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1、Mechanicalmanufacturingt echnologyEconomicanalysiso fpr ocessTimequotaThetimer equir edt opr oduceapr oductorcomplet eapr ocessundercer tainpr oductionconditionsu definitionu for mBasic time:the time r equir ed t o dir ectly change the natur e o f the pr oduction object t o mak e it aqualifiedpr odu
2、ctormeetther equir ementso fthepr ocess(includingthecutinandcutouttime)Auxiliar y time:all kinds o f auxiliar y action time that must be carried out in or der t o r ealize the pr ocess,such as lo ading and unlo ading w orkpieces,star ting and st opping the machine t ool,changing thecuttingamount,adv
3、 ancingandr etr eatingthecutt er,et cArrange the w orking time:including changing t ools,lubricating machine t ools,cleaning chips,cleaningt ools,et c.Time for r est and physiological needs:the time r equir ed for w ork er s t o r ecov er physical str ength andmeetphysiologicalneedsinthew orkshif tP
4、r ep aration end time:familiar with pr ocess documents,r eceiving blanks,installing clamps,adjustingmachinet ools,sendingfinishedpr oducts,et cu Singletimeandsinglemanhourquotacalculationl Singletime:l W orkquotao fsinglepiece:wher e tB b asictime tA auxiliar ytime tC timeo fw orkingplacearrangement
5、 tR timer equir edforr estandphysiology tP Pr ep arationendtime B b at ch（5-27）（5-28）T echnologicalappr o achest oimpr ov epr oductionefficiencyu R educeb asetime:Impr ov ethecuttingp aramet er s(cuttingspeed,feed,cuttingdepth,et c.);Adopt multi cutt er and multi edge for machining(such as milling i
6、nst ead o fplaning,usingcombinationcutt er,et c.);Adopt compound w orking st eps t o mak e the b asic time o f multiple sur facemachiningcoincide(suchasmulticutt ermachining,multipiecemachining,et c.).Figur e5-52multit ooltur ningFigur e5-53millingplaneo fcombinedmillingcutt erTb=L ZnfapMultiplepr o
7、cessingFigur e5-54multiaxiscombineddrillingmachineFigur e5-55gearseriesmachiningu R educeauxiliar ytime:Mechanization and aut omation o f auxiliar y actions(such as aut omatic lo adingandunlo adingdevice,adv ancedfixtur e,aut omaticmeasuringdevice,et c.)Mak e the auxiliar y time ov erlap with the b
8、asic time(such as using multi fixtur e or multi table;using onlinemeasur ement,et c.)Figur e5-57transpositionpr ocessingFigur e5-56aut omaticmeasur ementu R educethetimet oarrangethew orkingplace:R educet oolchangetimeandt ooladjustmenttime Adoptaut omatict oolchangedeviceorrapidt oolchangedevice Us
9、enonr egrindingt ool Uset emplat eort oolsettingblockfort oolsettingoraut omatict oolsetting Usingnewt oolmat erialst oimpr ov et ooldurabilityu R educepr ep arationendtime:Usinggr oupt echnologyandgr oupfixtur einsmallandmediumb at chpr oduction InNCmachining,o ff-linepr ogrammingandmachiningpr oce
10、sssimulationt echnologyar eused Figur e5-59lasert oolsettingR eal R ealFigur e5-58nor egrindingt oolPr ocesscostl Pr oduction cost the sum o f the expenses r equir ed t o pr oduce a pr oduct orap ar tl Pr ocesscost thep ar to fpr oductioncostdir ectlyr elat edt opr ocessl Thepr ocesscostcanbedivided
11、int otw op ar ts:u V ariableexpensesExpenses r elat ed t o and pr opor tional t o annual output ar e r ecor ded as CV,includingmat erial costCVM,wage and wage sur char ges o f machine t ool w ork er sCVP,machine t ooluse cost CVE,depr eciation cost CVD o f general machine t ool,cutting t ool cost CV
12、C,depr eciationcostCVFo fgeneralfixtur e,et cCV=CVM+CVP+CVE+CVD+CVC+CVF（5-29）u ConstantcostExpenses not dir ectly r elat ed t o the change o f annual pr oduction ar e r ecor ded as CN.Including adjustment o f w ork er s wages and wage sur char gesCSP,depr eciation o f specialmachinet oolsCSD,depr ec
13、iationo fspecialclampsCSF,et cCN=CSP+CSD+CSF（6-30）u Annualpr ocesscosto fp ar ts(wher e N istheannualoutputo fp ar ts):u Pr ocesscosto fsinglep ar t:CY=CV N+CN（5-31）CP=CV+CN/N（5-32）Pr ocessplancomp arisonu Comp ar epr ocesscostsExisting equipment or similar b asic inv estment shall be used for the p
14、r ocessscheme t o be ev aluat ed,and the pr ocess cost shall be dir ectly comp ar ed.Thecritical annual pr oduction NC(Figur e 5-61)o f each scheme is calculat ed asfollows:（5-33）Figur e5-61comp arisono fannualpr ocesscostandcriticalannualpr oduction0programme 1CN 1CN 2NCNCYprogramme 2u Comp arativ
15、ep ayb ackperiodu Criticalannualpr oductionNC Cconsideringp ayb ackperiod(Figur e5-62)When ther e is a lar ge differ ence betw een the b asic inv estment amount o f differ entpr ocess schemes,the p ayb ack period o f the b asic inv estment amount o f differ entschemesshouldbeconsider ed.（5-34）（5-35）pr ogramme 1CN1CN20NCNCYpr ogramme 2CYNC CFigur e5-62criticalannualpr oductionconsideringadditionalinv estment inv estmentp ayb ackperiod;F b asic inv estmentdiffer ence;S annual pr oduction costsavings.wher eThanksforwat ching