液压机锻件机械加工余量与公差.doc

液压机锻件机械加工余量与公差 1. 范围本标准规定了水压机上自由锻件机械加工余量与公差的一般要求。本标准适用于在水压机上自由锻造的碳素钢及一般合金钢锻件；本标准适用于单件和小批量生产。2. 一般规定21 本标准规定的余量与公差，可按不同的工艺要求加在零件加工图所标注的基本尺寸上；若是粗加工图，其余量则可按0.8a1.0a选取。22 本标准规定锻件上、下公差各为相应余量的1/3。23 锻件不加工表面上的公差，根据锻件的形状和尺寸，按本标准确定，余量为零。24 锻件的基本尺寸的个位数数值圆整到0或5。25 试制产品的余量和公差可比本标准的数值适当放大。3. 各类锻件余量与公差31 圆轴、方轴和矩形截面类自由锻件的机械加工余量与公差:LD、A、B200200250250315315400400500500630630800800160022724826828930103211341116002500227248268289301032113411371225004000248268289301032113411371240134000630026828930103211341137124013431463008000289301032113411371240134314461580001000030103211341137124013431446151000012500331135123712401343144615491612500160003612381340134314461549161600020000401342144414471550165318当长径比L/D或L/A等于或大于15时，截面上的双面余量取1.2a；大于30时，取1.3a,上下公差相应放大。32台阶轴类自由锻件的机械加工余量与公差：LD、D1、D2180180250250350350450450550550650650800800100010001200120015002482692893010321134113612381340134214150025002692893010321134113612381340134214441525004000289301032113411361238134013421444154615400060003010321134113612381340134214441546154816600080003211341136123813401342144415461548165017800010000341136123813401342144415461548165017521710000120003612381340134214441546154816501752175418120001400038134013421444154615481650175217541856191400016000421444154615481650175217541856195819160001800046154816501752175418561958196020180002000050175217541856195819602062211台阶轴类均按最大截面D和总长L选取余量a。2带法兰轴锻件,其总长/轴直径15时，法兰余量取1.1a；30时，法兰余量取1.2a。33 台阶轴台阶锻出的最小长度L1和最小高度h1：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特殊情况或必要时，小于以上最小锻出长度，也可锻出。LD025025035035045045055055065065075075085085015002020202025251500250020202025252530250040002020202525253030400060002020252530303535600080002525253030353540800010000253030353540401000012000303035354040451200035354040454534 端部法兰、中间凸缘最小长度L、L1：d1D1、D2500500600600700700800800900900100010001100110012001200130013002001101401802002402003001001201601902202602903203603004007010014017020024027030034038040050060901201501802202502803203505006007010013016020023026030032060070080110140180210240280300700800100130160200220260280端部法兰若剁刀切平，按表列数值增30%，若为氧割切平，按表列数值选取。3. 5方块类自由锻件的机械加工余量与公差方块类自由锻件的机械加工余量与公差LA、B40040050050065065080080010001000125012501500150065026928930106508002893010321134118001000301032113411361238131000125032113411361238134013421412501500341136123813401342144415461515001750361238134013421444154615481650161750200038134013421444154615481650165217余量a决定于长度L及每边尺寸A、B；长度上的余量采用较大边余量。36 圆饼类、冲孔类自由锻件的机械加工余量与公差：不带孔圆盘尺寸D/H6时，允许锻件带有鼓形。冲孔件孔径极限尺寸的计算见下式：dmax=0.37D+6dmin=0.208H+33式中:D冲孔前锻坯直径，单位为毫米（mm）；H冲孔前锻坯高度，单位为毫米（mm）。HD6306308008001000100012501250155015501850185022002200250321134113612381340134314471651172504003411361238134013421445154916531840063036123813401342144415471651175518630100038134013421444154615491653185719100012504214441546154816511755181250155046154816501753181550501752175518余量a决定于长度L及每边尺寸A、B；长度上的余量采用较大边余量。37 芯棒扩孔类自由锻件的机械加工余量与公差如下：HD10001000125012501600160020002000250025003150315028032113612401344154916541828040034113813421447165217571963214005603712411445155017551860206728560750401344154816531858196421712475010604314471651175619612068237525106014004615501754185920652272248027140019005418581963216923772685281 当零件尺寸D3000时，锻件壁厚B=（D-d）/2+a应不小于0.054D，并且100mm。2 当零件尺寸D3000时，锻件壁厚B应165mm。38 筒体类自由锻件的机械加工余量与公差：零件长度 L零 件 尺 寸 D3504004005005006306308008001000100012501250140014001600160018001800200020002150100030103210341136123812100116003210341136123812401342144414160125003411361238124013421444144715501653175618591925014000361238124013421444144715501653175618591962204001630038124013421444144715501653175618591962206521630190004214441447155016531756185919622065216822900111000471550165317561859196220652168227123110011200050165317561859196220652168227123拔长比 L/H 与余量系数 n 的关系L/H1.11.11.21.21.31.31.41.41.51.51.61.61.71.71.81.81.91.92.02.02.1n1.31.61.92.22.52.83.13.43.74.04.3L/H2.12.22.22.32.32.42.42.52.52.72.73.03.0n4.64.95.25.55.86.06.0注：1、筒体壁厚不允许小于100mm，台小于100mm，可增加至100mm。2、当内径d230 mm且锻件长度L2000mm时，或者内径d280 mm且锻件长度L3000mm时，锻件上的孔允许不锻出。3、长度余量与公差分别是最大外径余量与公差的n倍。n为增加系数，根据拔长比查表确定。39 单拐曲轴和错移多拐曲轴自由锻件的机械加工余量与公差：曲拐长度 L零 件 尺 寸 D300300450450600600bhL1bhL1bhL1bhL13003311401350163511421355183712441455183913