相(xiang)對于數控加(jia)(jia)(jia)工(gong)中心的(de)表面(mian)加(jia)(jia)(jia)工(gong)，孔加(jia)(jia)(jia)工(gong)要(yao)復雜的(de)多，加(jia)(jia)(jia)工(gong)孔也要(yao)比加(jia)(jia)(jia)工(gong)內外表面(mian)更(geng)為困(kun)難。雖然如此(ci)，鉆孔加(jia)(jia)(jia)工(gong)依然是數控加(jia)(jia)(jia)工(gong)中心最為常用的(de)加(jia)(jia)(jia)工(gong)方(fang)式之(zhi)一(yi)。采購(gou)加(jia)(jia)(jia)工(gong)中心作為加(jia)(jia)(jia)工(gong)設(she)備的(de)話，孔加(jia)(jia)(jia)工(gong)的(de)方(fang)法技(ji)巧一(yi)定要(yao)爛熟于心。

數控加工中心常見的孔加工方式主要有：鉆孔、絞孔、鏜孔、拉孔等，其中鉆孔和鉸孔最為常用，這兩種工藝幾乎每個制造車間，生產廠家都可以應用到。以小型高精的vmc650加工中心為(wei)例，鉆孔、鉸孔的工(gong)藝(yi)技巧(qiao)需要(yao)重點(dian)掌握。

鉆孔

鉆(zhan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)之所以最為常用(yong)，那(nei)是(shi)(shi)因(yin)為這(zhe)是(shi)(shi)在(zai)實心(xin)材料上加(jia)工(gong)(gong)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)的(de)(de)第一道(dao)工(gong)(gong)序。鉆(zhan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)加(jia)工(gong)(gong)有(you)兩種方(fang)式：一種是(shi)(shi)鉆(zhan)頭旋轉；另一種是(shi)(shi)工(gong)(gong)件旋轉。鉆(zhan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)直(zhi)(zhi)徑(jing)一般小于80mm，精度(du)和準確(que)度(du)要求較高。而兩種鉆(zhan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)方(fang)式產生的(de)(de)誤(wu)差(cha)是(shi)(shi)不(bu)(bu)相同的(de)(de)。在(zai)鉆(zhan)頭旋轉的(de)(de)鉆(zhan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)方(fang)式中(zhong)，由于切削刃不(bu)(bu)對稱(cheng)和鉆(zhan)頭剛(gang)性(xing)不(bu)(bu)足而使鉆(zhan)頭引偏(pian)時，被加(jia)工(gong)(gong)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)的(de)(de)中(zhong)心(xin)線會發生偏(pian)斜或不(bu)(bu)直(zhi)(zhi)，但孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)徑(jing)基本(ben)不(bu)(bu)變；而在(zai)工(gong)(gong)件旋轉的(de)(de)鉆(zhan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)方(fang)式中(zhong)則相反(fan)，鉆(zhan)頭引偏(pian)會引起孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)徑(jing)變化，而孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)中(zhong)心(xin)線仍然是(shi)(shi)直(zhi)(zhi)的(de)(de)。

常用鉆孔刀具有：麻(ma)花(hua)鉆、中(zhong)心鉆、深孔鉆等，VMC850加(jia)工中(zhong)心最配備的是麻(ma)花(hua)鉆。

鉸孔(kong)

鉸孔是孔的精加工方(fang)法之(zhi)一(yi)，在生產中應用很廣。

鉸(jiao)(jiao)孔余(yu)量(liang)(liang)對鉸(jiao)(jiao)孔質量(liang)(liang)的(de)(de)(de)影響很(hen)大(da)，余(yu)量(liang)(liang)太大(da)，鉸(jiao)(jiao)刀的(de)(de)(de)負(fu)荷大(da)，切削刃很(hen)快(kuai)被磨鈍(dun)，不(bu)易(yi)獲(huo)得光(guang)潔的(de)(de)(de)加工(gong)表面，尺寸公差也不(bu)易(yi)保證(zheng)；余(yu)量(liang)(liang)太小(xiao)，不(bu)能去掉上工(gong)序留下(xia)的(de)(de)(de)刀痕，自然也就沒有改善孔加工(gong)質量(liang)(liang)的(de)(de)(de)作用。一般(ban)粗鉸(jiao)(jiao)余(yu)量(liang)(liang)取為(wei)0.35~0.15mm，精鉸(jiao)(jiao)取為(wei)01.5~0.05mm。

鉸(jiao)孔(kong)(kong)(kong)時必須用適(shi)當的切削液進行冷卻(que)、潤滑和清洗，以防止產(chan)生積屑瘤并及(ji)時清除(chu)切屑。與磨(mo)孔(kong)(kong)(kong)和鏜孔(kong)(kong)(kong)相比，鉸(jiao)孔(kong)(kong)(kong)生產(chan)率高(gao)，容易保證孔(kong)(kong)(kong)的精(jing)度；但(dan)(dan)鉸(jiao)孔(kong)(kong)(kong)不能校正孔(kong)(kong)(kong)軸線(xian)的位置誤差，孔(kong)(kong)(kong)的位置精(jing)度應由前工(gong)序保證。VMC850加(jia)工(gong)中心(xin)具有完備的切削冷卻(que)系統可以完美解決鉸(jiao)孔(kong)(kong)(kong)工(gong)藝，但(dan)(dan)是鉸(jiao)孔(kong)(kong)(kong)不宜加(jia)工(gong)階梯孔(kong)(kong)(kong)和盲(mang)孔(kong)(kong)(kong)。