目錄:行(xing)業動態發布時(shi)間:2018-07-23 12:06:55點擊率:
加工中心適宜于加工復(fu)雜(za)、工序多(duo)(duo)、要求較(jiao)高、需用(yong)多(duo)(duo)種類(lei)型的(de)普(pu)通機床(chuang)和(he)(he)眾多(duo)(duo)刀具(ju)夾具(ju),且經多(duo)(duo)次(ci)裝夾和(he)(he)調整才(cai)能完(wan)成加工的(de)零件(jian)。其(qi)加工的(de)主要對(dui)象有箱體(ti)類(lei)零件(jian)、復(fu)雜(za)曲面、異形(xing)件(jian)、盤套板類(lei)零件(jian)和(he)(he)特殊(shu)加工等五類(lei)。
(1)箱體類(lei)零件
箱(xiang)(xiang)體類(lei)零(ling)件(jian)一(yi)般(ban)是指具有(you)一(yi)個(ge)以上(shang)孔(kong)系,內部有(you)型腔,在長(chang)、寬、高(gao)(gao)方向有(you)一(yi)定(ding)比例的(de)零(ling)件(jian)。這類(lei)零(ling)件(jian)在機床、汽車(che)、飛(fei)機制造等(deng)(deng)行業用(yong)的(de)較(jiao)(jiao)多(duo)(duo)(duo)。箱(xiang)(xiang)體類(lei)零(ling)件(jian)一(yi)般(ban)都(dou)需要進行多(duo)(duo)(duo)工(gong)(gong)(gong)位(wei)孔(kong)系及(ji)平面加工(gong)(gong)(gong),公差要求較(jiao)(jiao)高(gao)(gao),特別是形位(wei)公差要求較(jiao)(jiao)為嚴(yan)格,通常要經過銑(xian)、鉆、擴、鏜(tang)、鉸、锪(huo),攻絲等(deng)(deng)工(gong)(gong)(gong)序,需要刀具較(jiao)(jiao)多(duo)(duo)(duo),在普通機床上(shang)加工(gong)(gong)(gong)難度(du)大,工(gong)(gong)(gong)裝(zhuang)套(tao)數多(duo)(duo)(duo),費用(yong)高(gao)(gao),加工(gong)(gong)(gong)周(zhou)期長(chang),需多(duo)(duo)(duo)次(ci)裝(zhuang)夾(jia)、找正,手工(gong)(gong)(gong)測量次(ci)數多(duo)(duo)(duo),加工(gong)(gong)(gong)時必須頻(pin)繁地(di)更(geng)換刀具,工(gong)(gong)(gong)藝難以制定(ding),更(geng)重要的(de)是精度(du)難以保證。
加工(gong)(gong)箱體(ti)類零(ling)件(jian)的(de)加工(gong)(gong)中心(xin)(xin),當(dang)(dang)加工(gong)(gong)工(gong)(gong)位(wei)較多,需工(gong)(gong)作臺多次(ci)旋轉角度才能完成的(de)零(ling)件(jian),一般(ban)選臥式(shi)鏜(tang)銑類加工(gong)(gong)中心(xin)(xin)。當(dang)(dang)加工(gong)(gong)的(de)工(gong)(gong)位(wei)較少,且跨距不大時,可選立式(shi)加工(gong)(gong)中心(xin)(xin),從一端(duan)進(jin)行加工(gong)(gong)。
(2)復雜曲面
復(fu)雜曲(qu)(qu)面(mian)在機械(xie)制造(zao)業,特別是航(hang)(hang)天航(hang)(hang)空工業中占有特殊重要的地位。復(fu)雜曲(qu)(qu)面(mian)采(cai)用(yong)普通機加工方法(fa)(fa)是難以甚至無法(fa)(fa)完(wan)成的。在我國,傳統的方法(fa)(fa)是采(cai)用(yong)精密鑄造(zao),可想而知其精度是低的。復(fu)雜曲(qu)(qu)面(mian)類零(ling)件(jian)如(ru):各(ge)種(zhong)(zhong)葉(xie)輪(lun),導(dao)風輪(lun),球面(mian),各(ge)種(zhong)(zhong)曲(qu)(qu)面(mian)成形模(mo)具,螺旋槳以及水下(xia)航(hang)(hang)行器的推進(jin)器,以及一些其它(ta)形狀的自由曲(qu)(qu)面(mian)。這類零(ling)件(jian)均可用(yong)加工中心(xin)進(jin)行加工。比較典型的下(xia)面(mian)幾(ji)種(zhong)(zhong):
①凸輪、凸輪機構
作(zuo)為(wei)機械式信息貯存(cun)與傳(chuan)遞的(de)基(ji)本(ben)元件(jian),被廣泛(fan)地應用于各種(zhong)自動機械中,這類零件(jian)有各種(zhong)曲線的(de)盤形凸(tu)輪(lun)(lun),圓柱凸(tu)輪(lun)(lun)、圓錐凸(tu)輪(lun)(lun)、桶形凸(tu)輪(lun)(lun)、端面凸(tu)輪(lun)(lun)等。加工這類零件(jian)可根據凸(tu)輪(lun)(lun)的(de)復雜程度選(xuan)用三軸(zhou)、四軸(zhou)聯(lian)動或選(xuan)用五(wu)軸(zhou)聯(lian)動的(de)加工中心。
②整體葉輪(lun)類(lei)
這(zhe)類零件常見于(yu)(yu)航空(kong)發(fa)動機(ji)的(de)壓氣機(ji),制(zhi)氧設備的(de)膨脹機(ji),單(dan)螺(luo)桿空(kong)氣壓縮(suo)機(ji)等,對于(yu)(yu)這(zhe)樣的(de)型面,可采(cai)用四軸(zhou)以上(shang)聯動的(de)加(jia)工中心(xin)才(cai)能(neng)完成(cheng)。
③模具類
如注塑(su)模(mo)(mo)(mo)(mo)(mo)具、橡膠(jiao)模(mo)(mo)(mo)(mo)(mo)具、真空(kong)成(cheng)形吸(xi)塑(su)模(mo)(mo)(mo)(mo)(mo)具、電冰箱發泡(pao)模(mo)(mo)(mo)(mo)(mo)具、壓力鑄造模(mo)(mo)(mo)(mo)(mo)具,精(jing)密鑄造模(mo)(mo)(mo)(mo)(mo)具等。采用加(jia)(jia)工(gong)中(zhong)心加(jia)(jia)工(gong)模(mo)(mo)(mo)(mo)(mo)具,由于(yu)工(gong)序高度(du)集中(zhong),動模(mo)(mo)(mo)(mo)(mo)、靜模(mo)(mo)(mo)(mo)(mo)等關鍵件的精(jing)加(jia)(jia)工(gong)基(ji)本上是在一次安裝中(zhong)完成(cheng)全部機加(jia)(jia)工(gong)內容,可減(jian)少尺寸累計(ji)誤差,減(jian)少修配工(gong)作(zuo)量。同時,模(mo)(mo)(mo)(mo)(mo)具的可復制性(xing)強,互換性(xing)好(hao)。機械加(jia)(jia)工(gong)殘留給鉗工(gong)的工(gong)作(zuo)量少,凡(fan)刀具可及之處,盡可能由機械加(jia)(jia)工(gong)完成(cheng),這樣使模(mo)(mo)(mo)(mo)(mo)具鉗工(gong)的工(gong)作(zuo)量主要在于(yu)拋光。
④球面
可采用加工中心(xin)銑(xian)削(xue)。三軸(zhou)銑(xian)削(xue)只能用球(qiu)頭銑(xian)刀作(zuo)逼近(jin)加工,效(xiao)率較低,五軸(zhou)銑(xian)削(xue)可采用端銑(xian)刀作(zuo)包絡面(mian)來(lai)逼近(jin)球(qiu)面(mian)。復雜曲面(mian)用加工中心(xin)加工時,編程工作(zuo)量較大,大多(duo)數(shu)要(yao)有自(zi)動編程技術。
(3)異形件
異形(xing)(xing)件是外形(xing)(xing)不(bu)規則的(de)(de)零(ling)(ling)件,大都(dou)需要(yao)點(dian)、線(xian)、面多工(gong)(gong)位(wei)混合(he)加(jia)(jia)(jia)工(gong)(gong)。異形(xing)(xing)件的(de)(de)剛性(xing)一般較差,夾壓(ya)變形(xing)(xing)難以控制,加(jia)(jia)(jia)工(gong)(gong)精度也難以保證(zheng),甚至某些零(ling)(ling)件的(de)(de)有的(de)(de)加(jia)(jia)(jia)工(gong)(gong)部位(wei)用(yong)普通機(ji)床難以完成。用(yong)加(jia)(jia)(jia)工(gong)(gong)中(zhong)心加(jia)(jia)(jia)工(gong)(gong)時(shi)應采用(yong)合(he)理的(de)(de)工(gong)(gong)藝(yi)措施,一次或(huo)二次裝夾,利用(yong)加(jia)(jia)(jia)工(gong)(gong)中(zhong)心多工(gong)(gong)位(wei)點(dian)、線(xian)、面混合(he)加(jia)(jia)(jia)工(gong)(gong)的(de)(de)特點(dian),完成多道工(gong)(gong)序(xu)或(huo)全部的(de)(de)工(gong)(gong)序(xu)內容。
(4)盤、套、板類零件
帶有(you)(you)(you)鍵槽,或(huo)(huo)徑向(xiang)(xiang)孔(kong),或(huo)(huo)端面有(you)(you)(you)分布的孔(kong)系,曲面的盤套或(huo)(huo)軸類零(ling)件(jian)(jian),如(ru)帶法蘭的軸套,帶鍵槽或(huo)(huo)方頭的軸類零(ling)件(jian)(jian)等,還有(you)(you)(you)具有(you)(you)(you)較(jiao)多孔(kong)加工(gong)的板類零(ling)件(jian)(jian),如(ru)各種(zhong)電機蓋等。端面有(you)(you)(you)分布孔(kong)系、曲面的盤類零(ling)件(jian)(jian)宜選擇立式(shi)加工(gong)中心,有(you)(you)(you)徑向(xiang)(xiang)孔(kong)的可選臥(wo)式(shi)加工(gong)中心。
(5)特殊加(jia)工(gong)
在(zai)熟練(lian)掌(zhang)握(wo)了加(jia)工(gong)中(zhong)心(xin)的功能之后,配合(he)一定的工(gong)裝(zhuang)和專用(yong)工(gong)具(ju),利用(yong)加(jia)工(gong)中(zhong)心(xin)可(ke)完成(cheng)一些(xie)特殊的工(gong)藝(yi)工(gong)作,如在(zai)金屬表(biao)面(mian)上(shang)刻(ke)字、刻(ke)線(xian)(xian)、刻(ke)圖案;在(zai)加(jia)工(gong)中(zhong)心(xin)的主軸上(shang)裝(zhuang)上(shang)高(gao)頻電火花電源,可(ke)對金屬表(biao)面(mian)進行線(xian)(xian)掃(sao)描表(biao)面(mian)淬火;用(yong)加(jia)工(gong)中(zhong)心(xin)裝(zhuang)上(shang)高(gao)速磨(mo)頭,可(ke)實現小模數(shu)漸開線(xian)(xian)圓錐齒(chi)輪磨(mo)削及各種曲(qu)線(xian)(xian)、曲(qu)面(mian)的磨(mo)削等(deng)。