（1）分(fen)析(xi)零(ling)件(jian)(jian)圖(tu)和(he)產品(pin)裝(zhuang)配(pei)圖(tu)設計工(gong)藝規程(cheng)時(shi)，首(shou)先應分(fen)析(xi)零(ling)件(jian)(jian)圖(tu)和(he)該(gai)零(ling)件(jian)(jian)所在部(bu)件(jian)(jian)或(huo)總成的裝(zhuang)配(pei)圖(tu)，了(le)解該(gai)零(ling)件(jian)(jian)在部(bu)件(jian)(jian)或(huo)總成中的位置和(he)功(gong)用(yong)以及部(bu)件(jian)(jian)或(huo)總成對(dui)該(gai)零(ling)件(jian)(jian)提出的技術(shu)(shu)要求，分(fen)析(xi)其主要技術(shu)(shu)關(guan)鍵和(he)應相應采取的工(gong)藝措(cuo)施。
（2）對零件圖和裝配圖進行工藝審查審查圖紙上(shang)的(de)視圖、尺寸公差(cha)和(he)技術(shu)要求是否正確、統一、完整，對零件設計的(de)結構(gou)工藝性進行(xing)評價(jia)（評價(jia)方(fang)法及要領(ling)參(can)見(jian)本章第六節），如發(fa)現有不合理(li)之(zhi)處(chu)應及時提(ti)出，并同有關設計人員商討圖紙修改方(fang)案(an)，報主管(guan)領(ling)導審批。
（3）由產品的年生(sheng)產綱領和產品自身(shen)特(te)性研究確定零件生(sheng)產類型（參見第(di)一章(zhang)第(di)三(san)節）。
（4）確定毛坯提高毛坯制(zhi)造質量，可以減(jian)少機械(xie)(xie)加(jia)工(gong)(gong)勞動量，降(jiang)低(di)機械(xie)(xie)加(jia)工(gong)(gong)成(cheng)本，但同(tong)時可能(neng)會(hui)增加(jia)毛坯的(de)制(zhi)造(zao)(zao)(zao)成(cheng)本，須根據零件生(sheng)產類型和(he)毛坯制(zhi)造(zao)(zao)(zao)的(de)生(sheng)產條件確定毛坯制(zhi)造(zao)(zao)(zao)方(fang)(fang)法。應當指(zhi)出(chu)，我國機械(xie)(xie)制(zhi)造(zao)(zao)(zao)工(gong)(gong)廠的(de)材料(liao)利用率(lv)較低(di)，只要有可能(neng)，應提倡采用精密(mi)鑄造(zao)(zao)(zao)、精密(mi)鍛造(zao)(zao)(zao)、冷軋(ya)、冷擠壓、粉末冶金等先進的(de)毛坯制(zhi)造(zao)(zao)(zao)方(fang)(fang)法。材料(liao)利用系數是衡量工(gong)(gong)藝規程設(she)計是否(fou)合理的(de)一個重要參(can)數。
（5）擬(ni)訂工(gong)(gong)(gong)(gong)藝(yi)(yi)路(lu)線其主要內(nei)容包括：選(xuan)擇(ze)定(ding)(ding)位基準，確定(ding)(ding)各(ge)加(jia)工(gong)(gong)(gong)(gong)表面的(de)加(jia)工(gong)(gong)(gong)(gong)方(fang)法，劃分(fen)加(jia)工(gong)(gong)(gong)(gong)階段，確定(ding)(ding)工(gong)(gong)(gong)(gong)序(xu)集中和(he)分(fen)散程(cheng)度，確定(ding)(ding)工(gong)(gong)(gong)(gong)序(xu)順序(xu)等(deng)。在(zai)擬(ni)定(ding)(ding)工(gong)(gong)(gong)(gong)藝(yi)(yi)路(lu)線時，須同時提出幾種可能的(de)加(jia)工(gong)(gong)(gong)(gong)方(fang)案，然后通(tong)過技術和(he)經(jing)濟(ji)的(de)對(dui)比分(fen)析，最后確定(ding)(ding)一種最為合理的(de)工(gong)(gong)(gong)(gong)藝(yi)(yi)方(fang)案。
（6）確(que)定(ding)各(ge)工(gong)(gong)序所用機床設(she)(she)備和工(gong)(gong)藝(yi)裝備（含刀具(ju)、夾具(ju)、量具(ju)、輔具(ju)等(deng)），對(dui)需要改裝或重新設(she)(she)計的(de)專(zhuan)用工(gong)(gong)藝(yi)裝備要提出設(she)(she)計任(ren)務(wu)書。
（7）確定各工序(xu)的加工余量(liang)，計算工序(xu)尺寸(cun)及(ji)公差。
（8）確定各工序的技術要求及檢驗方法。
（9）確定各(ge)工序(xu)的切削用量和工時定額。
（10）編制工藝文件。
擬訂工藝(yi)路線是(shi)設計工藝(yi)規程最為關鍵的(de)一步，需順序(xu)完成以下幾(ji)個方面的(de)工作。
（一）選擇(ze)定位基準
在(zai)工(gong)藝規程(cheng)設(she)計中，正確選(xuan)擇(ze)定(ding)位(wei)基(ji)(ji)準(zhun)，對(dui)保(bao)證零(ling)件(jian)(jian)技術(shu)要(yao)求、確定(ding)加工(gong)先后順序(xu)有著至關(guan)重要(yao)的影響。定(ding)位(wei)基(ji)(ji)準(zhun)有精(jing)基(ji)(ji)準(zhun)與粗(cu)基(ji)(ji)準(zhun)之分。用(yong)毛(mao)坯上未經加工(gong)的表(biao)(biao)面作(zuo)定(ding)位(wei)基(ji)(ji)準(zhun)，這種(zhong)定(ding)位(wei)基(ji)(ji)準(zhun)稱為粗(cu)基(ji)(ji)準(zhun)；用(yong)加工(gong)過的表(biao)(biao)面作(zuo)定(ding)位(wei)基(ji)(ji)準(zhun)，這種(zhong)定(ding)位(wei)基(ji)(ji)準(zhun)稱為精(jing)基(ji)(ji)準(zhun)。在(zai)選(xuan)擇(ze)定(ding)位(wei)基(ji)(ji)準(zhun)時一般都是先根據零(ling)件(jian)(jian)的加工(gong)要(yao)求選(xuan)擇(ze)精(jing)基(ji)(ji)準(zhun)，然(ran)后再考慮用(yong)那(nei)一組表(biao)(biao)面作(zuo)粗(cu)基(ji)(ji)準(zhun)才能(neng)把精(jing)基(ji)(ji)準(zhun)加工(gong)出來。
1．精基(ji)準的選擇原則
選擇(ze)精基準一(yi)般應遵循以下幾項原則：
（1）基(ji)準重合原則
（2）統一(yi)基(ji)準原(yuan)則(ze)
（3）互為(wei)基準原則
（4）自為(wei)基準原則(ze)
2．粗基準(zhun)的選擇原則
工(gong)(gong)件加工(gong)(gong)的(de)(de)第一(yi)道工(gong)(gong)序(xu)所用基(ji)(ji)準都是粗(cu)基(ji)(ji)準，粗(cu)基(ji)(ji)準選(xuan)擇得(de)正確與否，不但與第一(yi)道工(gong)(gong)序(xu)的(de)(de)加工(gong)(gong)有關，而且(qie)還將對(dui)該工(gong)(gong)件加工(gong)(gong)的(de)(de)全過程產生(sheng)重大(da)影響。選(xuan)擇粗(cu)基(ji)(ji)準，一(yi)般應遵(zun)循以下幾項原則：
（1）保證零件(jian)加(jia)工表(biao)面(mian)(mian)相對于不加(jia)工表(biao)面(mian)(mian)具有一定(ding)位(wei)置精度的原則
（2）合理分配加(jia)工(gong)余量的(de)原則
（3）便于裝夾的原則
（4）在同一尺寸方向上粗基準(zhun)一般不得重復使用的原則
（二）零件表(biao)面(mian)加(jia)工方法的選(xuan)擇
（三）加工階段的劃分(fen)
當零(ling)件的(de)加(jia)工(gong)(gong)質量要(yao)(yao)(yao)求(qiu)較高(gao)時(shi)，一般都要(yao)(yao)(yao)經(jing)過粗(cu)加(jia)工(gong)(gong)、半精加(jia)工(gong)(gong)和(he)精加(jia)工(gong)(gong)等三個階段(duan)；如(ru)果零(ling)件的(de)加(jia)工(gong)(gong)精度要(yao)(yao)(yao)求(qiu)特別(bie)高(gao)、表(biao)面粗(cu)糙度要(yao)(yao)(yao)求(qiu)特別(bie)小時(shi)，還要(yao)(yao)(yao)經(jing)過光整加(jia)工(gong)(gong)階段(duan)。各個加(jia)工(gong)(gong)階段(duan)的(de)主(zhu)要(yao)(yao)(yao)任(ren)務是：
（1）粗加工階段(duan)
（2）半精(jing)加工階段(duan)
（3）精加工(gong)階段
（4）光(guang)整加(jia)工階段
將零件(jian)的(de)加(jia)工過程劃(hua)分為(wei)幾個(ge)加(jia)工階段的(de)主要目的(de)是：
（1）保(bao)證零件加(jia)工質量
（2）有利于及早發(fa)現毛坯缺陷并(bing)得到及時處理
（3）有利于合理利用機床(chuang)設(she)備(bei)
在(zai)選(xuan)擇(ze)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)方(fang)法(fa)(fa)時，一(yi)般總是首(shou)先(xian)根據零(ling)件(jian)主(zhu)要(yao)表(biao)面(mian)的(de)(de)(de)技術要(yao)求和工(gong)(gong)(gong)(gong)廠具(ju)體條件(jian)，先(xian)選(xuan)定(ding)該表(biao)面(mian)終加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)序(xu)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)方(fang)法(fa)(fa)，然后再(zai)逐一(yi)選(xuan)定(ding)該表(biao)面(mian)各有關(guan)前(qian)導(dao)(dao)工(gong)(gong)(gong)(gong)序(xu)的(de)(de)(de)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)方(fang)法(fa)(fa)。例如，加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)一(yi)個精度(du)等級為(wei)(wei)1T6、表(biao)面(mian)粗糙(cao)度(du)為(wei)(wei)0.2的(de)(de)(de)鋼件(jian)外圓(yuan)表(biao)面(mian)，其(qi)終加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)序(xu)選(xuan)用精磨，則(ze)其(qi)前(qian)導(dao)(dao)工(gong)(gong)(gong)(gong)序(xu)可分別(bie)選(xuan)為(wei)(wei)粗車(che)、半精車(che)和粗磨（參見圖5-5）。主(zhu)要(yao)表(biao)面(mian)的(de)(de)(de)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)方(fang)案和加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)方(fang)法(fa)(fa)選(xuan)定(ding)之后，再(zai)選(xuan)定(ding)次要(yao)表(biao)面(mian)的(de)(de)(de)加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)方(fang)案和加(jia)(jia)(jia)工(gong)(gong)(gong)(gong)方(fang)法(fa)(fa)。
（三(san)）加(jia)工階段的劃分
當(dang)零(ling)件的加工(gong)質量要(yao)求較高時(shi)，一般都要(yao)經過(guo)粗加工(gong)、半精(jing)加工(gong)和精(jing)加工(gong)等三個階段；如果零(ling)件的加工(gong)精(jing)度(du)要(yao)求特別(bie)高、表面(mian)粗糙度(du)要(yao)求特別(bie)小時(shi)，還要(yao)經過(guo)光整加工(gong)階段。各個加工(gong)階段的主要(yao)任務是：
（1）粗加(jia)工階段(duan)高效地(di)切(qie)除加(jia)工表面上(shang)的大部(bu)分余(yu)量，使(shi)毛坯在形狀和尺寸上(shang)接近成(cheng)品零件。
（2）半精加工階段去除粗加工后留下的誤差和缺陷，使被加工工件達到一定精度，為精加工作準備，并完成一些次要表面的加工，例如鉆孔、攻絲、銑鍵槽等。
（3）精加工(gong)階段保證各主(zhu)要表面達到零件圖規定的加工(gong)質量(liang)要求。
（4）光整加工(gong)階段對于精度要求(qiu)很高（IT5以上(shang)）、表(biao)面(mian)(mian)粗(cu)糙度值(zhi)要求(qiu)很小(xiao)（0.2μm）的(de)表(biao)面(mian)(mian)，尚需設置(zhi)(zhi)光整加工(gong)階段，其主要任務是(shi)降低表(biao)面(mian)(mian)粗(cu)糙度和(he)進一(yi)步提高尺(chi)寸精度和(he)形狀精度，但一(yi)般沒有提高表(biao)面(mian)(mian)間位置(zhi)(zhi)精度的(de)作(zuo)用。
將(jiang)零件的加工(gong)(gong)過程劃分(fen)為幾個加工(gong)(gong)階段的主要目的是(shi)：
（1）保證零件(jian)加(jia)工(gong)(gong)(gong)(gong)質量(liang)粗(cu)(cu)加(jia)工(gong)(gong)(gong)(gong)階(jie)(jie)段(duan)(duan)要(yao)切(qie)除加(jia)工(gong)(gong)(gong)(gong)表面上的(de)大(da)部(bu)分余量(liang)，切(qie)削(xue)力(li)和切(qie)削(xue)熱(re)都比(bi)較大(da)，裝夾工(gong)(gong)(gong)(gong)件(jian)所需夾緊力(li)亦(yi)較大(da)，被(bei)加(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)件(jian)會產(chan)生(sheng)較大(da)的(de)受力(li)變形(xing)和受熱(re)變形(xing)；此(ci)外，粗(cu)(cu)加(jia)工(gong)(gong)(gong)(gong)階(jie)(jie)段(duan)(duan)從工(gong)(gong)(gong)(gong)件(jian)上切(qie)除大(da)部(bu)分余量(liang)后，殘存在(zai)工(gong)(gong)(gong)(gong)件(jian)中的(de)內應力(li)要(yao)重(zhong)新分布(bu)，也會使工(gong)(gong)(gong)(gong)件(jian)產(chan)生(sheng)變形(xing)。如果(guo)加(jia)工(gong)(gong)(gong)(gong)過(guo)(guo)程(cheng)(cheng)不劃分階(jie)(jie)段(duan)(duan)，把各個表面的(de)粗(cu)(cu)、精(jing)(jing)加(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)序混在(zai)一起交錯進行，那么(me)安(an)排(pai)在(zai)工(gong)(gong)(gong)(gong)藝過(guo)(guo)程(cheng)(cheng)前期通過(guo)(guo)精(jing)(jing)加(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)序獲(huo)得的(de)加(jia)工(gong)(gong)(gong)(gong)精(jing)(jing)度勢必會被(bei)后續的(de)粗(cu)(cu)加(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)序所破壞(huai)，這是不合(he)理的(de)。加(jia)工(gong)(gong)(gong)(gong)過(guo)(guo)程(cheng)(cheng)劃分為幾個階(jie)(jie)段(duan)(duan)以后，粗(cu)(cu)加(jia)工(gong)(gong)(gong)(gong)階(jie)(jie)段(duan)(duan)產(chan)生(sheng)的(de)誤差和缺陷(xian)，可以通過(guo)(guo)半精(jing)(jing)加(jia)工(gong)(gong)(gong)(gong)和精(jing)(jing)加(jia)工(gong)(gong)(gong)(gong)階(jie)(jie)段(duan)(duan)逐步予(yu)以修正，零件(jian)的(de)加(jia)工(gong)(gong)(gong)(gong)質量(liang)可以得到保證。
（2）有利于及早發現毛坯缺陷并得到及時處理粗加工各表面后，由于切除了各加工表面的大部分加工余量，可及早發現毛坯的缺陷（氣孔、砂眼、裂紋和加工余量不夠），以便及時報廢或修補，不(bu)會浪費后續(xu)精加工(gong)工(gong)序的制造費用。
（3）有利于合理利用機(ji)床(chuang)(chuang)設備粗(cu)加(jia)(jia)工(gong)(gong)(gong)工(gong)(gong)(gong)序需選用功率(lv)大(da)、精(jing)度(du)(du)不高(gao)(gao)的機(ji)床(chuang)(chuang)加(jia)(jia)工(gong)(gong)(gong)，精(jing)加(jia)(jia)工(gong)(gong)(gong)工(gong)(gong)(gong)序則(ze)應選用高(gao)(gao)精(jing)度(du)(du)機(ji)床(chuang)(chuang)加(jia)(jia)工(gong)(gong)(gong)。在高(gao)(gao)精(jing)度(du)(du)機(ji)床(chuang)(chuang)上(shang)安排做(zuo)粗(cu)加(jia)(jia)工(gong)(gong)(gong)工(gong)(gong)(gong)作(zuo)，機(ji)床(chuang)(chuang)精(jing)度(du)(du)會迅速下降，將某一表(biao)面(mian)的粗(cu)、精(jing)加(jia)(jia)工(gong)(gong)(gong)工(gong)(gong)(gong)作(zuo)安排在同一機(ji)床(chuang)(chuang)上(shang)加(jia)(jia)工(gong)(gong)(gong)是不合理的。
應當指(zhi)出，將(jiang)工(gong)(gong)藝過程劃分成幾(ji)個不同的(de)加(jia)工(gong)(gong)階段(duan)(duan)進行是對零件(jian)整個加(jia)工(gong)(gong)過程而(er)言(yan)的(de)，不能拘泥于某一表(biao)面(mian)的(de)加(jia)工(gong)(gong)，例如，工(gong)(gong)件(jian)的(de)定位基面(mian)，在半(ban)精(jing)加(jia)工(gong)(gong)階段(duan)(duan)（有時甚至在粗加(jia)工(gong)(gong)階段(duan)(duan)）中就需要(yao)加(jia)工(gong)(gong)得很精(jing)確；而(er)在精(jing)加(jia)工(gong)(gong)階段(duan)(duan)中安排某些鉆、攻螺紋孔之類的(de)粗加(jia)工(gong)(gong)工(gong)(gong)序也(ye)是常見(jian)的(de)。
當然(ran)，劃(hua)(hua)分(fen)加(jia)(jia)(jia)工(gong)(gong)(gong)階(jie)(jie)段并不(bu)是絕對(dui)的。在(zai)高剛度(du)、高精(jing)(jing)(jing)度(du)機床設(she)備上加(jia)(jia)(jia)工(gong)(gong)(gong)剛性(xing)好、加(jia)(jia)(jia)工(gong)(gong)(gong)精(jing)(jing)(jing)度(du)要(yao)求不(bu)特(te)別高或加(jia)(jia)(jia)工(gong)(gong)(gong)余量不(bu)太大的工(gong)(gong)(gong)件(jian)(jian)就可以不(bu)必劃(hua)(hua)分(fen)加(jia)(jia)(jia)工(gong)(gong)(gong)階(jie)(jie)段；有些精(jing)(jing)(jing)度(du)要(yao)求不(bu)太高的重型零件(jian)(jian)，由于運送工(gong)(gong)(gong)件(jian)(jian)和裝夾工(gong)(gong)(gong)件(jian)(jian)費時費工(gong)(gong)(gong)，一(yi)般也(ye)不(bu)劃(hua)(hua)分(fen)加(jia)(jia)(jia)工(gong)(gong)(gong)階(jie)(jie)段，而(er)是在(zai)一(yi)個工(gong)(gong)(gong)序中完成全部粗(cu)加(jia)(jia)(jia)工(gong)(gong)(gong)和精(jing)(jing)(jing)加(jia)(jia)(jia)工(gong)(gong)(gong)工(gong)(gong)(gong)作；在(zai)這類加(jia)(jia)(jia)工(gong)(gong)(gong)中，為減(jian)少夾緊變形對(dui)工(gong)(gong)(gong)件(jian)(jian)加(jia)(jia)(jia)工(gong)(gong)(gong)精(jing)(jing)(jing)度(du)的影(ying)響，一(yi)般都(dou)在(zai)粗(cu)加(jia)(jia)(jia)工(gong)(gong)(gong)后松(song)開夾緊裝置，然(ran)后用較小的夾緊力(li)重新夾緊工(gong)(gong)(gong)件(jian)(jian)，繼續(xu)進行精(jing)(jing)(jing)加(jia)(jia)(jia)工(gong)(gong)(gong)，這對(dui)提高工(gong)(gong)(gong)件(jian)(jian)加(jia)(jia)(jia)工(gong)(gong)(gong)精(jing)(jing)(jing)度(du)有利。
（四）工序的集中與分散
確(que)定(ding)加(jia)工(gong)(gong)(gong)(gong)方法之后，就(jiu)要按零件(jian)加(jia)工(gong)(gong)(gong)(gong)的(de)(de)(de)生(sheng)(sheng)產類型(xing)和(he)工(gong)(gong)(gong)(gong)廠（車間）生(sheng)(sheng)產條(tiao)件(jian)確(que)定(ding)工(gong)(gong)(gong)(gong)藝過(guo)程(cheng)的(de)(de)(de)工(gong)(gong)(gong)(gong)序數。確(que)定(ding)零件(jian)加(jia)工(gong)(gong)(gong)(gong)過(guo)程(cheng)工(gong)(gong)(gong)(gong)序數有兩種迥然不同的(de)(de)(de)原(yuan)則，一(yi)種是(shi)工(gong)(gong)(gong)(gong)序集(ji)中(zhong)原(yuan)則，另一(yi)種是(shi)工(gong)(gong)(gong)(gong)序分(fen)散(san)原(yuan)則。按工(gong)(gong)(gong)(gong)序集(ji)中(zhong)原(yuan)則組織(zhi)工(gong)(gong)(gong)(gong)藝過(guo)程(cheng)，就(jiu)是(shi)使每個(ge)工(gong)(gong)(gong)(gong)序所(suo)包括(kuo)的(de)(de)(de)加(jia)工(gong)(gong)(gong)(gong)內(nei)容盡量多些，組成(cheng)一(yi)個(ge)集(ji)中(zhong)工(gong)(gong)(gong)(gong)序；最(zui)大(da)限度的(de)(de)(de)工(gong)(gong)(gong)(gong)序集(ji)中(zhong)，就(jiu)是(shi)在一(yi)個(ge)工(gong)(gong)(gong)(gong)序內(nei)完成(cheng)工(gong)(gong)(gong)(gong)件(jian)所(suo)有表面的(de)(de)(de)加(jia)工(gong)(gong)(gong)(gong)。按工(gong)(gong)(gong)(gong)序分(fen)散(san)原(yuan)則組織(zhi)工(gong)(gong)(gong)(gong)藝過(guo)程(cheng)，就(jiu)是(shi)使每個(ge)工(gong)(gong)(gong)(gong)序所(suo)包括(kuo)的(de)(de)(de)加(jia)工(gong)(gong)(gong)(gong)內(nei)容盡量少些；最(zui)大(da)限度的(de)(de)(de)工(gong)(gong)(gong)(gong)序分(fen)散(san)就(jiu)是(shi)使每個(ge)工(gong)(gong)(gong)(gong)序只包括(kuo)一(yi)個(ge)簡(jian)單(dan)工(gong)(gong)(gong)(gong)步。
按工序集(ji)中原(yuan)則組織工藝(yi)過程的特點是：
1）有(you)利于采用自動化程度較高(gao)(gao)的高(gao)(gao)效(xiao)(xiao)率機床和工藝裝(zhuang)備進行加(jia)工，生產效(xiao)(xiao)率高(gao)(gao)；
2）工序數少，設備數少，可(ke)相應減少操作(zuo)工人數和(he)生產面積；
3）工(gong)(gong)件的裝夾次(ci)數(shu)少(shao)，不但可縮短輔助時間(jian)，而(er)且由于在一次(ci)裝夾中加工(gong)(gong)了許多(duo)表面，有利于保(bao)證(zheng)各加工(gong)(gong)表面之間(jian)的相(xiang)互位(wei)置精度要求(qiu)。
按(an)工序分散原(yuan)則(ze)組(zu)織工藝過程(cheng)的特點是：
1）所(suo)用(yong)機床和工藝裝備簡單，易于調整；
2）對操作工人的技術水平要求(qiu)不高；
3）工序(xu)數多，設備數多，操作工人多，占用生產面積大。
按工(gong)序集中原(yuan)(yuan)則(ze)和工(gong)序分散(san)原(yuan)(yuan)則(ze)組(zu)(zu)織(zhi)工(gong)藝過程(cheng)各有特點，生(sheng)(sheng)產(chan)(chan)(chan)上(shang)都有應(ying)(ying)用。傳統的以專用機(ji)床、組(zu)(zu)合機(ji)床為主體組(zu)(zu)建的流(liu)水生(sheng)(sheng)產(chan)(chan)(chan)線、自動生(sheng)(sheng)產(chan)(chan)(chan)線基本(ben)是按工(gong)序分散(san)原(yuan)(yuan)則(ze)組(zu)(zu)織(zhi)工(gong)藝過程(cheng)的，可以實現高效生(sheng)(sheng)產(chan)(chan)(chan)，但對(dui)產(chan)(chan)(chan)品改型的適(shi)應(ying)(ying)性較(jiao)(jiao)差(cha)，轉產(chan)(chan)(chan)比較(jiao)(jiao)困難。采用數控機(ji)床和加工(gong)中心加工(gong)零件都按工(gong)序集中原(yuan)(yuan)則(ze)組(zu)(zu)織(zhi)工(gong)藝過程(cheng)，雖然(ran)設備的一次性投資較(jiao)(jiao)高，但由于可重組(zu)(zu)生(sheng)(sheng)產(chan)(chan)(chan)的能力較(jiao)(jiao)強，生(sheng)(sheng)產(chan)(chan)(chan)適(shi)應(ying)(ying)性好，轉產(chan)(chan)(chan)相(xiang)對(dui)容易，仍然(ran)受到愈來愈多的重視。
（五）工序先后順序的安排
1．機械(xie)加工工序(xu)的安排
機械加工工序(xu)(xu)先后順序(xu)(xu)的(de)安排，一般應遵循以下幾個原(yuan)則(ze)：
1）先加工定(ding)位基(ji)面，再(zai)加工其(qi)它表面；
2）先加(jia)工主(zhu)要表面，后(hou)加(jia)工次要表面；
3）先安排(pai)粗(cu)加工(gong)(gong)(gong)工(gong)(gong)(gong)序，后安排(pai)精加工(gong)(gong)(gong)工(gong)(gong)(gong)序；
4）先加工平面，后(hou)加工孔。
安排數(shu)控(kong)加(jia)工(gong)(gong)(gong)(gong)順(shun)(shun)序，尚(shang)須(xu)考慮以(yi)下(xia)情況：（1）在換刀(dao)(dao)時間(jian)大于(yu)工(gong)(gong)(gong)(gong)作(zuo)臺(tai)(tai)轉位(wei)(wei)時間(jian)的(de)(de)情況下(xia)，為減(jian)少(shao)換刀(dao)(dao)次(ci)數(shu)和(he)換刀(dao)(dao)時間(jian)，在不(bu)影響加(jia)工(gong)(gong)(gong)(gong)精度(du)的(de)(de)條件下(xia)，宜將所(suo)有(you)能(neng)用同一(yi)把刀(dao)(dao)具加(jia)工(gong)(gong)(gong)(gong)的(de)(de)表面都集(ji)中在一(yi)起依次(ci)完成；（2）為減(jian)少(shao)工(gong)(gong)(gong)(gong)作(zuo)臺(tai)(tai)轉位(wei)(wei)誤差和(he)由于(yu)工(gong)(gong)(gong)(gong)作(zuo)臺(tai)(tai)轉位(wei)(wei)帶來的(de)(de)時間(jian)損失(shi)，在換刀(dao)(dao)時間(jian)小于(yu)工(gong)(gong)(gong)(gong)作(zuo)臺(tai)(tai)轉位(wei)(wei)時間(jian)的(de)(de)情況下(xia)，采用工(gong)(gong)(gong)(gong)位(wei)(wei)集(ji)中加(jia)工(gong)(gong)(gong)(gong)原(yuan)則安排加(jia)工(gong)(gong)(gong)(gong)順(shun)(shun)序，即將所(suo)有(you)能(neng)在一(yi)個工(gong)(gong)(gong)(gong)位(wei)(wei)加(jia)工(gong)(gong)(gong)(gong)的(de)(de)表面通過(guo)不(bu)斷更換刀(dao)(dao)具的(de)(de)辦法都集(ji)中在同一(yi)工(gong)(gong)(gong)(gong)位(wei)(wei)加(jia)工(gong)(gong)(gong)(gong)；（3）對于(yu)位(wei)(wei)置精度(du)要(yao)求(qiu)很高的(de)(de)孔系(xi)(xi)，宜在同一(yi)工(gong)(gong)(gong)(gong)位(wei)(wei)中安排該孔系(xi)(xi)各相關表面的(de)(de)加(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)作(zuo)，以(yi)消除工(gong)(gong)(gong)(gong)作(zuo)臺(tai)(tai)轉位(wei)(wei)重復定位(wei)(wei)誤差對孔系(xi)(xi)位(wei)(wei)置精度(du)要(yao)求(qiu)的(de)(de)影響。
2．熱處理工序及表面(mian)處理工序的安排
為(wei)改善工(gong)件材料切削(xue)性能(neng)安排(pai)的熱處(chu)理工(gong)序，例(li)如(ru)退火(huo)(huo)、正(zheng)火(huo)(huo)、調質等，應在切削(xue)加(jia)工(gong)之前進行。
所謂(wei)人工時效，就(jiu)是將毛坯件(jian)以50~100℃/h的(de)(de)速(su)度加熱到500~550℃，保溫3~5h，然后以20~50℃/h的(de)(de)速(su)度隨爐冷卻。所謂(wei)自然時效就(jiu)是將毛坯件(jian)在露(lu)天放置幾(ji)(ji)個月到幾(ji)(ji)年時間，讓毛坯件(jian)在自然界經受日(ri)曬雨(yu)淋的(de)(de)“錘煉”，使材(cai)料組織內部松弛并逐(zhu)漸趨(qu)于(yu)穩定。
3．其(qi)它工序的安排
為(wei)保(bao)證零件制造質量，防(fang)止產生廢(fei)品(pin)，需(xu)在下(xia)列(lie)場合安(an)排檢驗(yan)工序(xu)：1）粗加(jia)工全(quan)部(bu)結束之后(hou)；2）送往外(wai)車間加(jia)工的前后(hou)；3）工時(shi)較長工序(xu)和重要工序(xu)的前后(hou)；4）最終(zhong)加(jia)工之后(hou)，除了安(an)排幾何尺寸檢驗(yan)工序(xu)之外(wai)，有的零件還要安(an)排探傷、密封、稱重、平衡(heng)等檢驗(yan)工序(xu)。
零件表層或內(nei)腔的(de)毛刺(ci)對機器裝配質量影(ying)響甚大，切削加工之后，應(ying)安排去(qu)毛刺(ci)工序。
零件(jian)(jian)在進入裝配之前，一般都(dou)應安(an)排清(qing)洗工(gong)(gong)(gong)序。工(gong)(gong)(gong)件(jian)(jian)內孔、箱體(ti)內腔易存留切(qie)屑，研磨、珩磨等光整加工(gong)(gong)(gong)工(gong)(gong)(gong)序之后，微小磨粒易附著在工(gong)(gong)(gong)件(jian)(jian)表(biao)面上，要注意清(qing)洗。
在用磁(ci)力夾緊的工序(xu)之(zhi)后，要安排去磁(ci)工序(xu)，不(bu)讓帶有(you)剩磁(ci)的工件進入裝配線。
（六）機床設備(bei)與工(gong)藝裝備(bei)的選擇
（七）實例
（一）概述
用去除(chu)材(cai)料方(fang)法制造機器零件(jian)時(shi)，一般都要從毛坯(pi)上切除(chu)一層層材(cai)料之(zhi)后最后才能制得符合圖紙規(gui)定要求的(de)(de)(de)零件(jian)。毛坯(pi)上留作(zuo)加工(gong)用的(de)(de)(de)材(cai)料層，稱為加工(gong)余量。加工(gong)余量有總(zong)(zong)余量和工(gong)序(xu)余量之(zhi)分。某一表面毛坯(pi)尺(chi)寸與零件(jian)設計尺(chi)寸的(de)(de)(de)差值就是(shi)總(zong)(zong)余量值，以Z0表示。上工(gong)序(xu)與本(ben)工(gong)序(xu)基本(ben)尺(chi)寸的(de)(de)(de)差值為本(ben)工(gong)序(xu)的(de)(de)(de)工(gong)序(xu)余量Zi。
工(gong)序余量(liang)有單邊余量(liang)和雙(shuang)邊余量(liang)之分。
由于工序(xu)尺(chi)寸(cun)有偏差(cha)，各(ge)工序(xu)實(shi)際切除(chu)的余(yu)量值是變化的，工序(xu)余(yu)量有公稱余(yu)量（簡稱余(yu)量）、最大余(yu)量和最小余(yu)量之分。
工序尺(chi)(chi)寸(cun)偏(pian)(pian)(pian)差(cha)(cha)一般按(an)(an)“入體原則”標注，對被包容(rong)尺(chi)(chi)寸(cun)（例如軸徑），上偏(pian)(pian)(pian)差(cha)(cha)為(wei)0，其最(zui)大尺(chi)(chi)寸(cun)就是基本(ben)尺(chi)(chi)寸(cun)；對包容(rong)尺(chi)(chi)寸(cun)（例如孔徑、槽寬），下偏(pian)(pian)(pian)差(cha)(cha)為(wei)0，其最(zui)小(xiao)尺(chi)(chi)寸(cun)就是基本(ben)尺(chi)(chi)寸(cun)；孔距(ju)類工序尺(chi)(chi)寸(cun)偏(pian)(pian)(pian)差(cha)(cha)按(an)(an)“對稱(cheng)偏(pian)(pian)(pian)差(cha)(cha)”配置。
（二）影響加工余量的(de)因(yin)素(su)
為(wei)了(le)合理確定加工余(yu)量，必須(xu)深(shen)入了(le)解(jie)影響(xiang)(xiang)加工余(yu)量的各項因素(su)(su)。影響(xiang)(xiang)加工余(yu)量的因素(su)(su)有以下四個方(fang)面：
（1）上(shang)工序(xu)留(liu)下的表(biao)(biao)面粗糙度值Rz（表(biao)(biao)面輪廓的最大(da)高(gao)度）和表(biao)(biao)面缺陷層深度Ha
（2）上工(gong)序的尺寸公差Ta
（3）Ta值沒有包(bao)括的(de)上工序留下的(de)空間位(wei)置誤(wu)差(cha)ea
（4）本工序的裝夾(jia)誤差εb
（三）加工(gong)余(yu)量的確(que)定
確定加工(gong)余量有計(ji)算法(fa)(fa)、查(cha)表法(fa)(fa)和經(jing)(jing)驗估計(ji)法(fa)(fa)等(deng)三(san)種(zhong)方法(fa)(fa)：計(ji)算法(fa)(fa)；經(jing)(jing)驗估計(ji)法(fa)(fa)；查(cha)表法(fa)(fa)。
零(ling)(ling)件圖上所標注的(de)(de)(de)尺(chi)(chi)(chi)(chi)寸(cun)(cun)公差是零(ling)(ling)件加(jia)工(gong)(gong)(gong)最(zui)終所要求達到的(de)(de)(de)尺(chi)(chi)(chi)(chi)寸(cun)(cun)要求，工(gong)(gong)(gong)藝過(guo)程中(zhong)許多中(zhong)間工(gong)(gong)(gong)序(xu)的(de)(de)(de)尺(chi)(chi)(chi)(chi)寸(cun)(cun)公差，必(bi)須(xu)在設(she)計(ji)(ji)工(gong)(gong)(gong)藝規程中(zhong)予以(yi)確(que)(que)定(ding)。工(gong)(gong)(gong)序(xu)尺(chi)(chi)(chi)(chi)寸(cun)(cun)及其(qi)(qi)公差一(yi)般都是通過(guo)解算工(gong)(gong)(gong)藝尺(chi)(chi)(chi)(chi)寸(cun)(cun)鏈(lian)確(que)(que)定(ding)的(de)(de)(de)。為(wei)掌握工(gong)(gong)(gong)藝尺(chi)(chi)(chi)(chi)寸(cun)(cun)鏈(lian)計(ji)(ji)算規律，這里先介紹(shao)尺(chi)(chi)(chi)(chi)寸(cun)(cun)鏈(lian)的(de)(de)(de)概念及尺(chi)(chi)(chi)(chi)寸(cun)(cun)鏈(lian)計(ji)(ji)算方法(fa)，然后再(zai)就工(gong)(gong)(gong)序(xu)尺(chi)(chi)(chi)(chi)寸(cun)(cun)及其(qi)(qi)公差的(de)(de)(de)確(que)(que)定(ding)方法(fa)進行(xing)論述。
（一）尺(chi)寸鏈及尺(chi)寸鏈計算(suan)公式
1．尺寸鏈的定(ding)義
在工(gong)件(jian)加(jia)工(gong)和機器裝配過(guo)程(cheng)中(zhong)，由相互連接(jie)(jie)的(de)(de)(de)尺(chi)(chi)寸(cun)(cun)(cun)形成(cheng)(cheng)(cheng)的(de)(de)(de)封(feng)(feng)(feng)閉(bi)尺(chi)(chi)寸(cun)(cun)(cun)組(zu)(zu)，稱(cheng)(cheng)(cheng)(cheng)為尺(chi)(chi)寸(cun)(cun)(cun)鏈(lian)(lian)。組(zu)(zu)成(cheng)(cheng)(cheng)尺(chi)(chi)寸(cun)(cun)(cun)鏈(lian)(lian)的(de)(de)(de)每一個尺(chi)(chi)寸(cun)(cun)(cun)，稱(cheng)(cheng)(cheng)(cheng)為尺(chi)(chi)寸(cun)(cun)(cun)鏈(lian)(lian)的(de)(de)(de)環(huan)(huan)。尺(chi)(chi)寸(cun)(cun)(cun)鏈(lian)(lian)中(zhong)凡屬間(jian)接(jie)(jie)得到的(de)(de)(de)尺(chi)(chi)寸(cun)(cun)(cun)稱(cheng)(cheng)(cheng)(cheng)為封(feng)(feng)(feng)閉(bi)環(huan)(huan)，尺(chi)(chi)寸(cun)(cun)(cun)鏈(lian)(lian)中(zhong)凡屬通過(guo)加(jia)工(gong)直接(jie)(jie)得到的(de)(de)(de)尺(chi)(chi)寸(cun)(cun)(cun)稱(cheng)(cheng)(cheng)(cheng)為組(zu)(zu)成(cheng)(cheng)(cheng)環(huan)(huan)；組(zu)(zu)成(cheng)(cheng)(cheng)環(huan)(huan)按其對封(feng)(feng)(feng)閉(bi)環(huan)(huan)的(de)(de)(de)影(ying)響(xiang)又可分(fen)為增(zeng)(zeng)環(huan)(huan)和減(jian)環(huan)(huan)。當(dang)其它(ta)組(zu)(zu)成(cheng)(cheng)(cheng)環(huan)(huan)的(de)(de)(de)大小(xiao)不變，若封(feng)(feng)(feng)閉(bi)環(huan)(huan)隨著(zhu)(zhu)某組(zu)(zu)成(cheng)(cheng)(cheng)環(huan)(huan)的(de)(de)(de)增(zeng)(zeng)大而(er)增(zeng)(zeng)大，則(ze)此(ci)組(zu)(zu)成(cheng)(cheng)(cheng)環(huan)(huan)就稱(cheng)(cheng)(cheng)(cheng)為增(zeng)(zeng)環(huan)(huan)；若封(feng)(feng)(feng)閉(bi)環(huan)(huan)隨著(zhu)(zhu)某組(zu)(zu)成(cheng)(cheng)(cheng)環(huan)(huan)的(de)(de)(de)增(zeng)(zeng)大而(er)減(jian)小(xiao)，則(ze)此(ci)組(zu)(zu)成(cheng)(cheng)(cheng)環(huan)(huan)就稱(cheng)(cheng)(cheng)(cheng)為減(jian)環(huan)(huan)。
2．尺寸鏈的分類
按(an)尺(chi)(chi)寸(cun)鏈(lian)在空間分布的位置關系，可分為直線尺(chi)(chi)寸(cun)鏈(lian)、平面(mian)尺(chi)(chi)寸(cun)鏈(lian)和空間尺(chi)(chi)寸(cun)鏈(lian)。
3．尺寸鏈計算
尺(chi)寸(cun)鏈計算(suan)(suan)有正計算(suan)(suan)、反(fan)計算(suan)(suan)和(he)中間計算(suan)(suan)等(deng)三(san)種類型。已(yi)知組成(cheng)環(huan)(huan)(huan)尺(chi)寸(cun)、公差(cha)求封(feng)閉環(huan)(huan)(huan)尺(chi)寸(cun)、公差(cha)的計算(suan)(suan)方(fang)式(shi)稱(cheng)作正計算(suan)(suan)；已(yi)知封(feng)閉環(huan)(huan)(huan)尺(chi)寸(cun)、公差(cha)反(fan)求各(ge)組成(cheng)環(huan)(huan)(huan)尺(chi)寸(cun)、公差(cha)稱(cheng)作反(fan)計算(suan)(suan)；已(yi)知封(feng)閉環(huan)(huan)(huan)及部分組成(cheng)環(huan)(huan)(huan)的尺(chi)寸(cun)、公差(cha)，求其余的一個或幾個組成(cheng)環(huan)(huan)(huan)尺(chi)寸(cun)、公差(cha)，稱(cheng)作中間計算(suan)(suan)。
尺(chi)(chi)(chi)寸鏈計(ji)算有極(ji)值法與統計(ji)法兩種。用極(ji)值法解尺(chi)(chi)(chi)寸鏈是(shi)按尺(chi)(chi)(chi)寸鏈各環均處于極(ji)值條件(jian)來分析計(ji)算封閉環尺(chi)(chi)(chi)寸與組成環尺(chi)(chi)(chi)寸之間(jian)關(guan)(guan)系(xi)的。用統計(ji)法解尺(chi)(chi)(chi)寸鏈則是(shi)運用概率論理論來分析計(ji)算封閉環尺(chi)(chi)(chi)寸與組成環尺(chi)(chi)(chi)寸之間(jian)關(guan)(guan)系(xi)的。
4．用極值(zhi)法解(jie)算(suan)直線尺寸鏈基本計(ji)算(suan)公式
5．用統(tong)計法解算直線尺寸鏈基本計算公式
（二）工藝尺寸及其公差的計算(suan)實例
1．定(ding)位基準與設計基準不重合時工序尺寸公(gong)差(cha)的計算
2．一次加(jia)工(gong)滿(man)足多個設計尺(chi)寸(cun)要求(qiu)時工(gong)序尺(chi)寸(cun)及其公差的(de)計算
3．用綜(zong)合圖(tu)表跟蹤法計算工(gong)序尺寸及其公差
（一）時間定(ding)(ding)額(e)所(suo)謂(wei)時間定(ding)(ding)額(e)是指在一定(ding)(ding)生(sheng)(sheng)產(chan)(chan)(chan)(chan)(chan)條(tiao)件(jian)下規定(ding)(ding)生(sheng)(sheng)產(chan)(chan)(chan)(chan)(chan)一件(jian)產(chan)(chan)(chan)(chan)(chan)品或完成(cheng)一道工(gong)序所(suo)需(xu)消(xiao)耗(hao)的(de)(de)(de)時間。時間定(ding)(ding)額(e)是安排作業計(ji)劃(hua)、進(jin)(jin)行成(cheng)本(ben)核算(suan)的(de)(de)(de)重(zhong)要依(yi)據，也是設(she)計(ji)或擴建工(gong)廠（或車間）時計(ji)算(suan)設(she)備和(he)工(gong)人數量(liang)的(de)(de)(de)依(yi)據。時間定(ding)(ding)額(e)規定(ding)(ding)得(de)過(guo)緊會(hui)影(ying)響生(sheng)(sheng)產(chan)(chan)(chan)(chan)(chan)工(gong)人的(de)(de)(de)勞動積極(ji)性和(he)創造性，并(bing)容易誘發忽視產(chan)(chan)(chan)(chan)(chan)品質量(liang)的(de)(de)(de)傾向；時間定(ding)(ding)額(e)規定(ding)(ding)得(de)過(guo)松就起(qi)不到指導生(sheng)(sheng)產(chan)(chan)(chan)(chan)(chan)和(he)促進(jin)(jin)生(sheng)(sheng)產(chan)(chan)(chan)(chan)(chan)發展的(de)(de)(de)積極(ji)作用。合理制訂時間定(ding)(ding)額(e)對保證產(chan)(chan)(chan)(chan)(chan)品加工(gong)質量(liang)、提高(gao)勞動生(sheng)(sheng)產(chan)(chan)(chan)(chan)(chan)率、降低(di)生(sheng)(sheng)產(chan)(chan)(chan)(chan)(chan)成(cheng)本(ben)具有重(zhong)要意義(yi)。時間定(ding)(ding)額(e)由以下幾個部(bu)分組成(cheng)：
（1）基本時間
（2）輔助時間
（3）布置工作地時間
（4）休息和(he)生理需要時(shi)間
（5）準備與終(zhong)結時間
（二）提高生產率的工藝途徑
勞動生(sheng)(sheng)(sheng)產(chan)率(lv)(lv)是以工人在單位時間(jian)內所(suo)生(sheng)(sheng)(sheng)產(chan)的(de)合格(ge)產(chan)品的(de)數量來(lai)評定(ding)的(de)。不(bu)斷提高勞動生(sheng)(sheng)(sheng)產(chan)率(lv)(lv)是降(jiang)低成本、增加積累和擴大(da)社會再生(sheng)(sheng)(sheng)產(chan)的(de)根本途(tu)徑。提高勞動生(sheng)(sheng)(sheng)產(chan)率(lv)(lv)是一個與(yu)產(chan)品設(she)計、制造工藝、組織管理等都有關的(de)綜(zong)合性任務，此處(chu)僅就提高生(sheng)(sheng)(sheng)產(chan)率(lv)(lv)的(de)工藝途(tu)徑作一簡(jian)要說明(ming)。
1.縮減(jian)基本(ben)時間的工(gong)藝途徑
（1）提(ti)高切削用量
（2）縮減工作行程長度
（3）多件加工
2.縮減輔(fu)助時(shi)間(jian)的工藝途徑
（1）直接縮減輔助時(shi)間
（2）將輔助時間與基本時間重合
3.縮減布置工作地時間(jian)
4.縮減準(zhun)備終結時(shi)間
1）運用成組工藝(yi)原理(li)
2）采用(yong)可換(huan)刀架(jia)或刀夾
3）采用刀(dao)具微(wei)調和快調機構
4）采用(yong)數控加(jia)工過(guo)程擬實技術
所謂經濟分析就(jiu)是(shi)通過比較(jiao)各種不同(tong)工藝(yi)方案的(de)生(sheng)產成本(ben)，選出其中最為經濟的(de)加(jia)工
方案。生(sheng)產成本包括兩部分(fen)費用，一(yi)部分(fen)費用與工藝(yi)過程(cheng)直接有關，另一(yi)部分(fen)費用與工藝(yi)
過程不(bu)直接有關(guan)（例如行政(zheng)人員工資、廠房折舊費、照明費、采暖費等）。與工藝過程直接
有關的(de)費用(yong)稱為工(gong)藝(yi)成(cheng)本(ben)，工(gong)藝(yi)成(cheng)本(ben)約占零(ling)件生產成(cheng)本(ben)的(de)70%~75%。
（一）工藝成本的組成及計算
工藝成(cheng)(cheng)本由可變費用與不變費用兩部分組(zu)成(cheng)(cheng)。
（二）工藝方案的經濟評比
對(dui)幾種(zhong)(zhong)不同工藝方案進行經(jing)濟評比時(shi)，有(you)以下兩種(zhong)(zhong)不同情況：
1．當需評比的(de)工藝方案均采用(yong)現有設備或其(qi)(qi)基本(ben)投資相近時，可用(yong)工藝成本(ben)評比其(qi)(qi)優劣。
（1）兩加工(gong)方案中少數工(gong)序不(bu)同(tong)，多數工(gong)序相同(tong)時，可通過計(ji)算少數不(bu)同(tong)工(gong)序的單(dan)件成本St1與St2進行(xing)評(ping)比。
（2）兩加(jia)工方案中(zhong)，多數工序不(bu)同(tong)，少數工序相(xiang)同(tong)時，則(ze)以該零件(jian)加(jia)工全(quan)年工藝(yi)成本S1與S2進(jin)行比較。
2.兩種工(gong)藝方案的基本投(tou)資差(cha)額較大時(shi)，則(ze)在考慮(lv)工(gong)藝成本的同(tong)時(shi)，還要考慮(lv)基本投(tou)資差(cha)額的回收期限。
投資(zi)回(hui)收期必須滿(man)足以下(xia)要求：
1）回收期(qi)限(xian)應小(xiao)于專用設備或工藝裝備的使用年限(xian)；
2）回收期限(xian)應小于該產品的市場壽命（年）；
3）回(hui)收(shou)期限應小于國家所規定的標(biao)(biao)準(zhun)回(hui)收(shou)期，采用(yong)專用(yong)工藝(yi)裝備的標(biao)(biao)準(zhun)回(hui)收(shou)期為2-3年(nian)，采用(yong)專用(yong)機床的標(biao)(biao)準(zhun)回(hui)收(shou)期為4-6年(nian)。