在生產過(guo)(guo)(guo)程(cheng)(cheng)中，那(nei)些與有原材(cai)料轉變(bian)為產品直(zhi)接相關的(de)過(guo)(guo)(guo)程(cheng)(cheng)稱為工(gong)(gong)(gong)藝(yi)過(guo)(guo)(guo)程(cheng)(cheng)。它包括(kuo)毛坯制造、零件加工(gong)(gong)(gong)、熱處理、質量檢驗(yan)和(he)機器裝配等。而為保證工(gong)(gong)(gong)藝(yi)過(guo)(guo)(guo)程(cheng)(cheng)正(zheng)常進行所需要的(de)刀具(ju)、夾具(ju)制造，機床調整維修等則屬(shu)于輔助過(guo)(guo)(guo)程(cheng)(cheng)。在工(gong)(gong)(gong)藝(yi)過(guo)(guo)(guo)程(cheng)(cheng)中，以機械(xie)加工(gong)(gong)(gong)方法按一定(ding)順序逐步(bu)地改變(bian)毛坯形狀、尺寸、相對位置和(he)性能等，直(zhi)至成(cheng)為合格零件的(de)那(nei)部分過(guo)(guo)(guo)程(cheng)(cheng)稱為機械(xie)加工(gong)(gong)(gong)工(gong)(gong)(gong)藝(yi)過(guo)(guo)(guo)程(cheng)(cheng)。技術人員根據產品數量、設備條件和(he)工(gong)(gong)(gong)人素質等情況，確定(ding)采(cai)用的(de)工(gong)(gong)(gong)藝(yi)過(guo)(guo)(guo)程(cheng)(cheng)，并(bing)將有關內容寫(xie)成(cheng)工(gong)(gong)(gong)藝(yi)文(wen)件，這種文(wen)件就稱工(gong)(gong)(gong)藝(yi)規程(cheng)(cheng)。

為了便于工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)藝(yi)規程(cheng)(cheng)的(de)(de)(de)編制、執(zhi)行和生產組(zu)織管理，需要(yao)把工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)藝(yi)過程(cheng)(cheng)劃分(fen)為不同(tong)層次的(de)(de)(de)單元。它(ta)(ta)們是(shi)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序、安裝、工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位、工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)步(bu)和走刀(dao)。其中(zhong)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序是(shi)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)藝(yi)過程(cheng)(cheng)中(zhong)的(de)(de)(de)基(ji)本單元。零件的(de)(de)(de)機(ji)(ji)械加工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)藝(yi)過程(cheng)(cheng)由若干個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序組(zu)成。在(zai)(zai)一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序中(zhong)可(ke)(ke)(ke)能包含(han)有(you)一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)或(huo)幾(ji)(ji)個(ge)(ge)(ge)安裝，每(mei)一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)安裝可(ke)(ke)(ke)能包含(han)一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)或(huo)幾(ji)(ji)個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位，每(mei)一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位可(ke)(ke)(ke)能包含(han)一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)或(huo)幾(ji)(ji)個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)步(bu)，每(mei)一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)步(bu)可(ke)(ke)(ke)能包括一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)或(huo)幾(ji)(ji)個(ge)(ge)(ge)走刀(dao)。（1）工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序　一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)或(huo)一(yi)(yi)(yi)(yi)(yi)組(zu)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)人，在(zai)(zai)一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)作地或(huo)一(yi)(yi)(yi)(yi)(yi)臺(tai)機(ji)(ji)床(chuang)上對(dui)(dui)一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)或(huo)同(tong)時對(dui)(dui)幾(ji)(ji)個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件連(lian)續完成的(de)(de)(de)那一(yi)(yi)(yi)(yi)(yi)部(bu)分(fen)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)藝(yi)過程(cheng)(cheng)稱(cheng)為工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序。劃分(fen)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序的(de)(de)(de)依(yi)據是(shi)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)作地點是(shi)否變化和工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)作過程(cheng)(cheng)是(shi)否連(lian)續。例如(ru)，在(zai)(zai)車床(chuang)上加工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)一(yi)(yi)(yi)(yi)(yi)批軸(zhou)，既(ji)可(ke)(ke)(ke)以對(dui)(dui)每(mei)一(yi)(yi)(yi)(yi)(yi)根軸(zhou)連(lian)續地進行粗加工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)和精加工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)，也(ye)可(ke)(ke)(ke)以先(xian)對(dui)(dui)整批軸(zhou)進行粗加工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)，然后再依(yi)次對(dui)(dui)它(ta)(ta)們進行精加工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)。在(zai)(zai)第(di)一(yi)(yi)(yi)(yi)(yi)種(zhong)情形(xing)(xing)下，加工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)只(zhi)包括一(yi)(yi)(yi)(yi)(yi)個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序；而(er)在(zai)(zai)第(di)二(er)種(zhong)情形(xing)(xing)下，由于加工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)過程(cheng)(cheng)的(de)(de)(de)連(lian)續性(xing)中(zhong)斷，雖然加工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)是(shi)在(zai)(zai)同(tong)一(yi)(yi)(yi)(yi)(yi)臺(tai)機(ji)(ji)床(chuang)上進行的(de)(de)(de)，但卻成為兩個(ge)(ge)(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序。

工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序(xu)(xu)(xu)是(shi)(shi)組成(cheng)(cheng)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)藝過(guo)(guo)程的(de)(de)(de)(de)基(ji)本單(dan)元，也是(shi)(shi)生產計劃的(de)(de)(de)(de)基(ji)本單(dan)元。（2）安(an)裝(zhuang)(zhuang)(zhuang)　在(zai)(zai)機(ji)(ji)械加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序(xu)(xu)(xu)中，使(shi)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件(jian)(jian)(jian)在(zai)(zai)機(ji)(ji)床(chuang)上(shang)(shang)或在(zai)(zai)夾具(ju)中占據某一(yi)(yi)(yi)正確位(wei)(wei)置(zhi)并被(bei)夾緊的(de)(de)(de)(de)過(guo)(guo)程，稱為(wei)裝(zhuang)(zhuang)(zhuang)夾。有時(shi)，工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件(jian)(jian)(jian)在(zai)(zai)機(ji)(ji)床(chuang)上(shang)(shang)需(xu)經過(guo)(guo)多次(ci)(ci)裝(zhuang)(zhuang)(zhuang)夾才(cai)能完(wan)成(cheng)(cheng)一(yi)(yi)(yi)個(ge)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序(xu)(xu)(xu)的(de)(de)(de)(de)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)作(zuo)內容(rong)。安(an)裝(zhuang)(zhuang)(zhuang)是(shi)(shi)指工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件(jian)(jian)(jian)經過(guo)(guo)一(yi)(yi)(yi)次(ci)(ci)裝(zhuang)(zhuang)(zhuang)夾后所(suo)完(wan)成(cheng)(cheng)的(de)(de)(de)(de)那(nei)部(bu)(bu)(bu)分(fen)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序(xu)(xu)(xu)內容(rong)。例如，在(zai)(zai)車床(chuang)上(shang)(shang)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)軸，先(xian)從(cong)一(yi)(yi)(yi)端加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)出部(bu)(bu)(bu)分(fen)表面(mian)(mian)，然后調頭再(zai)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)另(ling)一(yi)(yi)(yi)端，這時(shi)的(de)(de)(de)(de)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序(xu)(xu)(xu)內容(rong)就(jiu)包括兩(liang)個(ge)安(an)裝(zhuang)(zhuang)(zhuang)。（3）工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位(wei)(wei)　采(cai)用轉(zhuan)位(wei)(wei)（或移位(wei)(wei)）夾具(ju)、回轉(zhuan)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)作(zuo)臺或在(zai)(zai)多軸機(ji)(ji)床(chuang)上(shang)(shang)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)時(shi)，工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件(jian)(jian)(jian)在(zai)(zai)機(ji)(ji)床(chuang)上(shang)(shang)一(yi)(yi)(yi)次(ci)(ci)裝(zhuang)(zhuang)(zhuang)夾后，要經過(guo)(guo)若干個(ge)位(wei)(wei)置(zhi)依次(ci)(ci)進行(xing)(xing)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)，工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件(jian)(jian)(jian)在(zai)(zai)機(ji)(ji)床(chuang)上(shang)(shang)所(suo)占據的(de)(de)(de)(de)每(mei)一(yi)(yi)(yi)個(ge)位(wei)(wei)置(zhi)上(shang)(shang)所(suo)完(wan)成(cheng)(cheng)的(de)(de)(de)(de)那(nei)一(yi)(yi)(yi)部(bu)(bu)(bu)分(fen)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序(xu)(xu)(xu)就(jiu)稱為(wei)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位(wei)(wei)。簡單(dan)來說，工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件(jian)(jian)(jian)相對(dui)于機(ji)(ji)床(chuang)或刀具(ju)每(mei)占據一(yi)(yi)(yi)個(ge)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位(wei)(wei)置(zhi)所(suo)完(wan)成(cheng)(cheng)的(de)(de)(de)(de)那(nei)部(bu)(bu)(bu)分(fen)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序(xu)(xu)(xu)內容(rong)，稱為(wei)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位(wei)(wei)。為(wei)了減少因多次(ci)(ci)裝(zhuang)(zhuang)(zhuang)夾而帶來的(de)(de)(de)(de)裝(zhuang)(zhuang)(zhuang)夾誤差和時(shi)間損失，常采(cai)用各種回轉(zhuan)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)作(zuo)臺、回轉(zhuan)夾具(ju)或移動夾具(ju)，使(shi)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件(jian)(jian)(jian)在(zai)(zai)一(yi)(yi)(yi)次(ci)(ci)裝(zhuang)(zhuang)(zhuang)夾中，先(xian)后處于幾(ji)個(ge)不(bu)同(tong)的(de)(de)(de)(de)位(wei)(wei)置(zhi)進行(xing)(xing)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)。圖1-1是(shi)(shi)在(zai)(zai)一(yi)(yi)(yi)臺三(san)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位(wei)(wei)回轉(zhuan)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)作(zuo)臺機(ji)(ji)床(chuang)上(shang)(shang)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)軸承蓋(gai)螺(luo)釘孔(kong)(kong)的(de)(de)(de)(de)示意圖。操作(zuo)者在(zai)(zai)上(shang)(shang)下(xia)料工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位(wei)(wei)Ⅰ處裝(zhuang)(zhuang)(zhuang)上(shang)(shang)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件(jian)(jian)(jian)，當該工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)件(jian)(jian)(jian)依次(ci)(ci)通過(guo)(guo)鉆孔(kong)(kong)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位(wei)(wei)Ⅱ、擴孔(kong)(kong)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位(wei)(wei)Ⅲ后，即可在(zai)(zai)一(yi)(yi)(yi)次(ci)(ci)裝(zhuang)(zhuang)(zhuang)夾后把四個(ge)階(jie)梯孔(kong)(kong)在(zai)(zai)兩(liang)個(ge)位(wei)(wei)置(zhi)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)完(wan)畢。這樣，既減少了裝(zhuang)(zhuang)(zhuang)夾次(ci)(ci)數，又因各工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)位(wei)(wei)的(de)(de)(de)(de)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)與(yu)裝(zhuang)(zhuang)(zhuang)卸(xie)是(shi)(shi)同(tong)時(shi)進行(xing)(xing)的(de)(de)(de)(de)，從(cong)而節(jie)約安(an)裝(zhuang)(zhuang)(zhuang)時(shi)間使(shi)生產率可以大提高(gao)。 （4）工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)步(bu)　在(zai)(zai)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)表面(mian)(mian)不(bu)變(bian)，加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)具(ju)不(bu)變(bian)的(de)(de)(de)(de)條件(jian)(jian)(jian)下(xia)，所(suo)連(lian)續完(wan)成(cheng)(cheng)的(de)(de)(de)(de)那(nei)一(yi)(yi)(yi)部(bu)(bu)(bu)分(fen)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)序(xu)(xu)(xu)內容(rong)稱為(wei)工(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)(gong)步(bu)。生產中也常稱為(wei)“進給(gei)”。

整(zheng)個(ge)(ge)(ge)(ge)工(gong)(gong)藝過程由若干(gan)個(ge)(ge)(ge)(ge)工(gong)(gong)序組(zu)成(cheng)。每(mei)一(yi)個(ge)(ge)(ge)(ge)工(gong)(gong)序可包(bao)括一(yi)個(ge)(ge)(ge)(ge)工(gong)(gong)步(bu)(bu)(bu)或幾個(ge)(ge)(ge)(ge)工(gong)(gong)步(bu)(bu)(bu)。每(mei)一(yi)個(ge)(ge)(ge)(ge)工(gong)(gong)步(bu)(bu)(bu)通常(chang)包(bao)括一(yi)個(ge)(ge)(ge)(ge)工(gong)(gong)作行程，也(ye)可包(bao)括幾個(ge)(ge)(ge)(ge)工(gong)(gong)作行程。為了提(ti)高生產(chan)率，用幾把刀(dao)(dao)具(ju)同時加(jia)(jia)工(gong)(gong)幾個(ge)(ge)(ge)(ge)加(jia)(jia)工(gong)(gong)表(biao)面的(de)工(gong)(gong)步(bu)(bu)(bu)，稱為復合工(gong)(gong)步(bu)(bu)(bu)，也(ye)可以(yi)看(kan)作一(yi)個(ge)(ge)(ge)(ge)工(gong)(gong)步(bu)(bu)(bu)，例(li)如，組(zu)合鉆床加(jia)(jia)工(gong)(gong)多孔箱體孔。（5）走(zou)刀(dao)(dao)　加(jia)(jia)工(gong)(gong)刀(dao)(dao)具(ju)在(zai)加(jia)(jia)工(gong)(gong)表(biao)面上(shang)加(jia)(jia)工(gong)(gong)一(yi)次(ci)所(suo)完(wan)成(cheng)的(de)工(gong)(gong)步(bu)(bu)(bu)部(bu)分稱為走(zou)刀(dao)(dao)。例(li)如軸(zhou)類零(ling)件如果要切(qie)去的(de)金屬層(ceng)很厚，則需分幾次(ci)切(qie)削，這時每(mei)切(qie)削一(yi)次(ci)就稱為一(yi)次(ci)走(zou)刀(dao)(dao)。因此(ci)在(zai)切(qie)削速度(du)和進給量(liang)不變的(de)前提(ti)下(xia)刀(dao)(dao)具(ju)完(wan)成(cheng)一(yi)次(ci)進給運動稱為一(yi)次(ci)走(zou)刀(dao)(dao)。