1．選擇基準的三個基本的要求：(1) 選擇基準應該能保證工件定位準確裝卸方便方便可靠。(2) 選擇基準與各加工部位的的尺寸計算簡單。(3) 保證加工精度。數控加工中心機床

　　2．選擇定(ding)(ding)位(wei)(wei)基(ji)(ji)準(zhun)6個(ge)原則(ze)：(1) 盡量的(de)(de)選擇設(she)計基(ji)(ji)準(zhun)作(zuo)為(wei)定(ding)(ding)位(wei)(wei)基(ji)(ji)準(zhun)；(2) 定(ding)(ding)位(wei)(wei)基(ji)(ji)準(zhun)和設(she)計基(ji)(ji)準(zhun)不(bu)能(neng)統一時(shi)，應(ying)該嚴(yan)格(ge)控制(zhi)定(ding)(ding)位(wei)(wei)誤差保(bao)證(zheng)加(jia)工(gong)精度；(3) 工(gong)件(jian)(jian)(jian)(jian)需要(yao)兩次(ci)以上(shang)裝(zhuang)夾(jia)(jia)(jia)(jia)(jia)加(jia)工(gong)時(shi)，所(suo)選基(ji)(ji)準(zhun)在(zai)一次(ci)裝(zhuang)夾(jia)(jia)(jia)(jia)(jia)定(ding)(ding)位(wei)(wei)能(neng)完(wan)成全(quan)部關鍵精度部位(wei)(wei)的(de)(de)加(jia)工(gong)；(4) 所(suo)選基(ji)(ji)準(zhun)要(yao)保(bao)證(zheng)完(wan)成可(ke)能(neng)多(duo)(duo)的(de)(de)加(jia)工(gong)內容；(5) 批量加(jia)工(gong)時(shi)，零件(jian)(jian)(jian)(jian)定(ding)(ding)位(wei)(wei)基(ji)(ji)準(zhun)應(ying)盡可(ke)能(neng)與建立工(gong)件(jian)(jian)(jian)(jian)坐(zuo)標(biao)(biao)系的(de)(de)對刀基(ji)(ji)準(zhun)重合(he)(he)；(6) 需要(yao)多(duo)(duo)次(ci)裝(zhuang)夾(jia)(jia)(jia)(jia)(jia)時(shi)，基(ji)(ji)準(zhun)應(ying)該前后統一。 加(jia)工(gong)中心(xin)(xin)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)的(de)(de)確定(ding)(ding)： 1．對夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)的(de)(de)基(ji)(ji)本(ben)要(yao)求：(1) 夾(jia)(jia)(jia)(jia)(jia)緊機(ji)構(gou)不(bu)得影響進(jin)給，加(jia)工(gong)部位(wei)(wei)要(yao)敞開；(2) 夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)在(zai)機(ji)床(chuang)上(shang)能(neng)實現定(ding)(ding)向安裝(zhuang)；(3) 夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)的(de)(de)剛性(xing)與穩定(ding)(ding)性(xing)要(yao)好。 2．常(chang)用(yong)(yong)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)種類：(1) 通用(yong)(yong)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)：如虎鉗、分(fen)度頭、卡(ka)盤等；(2) 組合(he)(he)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)：組合(he)(he)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)由一套結(jie)構(gou)已(yi)經(jing)標(biao)(biao)準(zhun)化、尺寸已(yi)經(jing)規(gui)格(ge)化的(de)(de)通用(yong)(yong)元件(jian)(jian)(jian)(jian)組合(he)(he)元件(jian)(jian)(jian)(jian)所(suo)構(gou)成；(3) 專用(yong)(yong)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)：專為(wei)某一項或類似(si)的(de)(de)幾項加(jia)工(gong)設(she)計制(zhi)造的(de)(de)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)；(4) 可(ke)調(diao)整(zheng)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)：組合(he)(he)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)與專用(yong)(yong)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)的(de)(de)結(jie)合(he)(he)，既能(neng)保(bao)證(zheng)加(jia)工(gong)的(de)(de)精度，裝(zhuang)夾(jia)(jia)(jia)(jia)(jia)更具(ju)(ju)(ju)靈(ling)活性(xing)；(5) 多(duo)(duo)工(gong)位(wei)(wei)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)：可(ke)同時(shi)裝(zhuang)夾(jia)(jia)(jia)(jia)(jia)多(duo)(duo)個(ge)工(gong)件(jian)(jian)(jian)(jian)的(de)(de)夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)；(6) 成組夾(jia)(jia)(jia)(jia)(jia)具(ju)(ju)(ju)：專門用(yong)(yong)于形狀相似(si)、尺寸相近且定(ding)(ding)位(wei)(wei)、夾(jia)(jia)(jia)(jia)(jia)緊、加(jia)工(gong)方法(fa)相同或相似(si)的(de)(de)工(gong)件(jian)(jian)(jian)(jian)的(de)(de)裝(zhuang)夾(jia)(jia)(jia)(jia)(jia)。數(shu)控加(jia)工(gong)中心(xin)(xin)機(ji)床(chuang)

   3．加工(gong)(gong)(gong)(gong)(gong)中心夾(jia)(jia)(jia)具(ju)(ju)的(de)(de)選用原則： (1) 在(zai)保證加工(gong)(gong)(gong)(gong)(gong)精度(du)和(he)生產(chan)效率的(de)(de)前提下，優先選用通(tong)用夾(jia)(jia)(jia)具(ju)(ju)； (2) 批量加工(gong)(gong)(gong)(gong)(gong)可考慮(lv)(lv)采(cai)用簡單(dan)專(zhuan)用夾(jia)(jia)(jia)具(ju)(ju)； (3) 大批量加工(gong)(gong)(gong)(gong)(gong)可考慮(lv)(lv)采(cai)用多(duo)工(gong)(gong)(gong)(gong)(gong)位夾(jia)(jia)(jia)具(ju)(ju)和(he)高(gao)效的(de)(de)氣壓、液(ye)壓等專(zhuan)用夾(jia)(jia)(jia)具(ju)(ju)； (4) 采(cai)用成(cheng)組(zu)工(gong)(gong)(gong)(gong)(gong)藝(yi)時應(ying)使(shi)用成(cheng)組(zu)夾(jia)(jia)(jia)具(ju)(ju)； 4．工(gong)(gong)(gong)(gong)(gong)件在(zai)機(ji)床(chuang)工(gong)(gong)(gong)(gong)(gong)作臺(tai)上(shang)的(de)(de)最佳裝夾(jia)(jia)(jia)位置：工(gong)(gong)(gong)(gong)(gong)件裝夾(jia)(jia)(jia)位置應(ying)保證工(gong)(gong)(gong)(gong)(gong)件在(zai)機(ji)床(chuang)各軸(zhou)的(de)(de)加工(gong)(gong)(gong)(gong)(gong)行程(cheng)范圍內(nei)，并且(qie)使(shi)得刀(dao)具(ju)(ju)的(de)(de)長度(du)盡可能縮短，提高(gao)刀(dao)具(ju)(ju)的(de)(de)加工(gong)(gong)(gong)(gong)(gong)剛性。數控(kong)加工(gong)(gong)(gong)(gong)(gong)中心機(ji)床(chuang)