零件的结构工艺性课件

ManufacturingProcessConsiderations

零件的结构工艺性Castingstructure

铸件结构Commonmachiningstructures机加工常见结构Structureofdrillhole钻孔结构请点击相应标题显示其内容ManufacturingProcessConsider1

Castingstructure铸件结构SandboxcoverOverflowPouringhead

上砂箱冒口浇口1.

Draft起模斜度:The1

20（≈3°）draftalongthedrawingdirectionofthepatternfacilitatestotakeoutthepatternwhilemolding.

铸件造型时，为便于取出木模，沿脱模方向的表面做出1

20（≈3°）的起模斜度。请点击鼠标左键显示后面内容Ifthedraftisverysmall,itcanbeomitted,Ifnecessary,itcanbeincludedintechnical.起模斜度较小时,在图中一般不画出,必要时可注写在技术要求中。Sandbox下砂箱Model模型Cavity型腔Sand型砂Castingstructure铸件结22.Filletsincastings铸造圆角:

Theremustbearadiuswheretwosurfacesmeet,inordertoavoidsanddropswhileremovingthemouldandshrinkagecavityandshrinkagecrackwhilecooling.在铸件表面相交处应有圆角,以免脱模时砂型落砂,同时防止铸件冷却时产生裂纹或缩孔。Machinesymbol机加工符号请点击鼠标左键显示后面内容

Castingstructure铸件结构

Theintersectionlineisneededinordertodistinguishthevarioussurfaces.Theonewehaveprovidediscalledrun-outline.Therepresentationofatransitionlineissimilartothatofintersectionline.Theonlydifferenceisthattheendoftherun-outlineisnotconnectedwiththecontourlineoftheradius,andthelinestyleisathinsolidline.

为了区分不同形体的表面,仍要画出相贯线,这种相贯线称为过渡线。过渡线的画法和相贯线相同,只是其端点处不与圆角轮廓线接触,且线型为细实线。2.Filletsincastings铸造圆角:33.Wallthickness铸件的壁厚:Toavoidshrinkagecavityandshrinkagecrackcausedbydifferentcoolingspeeds.Duringthedesignphase,itisamusttomaintainuniformwallthicknessorasmooth.Onemustavoidunequaldesignssuchasthicknessabruptvaryingorlocalthickpartialareas.为防止浇铸零件时,由于壁厚不匀而冷却速度不同产生的缩孔和裂纹,在设计铸件时,应使壁厚尽量均匀或逐渐过渡,以避免壁厚突变或局部肥大的不匀现象。Dedectivness

有缺陷Defectivness

有缺陷请点击鼠标左键显示后面内容Smoothtransition

平滑过渡

Castingstructure铸件结构Maintainuniformwallthickness壁厚均匀3.Wallthickness铸件的壁厚:41.Bossclubandrecessedsurface凸台与凹坑：

Usually,allsurfacesmountedonotherpartsneedtobemachined.Thebossorrecessedsurfaceisaddedtokeepgoodcontactbetweenthesurfacesoftwopartsandtoreducethemachiningareaandmanufacturingcost.零件上凡与其他零件接触的表面一般都要加工，为了保证两零件表面的良好接触，同时减少加工面积，以降低制造费用，在零件的需接触表面处常设计成凸台、凹坑的形式。请点击鼠标左键显示后面内容凸台凹坑高度不一致,导致加工调刀工时费、成本高Commonmachiningstructures机加工常见结构Onemustavoidunequaldesigns

应避免凸台凹坑高度不一致1.Bossclubandrecessedsurf52.

Chamferandround倒角与圆角:Toeliminateburrsandflashesinordertopreventhumanhandsfromcuttingandtofacilitatemounting,theendsofboththeshaftandtheholeusuallyneedtobechamfered.为了去除零件的毛刺、锐边，以防止划伤人手和便于装配，在轴和孔的端部通常需加工出倒角。Avoidcracks避免断裂Thatis,thesharpedgeofshaftendiscutbyaconicalcuttingtoolwitha45°degreeapexangle.即用一锥顶角为45°的圆锥刀头切除其端部锐边。请点击鼠标左键显示后面内容Commonmachiningstructures机加工常见结构C22×C2Anarctransitionusuallyremainsattheshaftshoulder,whichiscalledround,inordertoavoidcrackscausedbypressureconcentration.在轴肩处，常常制成圆弧过渡，即圆角，以避免因应力集中而产生裂纹。2.Chamferandround倒角与圆角:6Commonmachiningstructures机加工常见结构Undercut退刀槽Undercut退刀槽Grindingundercut砂轮越程槽Grindingundercut砂轮越程槽Grindingsurface精磨表面Grindingsurface精磨表面3.

Escapeandgrindingundercut螺纹退刀槽和砂轮越程槽:Anescape,grindingortravelinglimitundercutneedstobeproducedattheendofthesurfacetobemachined,inordertoeasilywithdrawthecutterorgrindingwheelwhiletappingorgrindingexternaldiameter.在车削螺纹或磨外圆时,为便于退刀或使用砂轮,需要在待加工面末端先切出退刀槽或砂轮越程槽。请点击鼠标左键显示后面内容Thedimensionoftheescapeisidentifiedas‘width×depth’or‘width×diameter’.

退刀槽及越程槽的尺寸注成“宽度×深度”或“宽度×直径”。Commonmachiningstructures机加7Theaxisofthedrillshouldbeperpendiculartothesurfacetobedrilled,inordertoensurecorrectdrillingpositionandpreventthedrillfrombreakingcausedbyunequalimpactforce.用钻头钻孔时，为保证钻孔位置准确和避免钻头因受力不均而折断，应使钻头轴线垂直于被钻孔零件的表面。请点击鼠标左键显示后面内容Structureofdrillhole钻孔结构Theintersectionpointwheretheholeandtheobliqueplanemeetisnecessarytosettoplatformandnotchstructure.Iftheanglebetweenthedrillandtheobliqueplaneislargerthan60°,onecandrilltheholedirectly.在与孔轴线倾斜的表面处,常需设计出平台或凹坑结构,但当钻头与倾斜面的夹角大于60°时,也可以直接钻孔。Theaxisofthedrillshoul8本小节结束谢谢您的认真学习！退出前一页本小节结束谢谢您的认真学习！退出前一页9

Castingstructure铸件结构不与轮廓线接触在图片上点击鼠标左键“暂停”或再次“播放”Castingstructure铸件结10

Castingstructure铸件结构在切点附近断开在图片上点击鼠标左键“暂停”或再次“播放”Castingstructure铸件结11

Castingstructure铸件结构在图片上点击鼠标左键“暂停”或再次“播放”Castingstructure铸件结12

Castingstructure铸件结构在图片上点击鼠标左键“暂停”或再次“播放”Castingstructure铸件结13Commonmachiningstructures机加工常见结构Commonmachiningstructures机加14请点击鼠标左键显示后面内容Grindingsurfacebygrindingwheel

砂轮正在精磨工件的表面Commonmachiningstructures机加工常见结构请Grindingsurfacebygrinding15Structureofdrillhole钻孔结构

Surfacestructureofthedrillhole钻孔的表面结构

Representationoftheholeanddimensionofadrill钻孔的尺寸标注Structureofdrillhole16Grindingexternaldiameterbygrindingwheel

砂轮正在精磨斜齿轴的外圆面Grinding