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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