汽车连杆加工工艺及钻螺栓孔专用夹具毕业设计论文

摘要连杆是柴油机的主要传动件之一，本文主要论述了连杆的加工工艺及其夹具设计。连杆的尺寸精度、形状精度以及位置精度的要求都很高，而连杆的刚性比较差，容易产生变形，因此在安排工艺过程时，就需要把各主要表面的粗精加工工序分开。逐步减少加工余量、切削力及内应力的作用，并修正加工后的变形，就能最后达到零件的技术要求。安排工艺进程时，就要把各主要表面的粗、精加工工序分开，即把粗加工安排在前，半精加工安排在中间，精加工安排在后面。这是由于粗加工工序的切削余量大，因此切削力、夹紧力必然大，加工后容易产生变形。粗、精加工分开后，粗加工产生的变形可以在半精加工中修正；半精加工中产生的变形可以在精加工中修正。本课题夹具设计为钻连杆螺栓孔专用夹具设计。关键词:加工工艺；加工余量；尺寸链；夹具设计ASTRACTTheconnectingrodisoneofthemaindrivingmediumofdieselengine,thistextexpoundsmainlythemachiningtechnologyandthedesignofclampingdeviceoftheconnectingrod.Theprecisionofsize,theprecisionofprofileandtheprecisionofposition,oftheconnectingrodisdemandedhighly,andtherigidityoftheconnectingrodisnotenough,easytodeform,soarrangingthecraftcourse,needtoseparatetheeachmainandsuperficialthickfinishmachiningprocess.Reducethefunctionofprocessingthesurplus,cuttingforceandinternalstressprogressively,revisethedeformationafterprocessing,canreachthespecificationrequirementforthepartfinally,Arrangetechnologyprocess,themainsurfacecoarse,finishingprocess,theformer,halfinbalancingarrangementinthemiddle,finishmachiningprecisionarrangementinbehind.Thisisduetotheroughmachiningprocesses,thuscuttingallowanceofcuttingforce,clampingforceinevitablelargedeformation,processedeasily.Afterfinishingseparatecoarse,moldings,deformationoffinishinginhalf,Halfofmachiningdeformationoffinishingin.Thisfixturedesignfordrillconnectingboltholespecialjigdesign.Keyword:Processingtechnology；Limits.but；Dimensionchain；Fixturedesign目录第1章绪论......................................................11.1设计任务.....................................................11.2加工工艺规程设计的目的和意义.................................11.3连杆加工的发展趋势...........................................1第2章汽车连杆加工工艺规程设计.................................32.1连杆的结构特点...............................................32.2连杆的主要技术要求...........................................32.2.1大、小头孔的尺寸精度、形状精度..............................32.2.2大、小头孔轴心线在两个互相垂直方向的平行度..............32.2.3大、小头孔中心距........................................42.2.4连杆大头孔两端面对大头孔中心线的垂直度..................42.2.5大、小头孔两端面的技术要求..............................42.2.6螺栓孔的技术要求........................................42.2.7有关结合面的技术要求....................................42.3连杆的材料和毛坯.............................................52.4连杆的机械加工工艺过程.......................................62.5连杆的机械加工工艺过程分析...................................82.5.1工艺过程的安排..........................................82.5.2定位基准的选择..........................................82.5.3确定合理的夹紧方法......................................92.5.4连杆两端面的加工.......................................102.5.5连杆大、小头孔的加工...................................102.5.6连杆螺栓孔的加工.......................................102.5.7连杆体与连杆盖的铣开工序...............................112.5.8大头侧面的加工.........................................112.6连杆加工工艺设计应考虑的问题................................112.6.1工序安排...............................................112.6.2定位基准...............................................112.6.3夹具使用...............................................112.7切削用量的选择原则..........................................122.7.1粗加工时切削用量的选择原则............................122.7.2精加工时切削用量的选择原则............................132.8确定各工序的加工余量、计算工序尺寸及公差....................132.8.1确定加工余量..........................................132.9计算工艺尺寸链..............................................142.9.2连杆体的卡瓦槽的计算..................................142.10工时定额的计算.............................................152.10.1铣连杆大小头平面......................................152.10.2粗磨大小头平面........................................162.10.3加工小头孔............................................162.10.4铣大头两侧面..........................................172.10.5扩大头孔..............................................182.10.6铣开连杆体和盖........................................182.10.7加工连杆体............................................192.10.8铣、磨连杆盖结合面....................................202.10.9铣、钻、镗（连杆总成体）..............................212.10.10粗镗大头孔...........................................222.10.11大头孔两端倒角.......................................222.10.12精磨大小头两平面（先标记朝上）.......................222.10.13钻小头油孔............................................232.10.14半精镗大头孔及精镗小头孔.............................232.10.15精镗大头孔...........................................242.10.16小头孔两端倒角.......................................242.10.17镗小头孔衬套.........................................252.10.18珩磨大头孔...........................................252.11连杆加工工艺卡片及供需卡片填写..............................25第3章钻螺栓孔夹具设计.........................................263.1钻螺栓孔夹具设计............................................263.1.1问题的指出.............................................263.1.2夹具设计...............................................26(1)定位基准的选择..........................................26(2)夹紧方案................................................26(3)夹具体设计..............................................26(4)定位误差分析............................................273.2夹具体结构设计图............................................27结束语............................................