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外文翻译方飞
大连交通大学信息工程学院
毕业设计(论文)外文翻译
学生姓名方飞 专业班级机械茅10-2
指导教师赵永成职称 教授
所在单位机械工程系机制教研室
教研室主任 董淑婧
完成日期年月日
Gasturbines-agrowthindustry
Majordevelopmentsinthefiledofgasturbinetechnologyhavetakenplaceinrecentyearsandpowerunitsareavailabletodaythatcompetewithdieselenginesinawiderangeofapplicationsfromsmallenginesforboats,cars,lightaircraftandtruckstolargeunitsforindustrialandelectricalgeneratingstations.Forsimilaroutput,gasturbineshavetheadvantagesofproducinglessnoiseanddischarginglesspollution,factorsthatcouldbecomeincreasinglysignificantwiththegrowingawarenessoftheneedtoprotecttheenvironment.Latestresearchsuggeststhatthegasturbinesarealsocapableofmoreefficientoperationthantheirrivals.
Acompanyrapidlygainingaworld-widereputationforitspioneerworkonadvancedconceptpowerpantsisnoelPennyTurbinesLtd,SouthamandHarwich.Thefounderandmanagingdirector,noelpenny,hasahighpersonalinternationalreputationasanauthorityonsmallgasturbine.Althoughthecompanywasestablishedasrecentlyas1972,noelpennyandmanyofhisseniorengineersalreadyhadmanyyearsofexperience,inparticularwiththedesign,developmentandproductionofsmallindustrialandautomotivegasturbineatroverfrom1950onwards.Unitsproducedweresuccessfullyusedtodrivepumps,generators,processplants,andhovercraftauxiliaries,etcandlateradairborneauxiliarypowerunitsinsuchaircraftasVulcan,Argosy,NimrodandHarrier.
NoelPennyTurbinesLtd,isorganizedinthreebasicdivisions,powerplantengineering,researchanddevelopment,andmanufacturing.
Inpowerplantengineering,thecompanycarriesoutresearch,designanddevelopmentintoadvancedconceptunitstomeettherequirementsoftheworld’smarkets.Researchanddevelopmentiscarriesoutbothforthecompany’sownrangeofproductsandundercontractforclientwhowillultimatelymanufacturetheirownrange.Inmanydevelopments,majorfactorstakenintoconsiderationarecost,efficiencyandeaseofproduction.Plantavailablein-houseincludesequipmentforrigandengineevaluationupto1000hp,whilecloseliaisonwithmajorGovernmentResearchEstablishmentsandUniversitiesprovidesaccesstosophisticatedfacilitieswhereonlyintermittentusageisrequired.
Thecompanyrecognizestheimportanceoftrainingthenextgenerationofengineersinthesubjectofgasturbinetechnologyandthermodynamics,andhasdevelopedtheNPTTurbojetinstructionalset.ThisisbasedontheNPT401engine,whichisdown-ratedto2501bthrustwithafullyvariablethrottlerangefromidlingtomaximumpower.Anelectroniccontrolprotectsagainstmisuseandprovidesafail-safesystem.
Theengineispivotedinatubularsteelframewithathrustmeasuringcapsuleincorporatesinthelinkage.Temperatureandpressureprobesateachsectionoftheengineareconnectedtothreeabutmentplatesontheframetofacilitatepipingandwiringtoacontrol/instrumentconsole.Threealternativepropulsionnozzlesareprovidedtoenablethestudenttoexploreawiderangeofoperatingcharacteristics.
Anindicationofthecompany’sstandinginthefieldofmaterialsandthermodynamicsresearchisthepossessionoftwohundredworldpatentscoveringseveralareasofhightemperaturetechnology.Inalltheseactivitiesthebasicaimistoimprovethepracticaloperationofthecompany’sproducts.
ThemanufacturingdivisionhastheabilitytoproducehighqualitycomponentsandthecapabilitybothtomeettherequirementsofNoelPennyTurbinesLtdandtocarryoutsubcontractworkforclients.Machineshops,sheetmetalworking,weldingandassemblyshopsaregearedtoprototypeandsmallbatchproductionofprecisioncomponentsandsub-assemblies.
Stringentqualitycontrolandinspectionstandardsensurethatclosetolerancesandhighsurfacefinishesaremaintained.ThesearrangementsarefullyapprovedbytheBritishMinistryofDefenceQualityAssuranceBoardtotheconditionofDEF-STAN05.21.
Thecompanyiscontinuallyreplacingandupdatingitsmachinetoolstokeepabreastofproductdevelopmentsandthegrowingneedsformachiningstainlesssteels,Nimonicsandotherhightemperaturealloys.
IncludedinthemachineshopatCoventryarethreeHerbert/DevliegJigmils,onemanuallyoperatedandtwowithTape/Dialincontrol,usedforprecisionmachiningofawiderangeofcomponentsincludingcylinderblocks,gearboxesandcasingsincastiron,steelandNimonics.AlltheJigmilsarefittedwithindexingtablestoallowthemaximumamountofmachiningatasinglesetting.Thinnotonlyreducestheoverallproductiontimebuthelpstoensureanaccuraterelationshipbetweenboresandadjacentfaces.
Afeatureoftheeightcylinder,V-typeblockinfigs.2and3isthecrankshaftboreinwhichthecylinderblockisincastironandthebearingcapsareinsteel.Theseareboredaccuratelyinlinefrombothendsoftheblockwitha180°tableindexbetweenoperations.Thetwocamshaftboresaremachinedinasimilarway.Thecompletemachiningcycleincludesmultiplemilling,boring,drillingandtappingoperationsandeachcylinderblockrequiresanoverallcycletimeof180hours.
Figs.4and5showa4-cylinderin-lineblockbeingmachinedonaHerbert/DeVlieg2B-36Jigmil,whileFig.6showsacylinderheadthatwaspreviouslymachinedonthisJigmil.
ThehistoryofNoelPennyTurbinesLtdisoneofcontinuousgrowththroughsoundengineeringdevelopmentandproductionofaproductthatisbeingincreasinglyacceptedadasolutiontomanyoftomorrow’spowerrequirements.
Electronicgaugingindicatorwithdigitalreadout
AsingledimensionelectronicgaugingindicatorwithdigitalreadouthasbeenintroducedbyHerbertSigmaLtd.
Availableforinch/metricindication,thisnewindicatoroperatedwithanyoftheSigmaseriesoflineardisplacementtransducersandgaugingheadstochecksuchfeaturesaslength,diameter,thickness,taper,squarenessandout-of-round.
Itisavailablewithachoiceofmeasuringranges:
±2.0㎜or±0.2㎜and0.2inchor±0.02inchreadingto0.001㎜and0.0001inchonthelongerrangesand0.001㎜and0.0001inchonthehighermagnificationranges.
DigitalreadoutisprovidedbyaredLEDdisplayfeaturing10㎜highnumerals.Signalslampsarefittedforplus(yellow),minus(red),andOK(green)toleranceindication.
Theinstrumentprovidesfacilitiesforsingletransducerorfortwotransducerslinkedinsumordifferencemode,whilestandardanaloguevolt-ageandcurrentoutputsareviaa12pinsocket.
MTIRAopendays
Morethan400visitorssawsome34representativeexhibitsanddemonstrationswhentheMachineToolIndustryResearchAssociationatMacclesfieldopeneditsdoorslastmonthtoshowprogressinmachine-tooltechnology.
Severaldemonstrationsreflectedworkonimprovingsafetyandinreducingthelevelsofnoisegeneratedbymachinetoolsandincludedrecordingsofthenoiselevelsemittedbyamachinebeforeandafternoisereductiontreatment,givingagraphicillustrationofthevalueofthetechniquesdeveloped.
TheAssociationalsoshowedaseriesofrigsfortestingawidevarietyofguardsandguardingmaterials.Thegrindingwheelguardtestrigandthehigh-energymissilerigaremassivestructuresandthewholecomplexconstitutesauniqueresourceintheUKforthetestingofguards.
TheAssociation’sworkindevelopingvariouscomputer–baseddesigntechniquesandphysicalmodelingtechniquesishelpingtoexploitthecapabilitiesofimprovedcuttingtoolsandmethods.
Sometimestheperformanceofmachinetoolsfallsshortoftheexpectationsofmanufacturersorusersan`theAssociationisnowskilledintheroleoftechnologicaldetectiveworkinidentifyingthecausesoftheproblemandinrecommendingremedialaction.
MTIRAhasaccesstoworld-widedatabaseswhichallowsittooffermembersaninformationandadvisoryserviceandisalso,onmanyoccasions,abletohelpnon-members.
Prop-shaftcentrequickturnround
Commercial-vehicle,propeller-shaftassembliesofanydiameterandtorqueratingcanbelengthened,shortened,re-tubedorsuppliedcompletebyTricentrolChassisDevelopmentsLtdatitsProp-shaftCentreatDunstable.
Newequipmentforwelding,tubealignmentandbalancinghasbeeninstalled,enablingtheCentretogivevehicleoperators’repairersandevenchassismanufacturersamaximum36hourturnaroundonmosttypesofshaftupto6in(150㎜)diameter,whetherofHardy-Spicerorcontinentalpattern.
Investmentintheequipmentfortheproductionandmodificationofprop-shaftstooriginalequipmentstandardsfollowedfromthegrowingvolumeofbusinessforchassiswheelbasealterationsandinstallationofTelmaretarders(whichalwaysentailsshorteningthevehicle’sprop-shaft).
ThenewplantcomprisesaGKNLincolnelectricCO2arc-weldinginstallation,couples(onthesameworked)toaspecialMillstube-alignmentpresssuppliedbyAlfredHerbertLtd.
The30-tonverticalpresscanbeusedforstraighteningexistingornewstockprop-shafttubemisalignmentstowithin0.003inoverthewholelength.
Weldingofthetubeendstotheuniversal-jointassembliesisautomated;theweldfeedisgearedtothespeedofrotationoftheshafttogiveaneven,high-qualityweldseamaroundtheshaftcircumferenceandanautomaticcut-offatthecompletionof360°rotation.
Theneedforalignmentcorrectionisoftenindicatedbywhirlingforcesshownuponthecentre’sdynamicbalancingmachine.
Shaftupto9ft(2.74m)longcanbeaccommodated.ItisexpectedthattheProp-shaftCentrewillalsobewidelyusedforhandlingnon-automotivedriveshafts,suchasthoseusedforpoweringin