機械(xie)加工(gong)是指通過一種機械(xie)設備對工(gong)件的外形尺寸或性能(neng)進行改(gai)變的過程。按加工(gong)方(fang)式上的差別可分(fen)為切削(xue)加工(gong)和壓力加工(gong)。

在生(sheng)產過(guo)(guo)(guo)程(cheng)(cheng)中，凡是改變生(sheng)產對象的形狀、尺寸、位置(zhi)和性(xing)質(zhi)等，使其成(cheng)(cheng)(cheng)為成(cheng)(cheng)(cheng)品(pin)或(huo)者半成(cheng)(cheng)(cheng)品(pin)的過(guo)(guo)(guo)程(cheng)(cheng)稱(cheng)為工(gong)(gong)(gong)藝(yi)(yi)過(guo)(guo)(guo)程(cheng)(cheng)。它是生(sheng)產過(guo)(guo)(guo)程(cheng)(cheng)的主要部分(fen)。工(gong)(gong)(gong)藝(yi)(yi)過(guo)(guo)(guo)程(cheng)(cheng)又可分(fen)為鑄造、鍛造、沖壓(ya)、焊接、機(ji)械(xie)加(jia)(jia)工(gong)(gong)(gong)、裝配等工(gong)(gong)(gong)藝(yi)(yi)過(guo)(guo)(guo)程(cheng)(cheng)，機(ji)械(xie)制造工(gong)(gong)(gong)藝(yi)(yi)過(guo)(guo)(guo)程(cheng)(cheng)一(yi)般是指零件的機(ji)械(xie)加(jia)(jia)工(gong)(gong)(gong)工(gong)(gong)(gong)藝(yi)(yi)過(guo)(guo)(guo)程(cheng)(cheng)和機(ji)器(qi)的裝配工(gong)(gong)(gong)藝(yi)(yi)過(guo)(guo)(guo)程(cheng)(cheng)的總和，其他(ta)過(guo)(guo)(guo)程(cheng)(cheng)則稱(cheng)為輔助過(guo)(guo)(guo)程(cheng)(cheng)，例如運輸(shu)、保管、動力供應、設備(bei)維(wei)修等。工(gong)(gong)(gong)藝(yi)(yi)過(guo)(guo)(guo)程(cheng)(cheng)又是由(you)一(yi)個或(huo)若(ruo)干個順序(xu)排列(lie)的工(gong)(gong)(gong)序(xu)組(zu)成(cheng)(cheng)(cheng)的，一(yi)個工(gong)(gong)(gong)序(xu)由(you)有若(ruo)干個工(gong)(gong)(gong)步組(zu)成(cheng)(cheng)(cheng)。