗分為濕式清洗和干式清洗。缸體機(jī)械加工自動(dòng)生產(chǎn)線采用大流量濕式清洗； (7) 檢測(cè) 檢測(cè)分在線檢測(cè)和線外檢測(cè)兩種。在發(fā)動(dòng)機(jī)缸體的質(zhì)量檢測(cè)中，根據(jù)實(shí)際情況采用線外檢測(cè)，主要采用三坐標(biāo)測(cè)量機(jī)對(duì)缸體進(jìn)行綜合測(cè)量，每200件抽查1-5件，每班抽查一件。 3.5 缸體加工切削用量的選擇 發(fā)

15、動(dòng)機(jī)缸體切削用量的選擇包括切削速度、進(jìn)給量和進(jìn)給速度的選擇。由于加工中所使用的設(shè)備都是具有較高精度和剛度的機(jī)床和高速加工中心，為保證切削加工的效率，可以適當(dāng)選擇較大的切削用量。發(fā)動(dòng)機(jī)缸體的主要加工表面為平面和軸承孔、缸孔等孔的加工，而平面和軸承孔、缸孔的加工方式主要是銑削和鏜削，因此這里討論的切削用量的選擇主要是銑削和鏜削切削用量的選擇。(1) 銑削量的選擇 銑削用量的選擇直接關(guān)系到銑削效果的好壞。一般地說(shuō)，銑削用量的選擇原則是:端面銑刀銑削時(shí)首先應(yīng)盡可能取較大的銑削深度和銑削寬度，然后盡可能選取較大的銑削速度。在具體選擇銑削用量時(shí)所涉及的因素很多，但總的來(lái)說(shuō)，粗銑時(shí)工件余量大，加工要求低，主

16、要考慮銑刀的耐用度；精銑時(shí)余量小，加工精度要求高，主要考慮加工質(zhì)量的提高； 在發(fā)動(dòng)機(jī)缸體的銑削加工中，選用的機(jī)床為具有高剛度的高速機(jī)床，功率大，剛性好，因而選擇了比較大的切削用量。 (2) 鏜削用量的選擇 鏜削用量的選擇根據(jù)粗、精加工工藝的不同而不同。粗加工時(shí)，選用較大的切削深度，精加工時(shí)，選用較小的切削深度。切削深度確定以后，盡可能選用較大的切削用量。在切削深度和進(jìn)給量選定以后，可在保證刀具合理耐用度的條件下，用計(jì)算或查表的方法來(lái)確定切削速度。一般地，粗加工時(shí)，選擇較低的切削速度，精加工時(shí)，選用較高的切削速度。 在發(fā)動(dòng)機(jī)缸體的鏜削加工中，選用的機(jī)床為具有高剛度的高速機(jī)床，功率大，剛性好；刀具

17、為國(guó)外先進(jìn)的刀具，質(zhì)量高，剛性好，因而選擇了比較大的切削用量。4小結(jié) 通過(guò)對(duì)發(fā)動(dòng)機(jī)缸體的結(jié)構(gòu)和工藝特點(diǎn)進(jìn)行分析，論述了發(fā)動(dòng)機(jī)缸體機(jī)械加工工藝方案設(shè)計(jì)的原則和依據(jù)以及切削用量的選擇，并以高速銑削和調(diào)頭鏜孔為例，設(shè)計(jì)、分析了發(fā)動(dòng)機(jī)缸體的高速銑削和調(diào)頭鏜孔工藝過(guò)程，及在加工中需要注意的問題。Engine partsEngine parts in the engine block is a more complex structure of spare parts box, its high precision, processing, complex process, and the process

18、ing quality will affect the overall performance engine, so it has become the engine manufacturers focus parts one.Engine block is the basic engine parts and skeleton, when the general assembly of the base components. Cylinders role is supporting and ensuring the piston, connecting rod, crankshaft an

19、d other moving parts work, the exact location; to ensure the engine ventilation, cooling and lubrication; to provide a variety of auxiliary systems, components and engine installation. 1.1 Technical Characteristics Cylinder cast for a whole structure, and its upper part 4 cylinder mounting hole; cyl

20、inder standard cylinder is divided into upper and lower divisions into two parts; cylinder to the rear of the front-side arrangement of the previous three coaxial mounting hole of the camshaft and the idler axle hole.Cylinder process features are: the structure of complex shape; processing plane, mo

21、re than holes; uneven wall thickness and stiffness is low; processing of high precision typical of box-type processing part. The main processing of the surface of cylinder block top surface, the main bearing side, cylinder bore, the main and camshaft bearing bore holes and so on, they will directly

22、affect the machining ccuracy of the engine assembly precision and performance, mainly rely on precision equipment, industrial fixtures reliability and processing technology to ensure the reasonableness. Technology program is the preparation of the master process is to process planning and key proces

23、s equipment design guidance documents. The correct process of program design, facilitate the systematic application of new scientific and technological achievements and advanced production experience, to ensure product quality, improve working conditions, and improve process technology and process m

24、anagement level. 2.1 Process design principles Design Technology program should be to ensure product quality at the same time, give full consideration to the production cycle, cost and environmental protection; based on the enterprises ability to actively adopt advanced process technology and equipm

25、ent, and constantly enhance their level of technology. Engine block machining process design should follow the following basic principles: (1) The selection of processing equipment, processing equipment, the principle of selection adopted the principle of combining rigid-flexible, processing each ho

26、rizontal machining center is located mainly small operations with vertical machining center, the key process a crank hole, cylinder hole, balancer shaft hole High-speed processing of high-precision horizontal machining center, an upper and lower non-critical processes before and after the four-dimen

27、sional high-efficiency rough milling and have a certain adjustment range of special machine processing; (2) focus on a key process in principle process the body cylinder bore, crankshaft hole, Balance Shaft hole surface finishing and the combination of precision milling cylinder head, using a proces

28、s focused on a setup program to complete all processing elements in order to ensure product accuracy The key quality processes to meet the cylinder capacity and the relevant technical requirements; (3) All fixtures are used hydraulic clamp, clamping components, hydraulic pumps and hydraulic control

29、components used in Germany or the United States producing high quality and reliable components;(4) The whole line used in all wet processing, using standalone BTA, high-precision machining processes critical horizontal machining center with constant cooling and to install high-precision high-voltage

30、 double-circuit band-pass fine filtration system, all with high-pressure processing center in the cold.According to the technological characteristics of automobile engine cylinder block and the production mandate, the engine block machining automatic production line is composed of horizontal machini

31、ng center CWK500 and CWK500D machining centers, special milling / boring machine, vertical machining centers matec-30L and other appliances. (1) top and bottom, and tile covered only the combination of aperture rough milling machine dedicated to this machine to double-sided horizontal milling machin

32、e, using moving table driven parts, machine tools imported Siemens S7-200PLC system control, machine control cabinet set up an independent, cutting automate the process is completed and two kinds of automatic and adjust the state; (2) high-speed horizontal machining center machining center can be re

33、alized CWK500 the maximum flow of wet processing, but because of equipment, automatic BTA treatment system through the built-in tray under the wide-type chip conveyor and the completion of the machining center can be dry processing; machine tool spindle speed 6000r/min, rapid feeding speed 38m/min;(

34、3)The combination of front and rear face rough milling machine tool using hydraulic transmission; control system imported Siemens S7-200PLC system control, machine tools have a certain flexibility; (4) The special machine TXK1500 this machine vertical machining center by the modification of shape, w

35、ith vertical machining center features and performance, this machine has high strength, high wear-resistant, high stability, high accuracy, high-profile etc.; (5) high-speed vertical machining center matec-30L of the machining center spindle high speed 9000r/min. Control system uses Siemens SINUMERI

36、K840D control system; (6) high-speed horizontal machining center spindle CWK500D highest speed 15000r/min. 2.2 Process design basis Affect the engine block part of the process design factors are manifold. Specifically, can be understood from the following aspects. (1) product object, product drawing

37、s and technical documents related to the complexity of the engine block under the precision requirements of the process to take corresponding measures. Production targets for the four-cylinder automobile engine cylinder block; (2) the production program, the production of the nature and type of prod

38、uction of the engine block the production program of 400 million; (3) The annual effective system of work equipment, working for 320 days, with an average equipment loading rate of 80%, two shifts, 16 hours / day. Engine block complex structure, high precision, large size, is thin-walled parts, ther

39、e are a number of high precision plane and holes. Engine block machining process characteristics: mainly flat and the hole processing, processing of flat generally use planing, milling methods such as processing, processing of hole used mainly boring, processing and multi-purpose drilling holes. As

40、the cylinder complex structure, so how to ensure that the mutual position of the surface processing precision is an important issue. 3.1 The selection of blank Engine block on the materials used are generally gray cast iron HT150, HT200, HT250, there is also cast aluminum or steel plate, this engine

41、 block using high-strength alloy cast iron. Cylinder in the processing prior to aging treatment in order to eliminate stress and improve the rough casting mechanical properties. Improve the rough accuracy, reduction of machining allowance, is to improve the automated production line system productiv

42、ity and processing quality of the important measures. As the foreign box-type parts of rough quality and high precision, and its production-line system has been implemented directly on the blank line, not only eliminating the need for blank check device also saves the rough quality problems due to w

43、aste of machining time, increase overall efficiency. Therefore, the refinement of rough is to improve the productivity of the most promising way out. For the engine block production line, can be rough in parts on-line pre-milling six face, removing most of the margin, to facilitate direct on-line pa

44、rts. 3.2 machining process selection and processing of the benchmark Choose the right processing technology base is directly related to the processing quality can ensure the parts. Generally speaking, process benchmarking can be divided into coarse and fine reference base. (1) The baseline for the o

45、n-line thick rough, which is particularly important the choice of benchmark crude, if crude benchmark choice unreasonable, will the uneven distribution of machining allowance, processing and surface offsets, resulting in waste. In the cylinder production line, we have adopted for the coarse side of

46、the base; (2) refined the base of this box for the engine block parts, the general use of “side two sales” for a full range of uniform benchmarks. For the longer automated production line system, due to pin holes in the course of the wear and tear caused by inaccurate positioning, therefore, will be

47、 divided into 2-3 segment pin holes used. In the cylinder pin hole of the process, we have adopted to the side, bottom and the spindle hole positioning, in the processing center on the process. 3.3 Machining Processing Stages and processes of the arrangements Often a part of many apparent need for p

48、rocessing, of course, the surface machining accuracy are different. Processing of high precision surface, often after repeated processing; As for the processing of the surface of low precision, only need to go through one or two on the list. Thus, when the development process in order to seize the “

49、processing high precision surface,”this conflict, the reasonable arrangement processes and rational division stage of processing. Arrange the order of the principle of process is: after the first coarse refined, the first surface after the hole, the first benchmark other. In the engine block machini

50、ng, the same should follow this principle. (1) roughing stage engine block machining process, the arrangements for roughing process, to fully carry out rough rough, trim most of the margin in order to ensure production efficiency; (2) semi-finishing phase of the engine block machining, in order to e

51、nsure the accuracy of some important surface processing, and arrange some semi-finishing operations, will be required accuracy and surface roughness of the surface of the middle of some processing to complete, while demanding the surface of semi-finished, to prepare for future finishing; (3) The fin

52、ishing stage of requiring high accuracy and surface roughness of the surface processing; (4) secondary processing, such as small surface screw holes, you can finish of the major surface after the one hand, when the workpiece deformation process little impact at the same time also reduced the rejecti

53、on rate; In addition, if the main surface of a waste, these small the surface will not have to be processed, thus avoiding a waste of man-hours. However, if the processing is very easy for a small surface bumps the main surface, it should be placed on a small surface finish prior to the main surface

54、 finishing; (5) should make proper arrangements for secondary processes such as product inspection process, in part roughing stage, the key process before ining Processing Stages and processTand after processing, spare parts all the processing has been completed, should be appropriate arrangements.

55、Stage of processing division, has the following advantages: First, it can take measures to eliminate the rough workpiece after the stress, to ensure accuracy; second, finishing on the back, and will not damage during transport the surface of the workpiece has been processed; again, first roughing th

56、e surface defects can be detected early and promptly deal with rough, do not waste working hours. But most small parts, do not sub very thin. 3.4 cylinder surface of the main processing and secondary processes Cylinder surface and support the main processing operations are: (1) plane processing At p

57、resent, the milling of engine blocks is the primary means of planar processing, domestic milling feed rate is generally 300-400mm/min, and foreign 2000-4000mm/min milling feed rate compared to far cry, to be on increasing, therefore, improve the milling feed rate, reduce overhead time is to improve

58、the productivity of the major means of finishing a number of plane engine block when the milling feed rate to reach 2399 mm / min, greatly improved efficiency; Top surface of the cylinder milling is a key process in the process, the flatness requirements for 0.02/145mm, the surface roughness of Ra1.

59、6um. Processing in the cylinder, the use of side and spindle bearing bore positioning, top, bottom and middle vagay only aperture while processing used in the processing line outside of the knife device can better meet the engine block machining accuracy ; (2) General holes machining holes in general are still using the traditional p