先(xian)要(yao)(yao)明確準備加(jia)(jia)工的(de)(de)(de)對(dui)象。一般來說，具(ju)備下(xia)列特點的(de)(de)(de)零(ling)件(jian)(jian)適合(he)在加(jia)(jia)工中(zhong)心加(jia)(jia)工：多工序集約型工件(jian)(jian)指在一個工件(jian)(jian)上需(xu)要(yao)(yao)用(yong)許多把(ba)刀具(ju)進行(xing)加(jia)(jia)工。定位繁(fan)瑣的(de)(de)(de)工件(jian)(jian)例如有(you)一定位孔(kong)距精度要(yao)(yao)求的(de)(de)(de)多孔(kong)加(jia)(jia)工，利用(yong)機床定位精度高的(de)(de)(de)特點，很方便實(shi)施。重復生(sheng)產型的(de)(de)(de)工件(jian)(jian)適合(he)加(jia)(jia)工單(dan)件(jian)(jian)小批量(liang)生(sheng)產。小批量(liang)指在1-100件(jian)(jian)，每批數(shu)量(liang)不多，但(dan)又需(xu)要(yao)(yao)重復生(sheng)產。 

另(ling)外(wai)，即(ji)使工(gong)(gong)件(jian)(jian)(jian)形狀(zhuang)(zhuang)尺寸不(bu)同，但又是相似工(gong)(gong)件(jian)(jian)(jian)，易(yi)于實現成組(zu)加(jia)(jia)工(gong)(gong)工(gong)(gong)藝的(de)零(ling)件(jian)(jian)(jian)。復雜形狀(zhuang)(zhuang)的(de)零(ling)件(jian)(jian)(jian)模具、航空零(ling)件(jian)(jian)(jian)等復雜形狀(zhuang)(zhuang)工(gong)(gong)件(jian)(jian)(jian)，能借助自動(dong)程序編制技術在加(jia)(jia)工(gong)(gong)中心上(shang)加(jia)(jia)工(gong)(gong)各種異(yi)形零(ling)件(jian)(jian)(jian)。箱體(ti)類(lei)、板類(lei)零(ling)件(jian)(jian)(jian)在臥式加(jia)(jia)工(gong)(gong)中心上(shang)利(li)用回轉工(gong)(gong)作臺，對(dui)箱體(ti)零(ling)件(jian)(jian)(jian)進行(xing)多面加(jia)(jia)工(gong)(gong)，如主軸(zhou)箱體(ti)、泵體(ti)、閥體(ti)、內燃機缸體(ti)等。如果連頂面也(ye)要一次裝夾中加(jia)(jia)工(gong)(gong)，可選用五面體(ti)加(jia)(jia)工(gong)(gong)中心。 

適合加(jia)工(gong)箱蓋(gai)缸蓋(gai)、平面凸輪等。龍(long)門加(jia)工(gong)中心用于加(jia)工(gong)大型箱體、板類(lei)零(ling)件，如內燃(ran)機車(che)缸體、加(jia)工(gong)中心立柱、床身、印刷墻板機等。 

立式加(jia)工(gong)(gong)中(zhong)心規格的(de)(de)選定(ding)根據確(que)(que)定(ding)的(de)(de)加(jia)工(gong)(gong)工(gong)(gong)件(jian)的(de)(de)大小(xiao)尺寸，相應確(que)(que)定(ding)所(suo)需機床的(de)(de)工(gong)(gong)作臺尺寸和三個(ge)直線坐(zuo)標系的(de)(de)行程。工(gong)(gong)作臺尺寸應保(bao)證工(gong)(gong)件(jian)在(zai)其上面能順利裝夾工(gong)(gong)件(jian)，加(jia)工(gong)(gong)尺寸則(ze)必(bi)須在(zai)各(ge)坐(zuo)標行程內，此外還要考慮換刀空間和各(ge)坐(zuo)標干涉區的(de)(de)限(xian)制。 

機床精(jing)(jing)(jing)度的選定(ding)(ding)的精(jing)(jing)(jing)度分類為普(pu)通型和精(jing)(jing)(jing)密(mi)型，其(qi)主(zhu)要精(jing)(jing)(jing)度項(xiang)目見下表：立(li)式(shi)加工(gong)中心主(zhu)要精(jing)(jing)(jing)度項(xiang)目精(jing)(jing)(jing)度項(xiang)目普(pu)通型(mm)精(jing)(jing)(jing)密(mi)型(mm)直線定(ding)(ding)位精(jing)(jing)(jing)度±0.01/全程(cheng)(cheng)±0.005/全程(cheng)(cheng)重(zhong)復定(ding)(ding)位精(jing)(jing)(jing)度±0.006±0.002。