英文翻譯第1頁(yè)DeepslotmillingwithalargesidecutterboostsrotormachiningproductivitySuper-High-RigidityHF-5MMulti-Center(BridgeTypeMachiningCenter)1.BackgroundtoIntroductionofHF-5MShimada:ThankyouforpurchasingSNKsHF-5MMulti-Center.Themachinewasinstalledthisyear.Firstofall,couldyouexplainthecircumstancesthatledtotheintroductionoftheHF-5M?Aida:InJuly2000,Meidensha,HitachiandFujiElectricestablishedajointventure,JapanMotor&GeneratorCo.,Ltd.,wherethethreecompaniesagreedonatie-upforthemanufactureofsmallgenerators.ThemissionofJM&Gistoprovidecustomerswithhigh-quality,high-performanceproductsinacost-efficientandtimelymanner.Tothisend,JM&Gcombinesthestrengthsofthetechnology,know-howandhumanresourcesofthecompanies.MeidenshaalsohadtoupgradeitsproductionfacilitiesbecausethecompanyhadbeenselectedasapartnerofGEAeroEnergyProducts,amajorsubsidiaryofGeneralElectricCompany.Shimada:DoesthatmeanthatthenewlyinstalledSNKmachineinnotamereadditiontoexistingmachinetools?Imean,themachineissupposedtofulfillanumberofpurposes,isntit?Aida:InstalledpowergenerationcapacityintheUnitedstateshasbecomeinadequateinrecentyears.Tocopewiththesituation,variousactions,includingtheliberalizationofthepowermarket,havebeentaken.Underthesecircumstances,demandforgeneratorshasgrownsuddenly.Asageneratormanufacture,GEtriedtomeetthedemand,butitwasnecessarytoincreaseitsproductioncapability.(1)Thefirstgoalistoreduceman-andmachine-hourrequirement(increasingproductivityby60percent).Thisrequiresustodramaticallyimprovemachining英文翻譯第2頁(yè)conditionsandestablishproductiontechnology.(2)Thesecondgoalistoshortenmachiningleadtime(reducingmachiningleadtimebyhalf).Thisrequiresustostreamlinemachiningprocessesandeliminatetheneedtomoveworkpiecesfrommachinetomachine.Toachievethesegoals,wesetthreerequirementsforthenewproductionfacility.(1)Thefirstrequirementisashortertimetodeliverytomeetrapidlygrowingdemand.(2)Thesecondrequirementisamachinetoolcapableofheavycutstoincreaseproductivity.Thisrequirementmustbemettoensurehighmechanicalrigidityandreliability.(3)Thethirdrequirementistheenhancementofautomation-orientedfeaturetoincreaseuptimeandmetalremovalrates.2.Whatsageneratorrotor?Shimada:Beforegoingintodetailsofthenewmachinetool,wouldyouexplainthe“generatorrotor”,whichistheprincipalworpiecetobemachinedonthenewmachine?Aida:Therearemanytypesofgeneration,suchaswater-wheelgeneratorsandturbinegenerators.Forexample,ourgeneratorsystemcomposedofgeneratorsmanufacturedatourOhtaFactoryanddieselengineshaveanoutputrangeof20to1874KVA.Thesegeneratorsystemsarehighlyacclaimednotonlyasgeneral-purposebackupgeneratorsystems,butalsoasemergencydieselpowergeneratorsystems.Theyareinusemanypartsoftheword,includingvariesbuildinginJapanandtheShowastationinAmericaintheextremelycoldregion.Tomanufacturetheseproducts,ourfactoryisequippedwithtwo100-toncranes,largemachinetoolsincluding10-meterand7-meterlathes,andacleanroominwhichrotorwindingaremanufactured.Shimada:Ivebeentothefactorymyself,anditwasindeedequippedwithavarietyofmachinetools.Iwasreallyimpressedwiththehighaccuracyandqualityof英文翻譯第3頁(yè)largegeneratorpartsmachinedinthefactory.Ialsohadanopportunitytoseemanygeneratorsbeingmanufacturedthere.“Energetic”isthewordthatcametomindwhenIsawthefactory.Aida:Thankyou.Now,letmeexplainaboutrotorshafts,theworkpiecetobemachinedonournewmachinetool,takingabipolar,air-cooled,turbinegeneratorasanexample.Unlikethebackup/emergencygeneratorsIhavejustmentioned,thesegeneratorsconsistoflargegeneratorsmanufacturedatOhtaFactorywhicharedrivenbysteamorgasturbines.Thesegeneratorsarewidelyusedforindustrialandpowergenerationapplications.Standardgeneratingcapacityis75000KVAorless.Thepower-generatingpartofthegeneratorconsistsofastator,arotorandarotorbearing.Therotorisanassemblyofanironcoreandshaft.Tomakethingseasiertounderstand,letscallita“rotorshaft”.Shimada:Isee.How,then,doyoumanufacturearotorshaft?Aida:Arotorshaftiscarvedoutofaforgedlow-alloyblankthathasexcellentmagneticproperties.Majorstepsinthemanufacturingprocessare(1)turning,(2)slotmilling,drillingandtapping(milling),(3)grindingthebearings,(4)fittinginthecoils,and(5)balancing(finishturning)3.Useoffive-faceMachiningsystemShimada:Then,thenewlyinstalledHF-5Missupposedtobeusedforslotmilling,drillingandtappingoftherotorshaft.Wehearthatmanymanufacturersperformdeepslotmillingofrotorshaftonspecial-purposemachines.Why,then,didyouchooseourfive-facemachiningsystem?Aida:Ifwethinkonlyoftheslotmillingofrotorshafts,wecouldgowithaplanertypemachinetoolorwithalathe-basedhorizontalmachineequippedwithasidecutterspindlemountedonthecarriage.However,withaplanertypemachine,we英文翻譯第4頁(yè)cantexpecthighmachiningefficiency.AndwethoughtthatthesetypesofmachinescouldnotmeetourrequirementsImentionedattheoutset.Thereasonisthis.Therotorshafthasatotalof42deepslotscalledcoilslotsandventslot.Thedeepestslotsare27mmwideandabout140mmdeep.Thetotallengthofallslotsincludingshallowonesis105mperrotor.Deepslotmillingisthemosttime-consumingoperationinthemachiningprocess,andweusedtomachinethesedeepslotsinthreepassesperslot,usingaplano-millerequippedwithasidecutter.SowedecidedtouseaGerman-madesidecutterthatcanroughandfinishadeepslotinasinglepass.Tousethiscutter,however,weneededaspecial-purposemachinetoolrigidenoughtoendureheavycuts.Shimada:Youmentioned“heavycuts.”Howbigisthecuttingforceappliedtothatsidecutter?Aida:About20KNaccordingtothecuttingtoolmanufacturerscalculation.Thiscuttingforceisappliedtothecuttingedgeofthesidecutterthatis700mmindiameter.Conventionalmachinetoolsjustcanthandlethatmuchforce.Inordertoreducethenumberoftoolpassesfromthreetoone,itisnecessarytoincreasethemetalremovalratebyafactorofthreewithaforcethreetimesasdig