【正文】 m nothing if not that! In his text he expounds on the idea that one must give their life a purpose. And that is the true topic of this entry. These last four years have been so easy: teach for a grand total of six hours a week, and the rest of my time is mine. Since I39。s cultural foray overseas, has been widely panned by its home audience. Retitled Empresses in the Palace, the American version has been shortened from its original 76 episodes at 45 minutes each, to six 90minute episodes. The quick pacing threw off many native viewers, who are accustomed to a more leisurely daytimesoapstyle narrative rhythm. (Chinese TV stations would run two or three episodes every day.) I did not finish the fulllength version and found the truncated one not difficult to follow. What39。t help but sing the folk songs, Nasun says. The vastness of Inner Mongolia and the lack of entertainment options for people living there, made their lives lonely. The nomadic people were very excited about our visits, Nasun recalls. We didn39。謝 辭首先，在此我衷心感謝導師趙佩鳳副教授對我的精心指導。所以，活塞桿直徑去25mm,油缸直徑取160mm，選型號T5026型油缸。一般夾緊裝置的動力方式有氣壓式、液壓式、電動式、氣液聯(lián)動式裝置。 夾緊機構的設計為了保證夾壓后工件定位的穩(wěn)定和減少工件的夾緊變形,夾緊力的方向應工件在夾具上定位的主要加工基準面。兩定位銷孔直徑：D1=D2=?切削邊銷寬度，查表D2=,取b=4mm 工件在加工時，為保證加工表面對其他表面的位置尺寸精度和位置精度，必須使它相對于刀具和切削成形運動（有機床提供）處于正確的加工位置。 零件的定位工件在夾具中或在機床上的定位，是通過工件的定位基準面和夾具定位元件相接觸（支撐定位）或相配合（定心定位）來實現(xiàn)的，因此工件定位方式及夾具定位元件的選擇完全取決于工件定位基準面的形狀。這三個部分起著不同的作用: ①中間傳動機構能夠改變作用力的大小和方向；②夾緊元件則用以承受中間傳動機構傳遞的夾緊力，并與工件直接接觸而執(zhí)行夾緊動作；③夾緊動力部分用于產(chǎn)生動力源，并將作用力傳給中間傳動裝置。為了避免產(chǎn)生廢品以及經(jīng)常修理定位支承元件的麻煩, 設計時必須注意下述的幾個問題: ①合理安排定位支承元件,盡量使其組成較大的定位支承平面，最好能讓夾壓力的位置對準定位支承元件，如果受工件結(jié)構限制不能實現(xiàn), 也要使定位支承元件盡量靠近夾壓力的作用線, 并使夾壓力的合力中心處處在定位支承平面內(nèi)。按照專用機床夾具的主要功能, 結(jié)構可分為三大部分, 即刀具導向裝置、定位支承系統(tǒng)和夾緊機構。軟件適應性很好，可以及時修改，這樣給新產(chǎn)品試制，實行新的工藝流程和試驗均提供了方便。(2)有毛坯加工成成品的過程中，工件不能時效，內(nèi)應力難以消除。二十世紀70年代以來，加工中心得到迅速發(fā)展，出現(xiàn)了可換主軸箱加工中心，它備有多個可以自動更換的裝有刀具的多軸主軸箱，能對工件同時進行多孔加工。查《組合機床設計手冊》 v=10m/min f=n=1000vπd=100010π9=＇=355r/minv＇=πdn＇1000=π93551000=ap=L=5+√3=t=Lfn＇=355==工序12 ，查《組合機床設計手冊》 v=20m/min f=n=1000vπd=100020π=＇=1135r/minv＇=πdn＇1000=π11351000=ap=L=5+7+√3=t=Lfn＇=1135==工序13 ，查《組合機床設計手冊》 v=10m/min f=n=1000vπd=100010π6=＇=530r/minv＇=πdn＇1000=π65301000=ap=L=5+6+1=12mmt=Lfn＇=530==9s工序14 45176。113孔工序12 ，工序13 ，工序14 45176。 擬訂工藝過程擬定工藝路線的原則 (1)先面后孔由于平面面積較大，定位穩(wěn)定可靠，因此先加工平面，再以此面定位加工其它表面，可以簡化夾具結(jié)構、減少零件安裝變形，從而提高加工精度。同時，充型時液流和氣流方向一致，能減少氣孔的生成。（2）生產(chǎn)節(jié)拍代入公式τ=TN,得該零件的生產(chǎn)節(jié)拍。冷卻方法有兩種，一種是水冷，另一種是風冷。根據(jù)缸體與油底殼安裝平面的位置不同，通常把缸體分為以下三種形式。發(fā)動機缸體是發(fā)動機零件中結(jié)構較為復雜的箱體類零件，其將缸蓋、油底殼、曲軸等相關零件連接成一個整體，使這些零件相互之間保持正確的相對位置，彼此能夠協(xié)調(diào)工作，它的制造精度要求較高，并且加工工藝復雜。發(fā)動機缸體結(jié)構特征復雜，加工精度要求高，因此對發(fā)動機缸體的加工要從生產(chǎn)線的每一個環(huán)節(jié)進行控制。國內(nèi)發(fā)動機生產(chǎn)廠商，以中外合資企業(yè)為主，如上海通用、上海大眾、一汽大眾、東風雪鐵龍、東風日產(chǎn)、長安福特、北汽福田、廣州豐田、廣州本田、上汽通用五菱等。發(fā)動機缸體的傳統(tǒng)提高生產(chǎn)效率和加工質(zhì)量的方式是盡量縮短輔助時間和采用剛性生產(chǎn)線，這種方式在今天已經(jīng)不適應生產(chǎn)的發(fā)展。要提高發(fā)動機的使用性能，就必須控制發(fā)動機制造過程中關鍵零件的加工精度與加工質(zhì)量。關鍵詞: 發(fā)動機缸體 工藝規(guī)程 專用夾具AbstractThe quality of the engine’s manufacturing influenced the performance of the car, as the engine is the heart of the motor vehicles. The accuracy of the manufacturing of the engine block has an important relationship with the overall performance, because the engine block is the fundamental part in the system of the engine. We have to control the machining accuracy and machining quality.With the development of our economy and rapidly growing demand for cars in China, how to improve the production efficiency and processing quality of auto parts, is crucial to the development of automobile industry. Engine cylinder block is one of the five major parts, and its production efficiency and processing quality are directly related to production efficiency and performance of the car. The traditional method to improve production efficiency and processing quality is trying to shorten the auxiliary time and adopt the way of a rigid line, which is already out of date in the current production. Therefore, how to improve the efficiency of engine cylinder block production and processing quality is an important research, and the WD615 engine used in heavy vehicles, including all kinds of engineering machinery, buses, power generation equipment, ships and other ideal power of engine, its cylinder processing design has greater significance. In this paper, we focus on the first step of the process and made research on the process. The engine block belongs to the block pieces, which is plicated in structure and easy to be deformed. We could adopt crankshaft bore as the positioning datum to ensure the accuracy. As the junction surface has a big area and a high demand of the accuracy and roughness, including high amount of the machining parts and high demand of the machining and the long routine of the processing, we have to adopt Horizontal machining center to improve the machining quality and efficiency. The task of the paper is mainly about the reasonable choice on the machining tools and calculation on the fixtures.Keyword: Engine cylinder Technological procedure Special fixture目 錄 1 前 言 12被加工零件分析 2 被加工零件所屬部件的應用及產(chǎn)品簡介 2 被加工零件的技術要求 23工藝規(guī)程設計 4 生產(chǎn)綱領及節(jié)拍的確定 4 毛坯的選擇 4 擬訂工藝過程 5 各工序切削用量的選擇與計算 64設備的選擇 13 13 13 13 135 專用夾具設計 15 專用機床夾具概述 15 定位方案的確定 16 16 18 19 19 夾緊機構的設計 20 20 20 21 21結(jié) 論 23謝 辭 24參考文獻 25附 錄 261 前 言汽車工業(yè)是國民經(jīng)濟中的支柱性產(chǎn)業(yè)。而發(fā)動機缸體是汽車發(fā)動機的基礎零件，通過它把發(fā)動機的曲軸連桿機構和配氣機構以及供油、潤滑、冷卻等機構聯(lián)接成一個整體。驗證、加深、鞏固和擴大已學過的專業(yè)基礎理論和部分專業(yè)知識，了解和掌握本專業(yè)的實際生產(chǎn)知識，為以后的工作打下基礎。汽車發(fā)動機的缸體和上曲軸箱常鑄成一體，稱為缸體——曲軸箱。(3)隧道式缸體：這種形式的缸體曲軸的主軸承孔為整體式，采用滾動軸承，主軸承孔較大，曲軸從缸體后部裝入。3工藝規(guī)程設計 生產(chǎn)綱領及節(jié)拍的確定（1）生產(chǎn)綱領依設計題目可知：Q=10000件/年，n=1件/臺；結(jié)合生產(chǎn)實際，備品率α和廢品率β分別取為10%和1%。汽缸體宜采用低壓鑄造。 ，清理費用低，鑄件外觀好。104孔工序4 ，工序5 45