汽机培训2(喀北电站概述)

喀北电站汽机概述Turbineoverview喀北电站汽机图片turbinepicture汽机主机的结构概述Generaldescriptionofmainunitstructure

汽轮机的结构组成：

Compositionofsteamturbine

静止部分：包括汽缸、喷嘴、隔板、隔板套、汽封及轴承等部件；Staticparts:includingcasing,nozzle,diaphragm,diaphragmsleeve,glandsealandbearingsetc.转动部件：包括动叶片及转子（叶轮、主轴）联轴器、汽封等部件；Rotatingparts:includingmovingbladeandrotor(impeller,mainshaft),coupling,glandsealetc.附属设备：包括主汽阀、调节汽阀、调节系统、主油泵、辅助油泵及润滑装置等。Auxiliaryequipment:includingmainsteamvalve,adjustingsteamvalve,adjustingsystem,mainoilpump,auxiliaryoilpumpandlubricatingdeviceetc.主机的结构概述及性能参数汽缸casing隔板、汽封diaphragm,glandseal轴承shaftbearing转子rotor盘车turninggear汽缸、滑销系统汽缸是汽轮机的外壳。其作用是将进入汽轮机的蒸汽与大气隔开，形成蒸汽能量转换的封闭汽室；汽缸内部安装着隔板和隔板套、汽封等部件，外部与进汽、排汽及抽汽等管道相连接，因此还起着支承定位的作用。Casingistheshellofturbine.Itsfunctionistoseparatethesteamenteringintotheturbinefromatmosphere,formingthesealedsteamchamberwherethesteamenergycanbetransformed;thecomponentssuchasdiaphragmandbladecarrieretc.areinstalledinthecasing,thepipessuchassteamadmissionpipe,exhaustpipeandextractionpipeareconnectedtotheexteriorpartofcasing,therefore,italsoplaystheroleofsupportingandpositioning.高压汽缸为单层缸隔板套结构，由高压缸前部和高压缸后部两部分组成。前部由耐热合金ZG20CrMoV浇铸而成，后部由碳钢ZG230～450浇铸而成，两部分通过垂直法兰用螺栓连接起来，高压缸前部采用高窄法兰，取消法兰加热装置，有利于机组快速启停。TheHPcasingissinglelayerbladecarrierstructure,itconsistsofthefrontpartandrearpart.ThefrontpartisforgedbyheatresistantalloyZG20CrMoV,therearpartiscastedwithmildsteelZG230～450.thesetwopartsareconnectedtogetherthroughverticalflangewithblots,thefrontpartofPhcasingadoptshighnarrowflange,theheatingdeviceshouldberemoved,whichisfavorablefortheshutdownandstartupofunitwithfastspeed.高压缸前部有四个蒸汽室，与汽缸焊成一体，每个蒸汽室内装有一只调节阀，四个调节阀各自控制着一组喷嘴。每个调节阀由一个调节阀操纵座控制其开度。新汽通过主汽阀后，由四根主汽管分别引入四个高压调节阀，由调节阀控制进入高压缸的蒸汽流量。高压缸排汽通过位于汽缸上方的两根连通管进入低压缸。进入低压缸的蒸汽对称地向前后两个方向流动，在通流部分膨胀做功之后，经过低压缸扩压管排入排汽装置。Therearefoursteamchambersinfrontofcasing，whichareweldedintegrallywithcasing,eachairchamberisequippedwithacontrolvalve,theindividualcontrolvalvescontrolsagroupofnozzlerespectively.Acontrolpedestalofcontrolvalvecontrolstheopeningofacontrolvalve.Afterpassingthroughthemainstopvalve,thefreshsteamisintroducedintoHPcontrolvalvebyfourmainsteampipes,thesteamenteringintoHPcasingiscontrolledbycontrolvalve.TheexhaustedsteamfromHPcasingentersintoLPcasingthroughtwoconnectingtubeslocatedonthetopofcasing.ThesteamenteredintoLPcasingflowsforwardandbackwardsymmetrically,afterexpandingtoworkintheadmissionpassage.ThesteamwillbedischargedintoexhaustdevicethroughdiffusertubeofLPcasing.低压缸为双流式，轴承箱落地。该缸为双层，外缸为钢板焊接，由三段组成，内缸为小段铸件及钢板焊接而成。内缸以键定位，两脚搁在外缸内侧的支撑面上，外缸支撑在基架上。外缸与轴承座间在下半设有立键。高低压缸连通管与低压内外缸靠波纹管相联，满足既能密封又能自由膨胀的要求。LPcasingisdoubleflow,itsbearingboxisgroundingarranged.Thiscasingisalsooftoolayers,theexteriorcasingisweldedwithstealboard,andcomposedofthreestages,theinteriorcasingisweldedwithshortcastingandsteelboard.Interiorcasingispositionedbykeys,itstwofeetisplacedonthesupportingsurfaceontheinternalsideofexteriorcasing,exteriorcasingissupportedontheframe.betweentheexteriorcasingandbearingpedestal,theverticalpinissetonlowerpart.TheconnectingtubeofIPcasingandLPcasingisconnectedwiththeexteriorandinteriorLPcasingbybellow.Whichcanmeettherequirementofsealingandfreeexpansion.汽轮机在启动、停机和工况变化时，温度发生变化，将产生膨胀或收缩。为了保证汽缸受热或冷却后以正确的方向膨胀或收缩，并保持汽缸与转子中心一致，设置了一套滑销系统。滑销系统通常由横销、纵销、立销等组成。Duringthestartup,shutdownandchangingofworkcondition,thetemperaturechanges,theturbinewillexpandorshrink.Inordertoensurethatturbinecanexpandorshrinkintherightdirectionwhenitisheatedorcooled,andthecenterofcasingandthatofrotorcomplywitheachother,asetofslidingpinsystemisestablished.Theslidingpinsystemconsistsoftransversepin,longitudinalpinandverticalpinetc,thestructureofeveryslidingpinisasfig.6—10show.该机组采用双死点滑销系统，一个死点位于中箱底部，一个死点位于低压进汽中心线上。高压缸前后各两个猫爪，分面支撑在前轴承箱、中轴承箱上，中轴承箱采用传统的猫爪-横键，前轴承箱采用推拉杆结构。Thisunitadoptstheslidingpinsystemwithdoubledeadpoints,onedeadpointislocatedonthebottomofintermediatebox,theotheroneissituatedontheLPsteamintakecenterline.TherearetwocatclawsonfrontandrearpartofHPcasingrespectively.Whicharesupportedonthefrontbearingboxandintermediatebearingbox,theintermediatebearingboxadoptstraditionalcatclaw-transversekey,thefrontbearingboxadoptsthepushpullrodstructure.转子(高中压缸转子)rotor(HIPcasingrotor)转子（低压缸转子）rotor(LPcasingrotor)高中压转子与低压转子均为整锻结构。高压转子材料30Cr1Mo1V，低压转子材料30Cr2Ni4MoV。HIProtorandLProtorareallintegralforgedrotor.MaterialofHIProtoris30Cr1Mo1V,materialofLProtoris30Cr2Ni4MoV.汽轮机各转子之间以及汽轮机转子与发电机转子之间均用联轴器连接，用以传递扭矩和轴向力。Usecouplingstoconnectrotorsofasteamturbine,aswellasrotorsofsteamturbineandrotorsofgenerator,whichistotransfertorqueandaxialforce.隔板diaphragm隔板和汽封diaphragmandglandseal隔板用来固定静叶片，并将汽缸内分隔成若干个汽室。为了安装与拆卸方便，隔板通常做成水平对分形式。隔板内圆孔处开有汽封安装槽，用来安装隔板汽封，减小隔板漏汽损失。Thediaphragmisusedtofixthestationaryblade,anddividethecasingintoseveralsteamchambers.Inordertoassembleanddisassembleiteasily.Thediaphragmisusuallydividedintotwopartshorizontally.thesealinginstallationslotissetintheorificeinthediaphragm,whichisusedtoinstalldiaphragmseal,reducethelossofsteamleakage.冲动式汽轮机的隔板主要由静叶片、隔板体和隔板外缘组成，主要形式有焊接式和铸造式两种。Thediaphragmofactionturbineconsistsofstationaryblade,diaphragmproperanddiaphragmperiphery,themainformincludeweldingconnectionandcastingtwokinds.汽轮机有静子和转子两大部分。运行时，转子高速旋转，而静子固定不动。因此，转子与静子之间必须保持一定的间隙，才能不使它们相互碰撞和磨擦。Asteamturbinehasstatorsandrotors.Whileitruns,rotorsrotateathighspeed,andstatorskeepstill.Therefore,thereshouldbecertainspacebetweenarotorandastatorinthepurposeofavoidingcrashandfriction.蒸汽流过汽轮机各级工作时，压力、温度逐级下降，在隔板两侧存在着压差。当动叶有反击度时，动叶片前后也存在压差。Whensteamflowsthrougheverystagetowork,itspressureandtemperaturedescendstagebystage,sothereispressuredifferencebetweentwosidesofthediaphragm.Whenmovingbladehasreactiondegree,thereisalsopressuredifferencebetweenitsfrontpartandbackpart.蒸汽除了绝大部分从导叶、动叶的通道中流过作功外，一小部分将会从各处间隙中流过而不作功，成为一种损失，降低了汽轮机的效率。转子必须穿出汽缸，支承在轴承上，此处也必然要留有间隙。Mostofthesteamworkswhenflowingthroughpassagesofguidebladesandmovingblades,butasmallpartofitflowsthroughclearanceswhichisalossandreducesefficiencyoftheturbine.Therotorsmustcomeoutcasingandbesupportedbythebearing,andthentheremustbeclearance.对于高压缸的两端和中压缸的前端，汽缸内蒸汽压力大于外界大气压力，蒸汽将会向外漏出，降低了效率，并造成部分凝结水损失。在中压缸的排汽端及低压缸的两端，因汽缸内的蒸汽压力低于外界大气压力，在主轴穿出汽缸处的间隙中，将会有空气漏入汽缸内。AtthebothendsofHPcasingandthefrontendofIPcasing,pressureofsteaminthecasingislargerthanthatoutside,thussteamwouldleakoutwhichreducesefficiencyofthesteamturbineandcausespartofcondensateloss.AtexhaustendofIPcasingandbothendsofLPcasing,becausepressureofsteaminthecasingislowerthatoutside,whenmainshaftcomesoutoftheclearanceonthecasing,someairwouldgetinthecasing.由于空气在凝汽器中不能凝结，使汽轮机背压升高，降低了蒸汽的作功能力。为了减少上述各处间隙中的漏汽(或从外部漏入空气)，又要保证汽轮机正常安全运行，特设置了各种汽封。这些汽封可分为通流部分汽封、隔板汽封和汽缸前后汽封(也称轴封)三大类。但从工作原理来说，这三类汽封都属于迷宫式汽封。Asaircannotcoagulateincondenser,backpressureofthesteamturbinerises,whichreducesworkingabilityofthesteam.Inordertoreducesteamleakagementionedabove(orairoutsidegettingin),aswellasensurenormalrunningofthesteamturbine,allkindsofsealsteamsareset.Thesessealsteamscanbeclassifiedintothreekinds:flowsectionseal,diaphragmseal,aswellascasingfrontandbackseals(whichisalsocalledglandseal).However,basedonworkingtheory,allthethreekindsofsealsteamsbelongtolabyrinthseal.Thediaphragmsealandtheflowsectionsealareshowedinfigure。N110型汽轮机高压端部汽封及所有高压隔板汽封采用梳齿式汽封，低压端部汽封及隔板汽封采用斜平齿汽封。设计时采用了较大的轴向间隙和较小的径向间隙，减少漏汽损失，提高机组效率。ThesteamsealofthehighpressureendandallthehighpressurediaphragmsteamsealofN110typeturbineadopttheserrate-typesteamsealwhilethesteamsealoflowpressureendandthediaphragmsteamsealadopttheslantingandflatteethsteamseal.Thebiggeraxialclearanceandsmallerradialclearanceareadoptedduringdesigntoreducethesteamleakagelossandimprovetheunitefficiency.隔板与动叶根部间的汽封齿采用径向汽封，径向汽封的间隙可以很小，一般为0.5mm，同时可以具有较大的轴向间隙，可以适应机组快速起停的需要。Thesteamsealteethbetweenthediaphragmandthemovingbladerootareadoptedtheradialsteamsealwhoseclearancecanbeverysmallandusuallyisabout0.5mm.Meanwhile,biggeraxialclearancecanexist,whichcanmeettheneedsofquickstartupandshutdownoftheunit.动叶叶顶汽封为三至四片，降低漏汽损失。Thesteamsealonthetopofthemovingbladearethreetofourpieces,whichistodecreasethesteamleakageloss.轴承shaftbearing汽轮机的轴承有推力轴承和支持轴承两种类型。支持轴承的作用是承担转子的重量及转子不平衡质量产生的离心力，并确定转子的径向位置，保证转子中心与汽缸中心一致，以保持转子与静止部分间正确的径向间隙；推力轴承的作用是承受转子上未平衡的轴向推力，并确定转子的轴向位置，以保证动、静部分间正确的轴向间隙。Theturbinebearinghastwotypesasthrustbearingandjournal-bearing.Thefunctionofjournal-bearingistobeartheweightoftherotorandthecentrifugalforceproducedbecauseoftheimbalanceoftherotor,andfixontheradialpositionoftherotorandensuretherotorcenterisconsistenttothecasingcentersoastokeepthecorrectradialclearancebetweentherotorandthestationarypart;thefunctionofthethrustbearingistobeartheaxialthrustthathasn’tbeenbalancedontherotor,andfixontheaxialpositionoftherotorsoastoensurethecorrectaxialclearancebetweenthemovingpartandthestationarypart.汽轮机转子重量及轴向推力都很大，且转子的转速很高，轴承在高速重载条件下工作。因此，汽轮机轴承都采用液体摩擦的滑动轴承。工作时，在轴颈和轴瓦之间形成油膜，建立液体摩擦，以保证机组安全平稳地工作。Theweightoftherotoroftheturbineisveryheavy;theaxialthrustisverystrong;therotorspeedisveryhighandthebearingworksunderthehighpeedandheavyloadcondition.Therefore,theturbinebearingsarealladoptedtheslidingbearingwithliquidfriction.Duringworking,oilfilmsareformedbetweentheshaftneckandthebearingbushandtheliquidfrictionisestablishedsoastoensuretheunittoworksafelyandstably.汽轮机转子由四个支持轴承支持，其中1#轴承为推力-支持联合轴承，置于前轴承箱内，支持部分具有球面、可自位；推力部分为密切尔式。工作瓦和定位瓦各10块，瓦块为扇形，可摆动。每块工作瓦都装有WZPM2-001、Pt100型表面铂热电阻测量轴承合金温度。2#轴承与3#轴承置于中轴承箱内，装有WZPM2-001、Pt100型表面铂热电阻测量轴承合金温度。4#轴承置于后轴承箱内，装有WZPM2-001、Pt100型表面铂热电阻测量轴承合金温度。各轴承下瓦开有高压油顶起油孔供启动和停机盘车时顶起转子。前、中、后轴承箱为落地式钢板焊接结构，钢板材料Q235-A。后轴承箱回油口装有窥视管，开有观察窗，可直接观察油流情况。窥视管装有电接点双金属温度计及WZP2-221铂热电阻，可就地显示油温，及远传报警和控制。Therotorofthesteamturbineissupportedbyfoursupportingbearings.Thebearing1#isthrust-supportingjointbearingandisplacedinsidethefrontbearinghousing,whosesupportingparthassphereandcanself-align;andthrustpartisofMichelltype.Therearetenworkingbushesandlocatingbushesrespectively.Thepadisinsegmentalshapeandcanswing.EachworkingbushisinstalledwithasurfaceplatinumresistanceofWZPM2-001andPt100typemeasuringthetemperatureofthebearingalloy.Thebearing2#and3#areplacedinsidethemiddlebearinghousingandareinstalledwithasurfaceplatinumresistanceofWZPM2-001andPt10typemeasuringthetemperatureofthebearingalloy.Thebearing4#isplacedintherearbearinghousingandisinstalledwithasurfaceplatinumresistanceofWZPM2-00andPt100typemeasuringthetemperatureofthebearingalloy.Ajack-upoilholeofhighpressureoilisopenedunderthelowerbushofeachbearingtojacktherotorduringthestartup,shutdownandjigger.Thefront,middleandrearbearinghousingsareoffloor-typesteelplateweldingstructuresandthesteelplatematerialisQ235-A.Thereturnedoilinletoftherearbearinghousingisinstalledwithapeeptubeandanobservationwindowisopenedfordirectlyobservingtheoilflowstate.Thepeeptubeisequippedwithelectric-contactbimetalthermometerandtheWZP2-221platinumresistance,throughwhichtheoiltemperaturecanbeshownonthespot,thealarmcanbetransmittedremotelyandcontrolled.汽机主机部分steamturbinepart1.型号type：N110-8.83/535type2.形式：高温、高压、冲动式、双缸、双排汽、凝汽式2.structuretype:Hightemp.HP,impulsetype,dual-casing,dual-discharge,condensatetype3.额定功率ratedpower：110MW4.额定转速ratedspeed：3000r/min5.转向rotarydirection：从机头向发电机方向看顺时针clockwise(seefromturbinetogenerator)6.工作电网频率gridfrequency：50Hz7.额定进汽量ratedfeedsteam：401.01t/h8.最大进汽量Max.feedsteam：420t/h9.最大功率Max.power：114.96MW10.新汽压力livesteampressure：8.83MPa11.新汽温度livesteamtemp.：535℃12.额定背压ratedbackpressure：7.9KPa13.级数stages:1C+15P+2x6P（28stages）14.汽耗steamconsumption:3.646kg/kW.h15.热耗thermalconsumption:8997kJ/kW.h主油泵mainoilpump润滑油系统Lubeoilsystem主油泵mainoilpump主油泵入口mainoilpumpinletpressure0.11—0.14MP， 出口outletpressure1.4—1.65MP， 设计designpressure1.96MP,146150kg/h主油箱mainoiltank28.8m3(cubicmeter)立方米润滑油压lube.oilpressure0.18—0.19MP润滑油过滤器lube.oilfilterSPL150XB，，105.6t/h启动高压油泵startHPoilpumpSNH210R40E，2MP，321L/min电机motorYB160L—2，18.5KW,415V交流油泵出口ACoilpumpoutlet0.35MP，2700L/min,30KW,415V直流油泵出口DCoilpumpoutlet0.35MP，2700L/min,30KW,110V净化装置（固定）purificationdevice(stationarytype)QYJB-6，85L/min,55.49kw,415V,(移动）(portabletype)冷油器oilcoolerYL-2X120-15，120m2顶轴油泵jackingoilpump1971Kg/h,32MP,1500r/min,电机motor18.5KW，415V，1500r/min盘车turninggear4.6r/min,18.5KW,415V,730r/min冷油器oilcooler盘车turninggear在汽轮机不进蒸汽时驱动转子以一定转速旋转的设备称为盘车装置。其作用是：Theequipmentwhichdrivestherotorrotatesatcertainspeedwhenthereisnosteamenteringthesteamturbineiscalledturninggear,whosefunctionsare:1)在汽轮机冲转前和停机后使转子转动，以避免转子受热和冷却不均而产生热弯曲。在汽轮机启动过程中，为了使凝汽器内建立起一定的真空，需在冲转前向轴封供汽，由此进入汽缸的蒸汽滞留在汽缸的上部，使汽轮机上、下部分出现温差，若转子静止不动将向上弯曲，影响启动工作的正常进行，甚至引起动、静部件摩擦。Tomaketherotorrotatesbeforethesteamturbinerunningandaftershutdownsoastopreventtherotorfromproducingthermalbendingbecauseofunevenheatingandcoldness.Inthestartupprocessofthesteamturbine,itneedstosupplysteamtotheglandsealbeforetherunningsoastosetupcertainvacuuminsidethecondenser.Thesteamthatentersthecasingthroughthisplacestaysonthetopofthecasing,whichmakesthetemperaturedifferencesappearbetweentheupperpartandthelowerpartofthesteamturbine.Iftherotorkeepsstatic,itwillbendupward,whichinfluencesthenormalstartupworkandevenresultsinfrictionsbetweenactingcomponentsandstaticcomponents.停机时，汽轮机下缸比上缸冷却快，上、下部分之间也存在温差，如果转子停下后静止，将使大轴弯曲，这种弯曲需要较长时间才能消失，不利于汽轮机马上重新投入运行。Duringshutdown,thelowercasingofthesteamturbinecoolsmorequicklythantheuppercasingdoes.Therearetemperaturedifferencesbetweentheupperpartandthelowerpart.Iftherotorstopsandkeepsstatic,itwillmaketheshaftbend.Thiskindofbendneedsalongertimetodisappear,whichisbadforthesteamturbinetobeputintooperationagainquickly.2)启动前盘动转子，可以检查动静部件间是否有摩擦、润滑油系统工作是否正常及主轴弯曲是否过大等，用来检查汽轮机是否具备正常启动条件。2)toturntherotorbeforestartup,throughwhichcanexaminewhetherthereisanyfrictionbetweentheactingcomponentsandthestaticcomponents,whetherthelubricationoilsystemworksnormally,andwhetherthebendofthemainshaftistoolargeandsoon,andcancheckwhetherthesteamturbinehasthenormalstartupconditions.按盘车转速高低，盘车装置可分为高速盘车和低速盘车两种。采用高速盘车时转子转速(40～70)r/min，可以加快汽缸内的热交换，减小上、下缸之间及转子内部温差，缩短机组启停时间，并可以在轴承内较好的建立起油膜，保护轴颈和轴瓦。低速盘车时转子转速为(2～4)r/min，启动力矩小，冲击载荷小，有利于延长部件的使用寿命。按结构特点，盘车装置可分为具有螺旋轴的电动盘车、具有摆动齿轮的电动盘车及具有链轮——蜗轮蜗杆的电动盘车。

Accordingtothejiggerspeed,theturninggearcanbedividedintohighspeedjiggerandlowspeedjiggertwotypes.Whenadoptingthehighspeedjigger,therotorspeedis(40～70)r/min,whichcanspeeduptheheatexchangeinsidethecasing,decreasethetemperaturedifferencesbetweentheuppercasingandthelowercasingandinsidetherotor,shortentheunitstartuptimeandcanbettersetupoilfilmsinsidethebearingtoprotecttheshaftjournalandbearingbush.Therotorspeedis(2～4)r/minduringlowspeedjigger.Thestart-upmomentissmallandtheimpactloadislighter,whichisgoodforprolongtheuselifeofthecomponents.Accordingtothestructurefeatures,theturninggearcanbedividedaselectricjiggerwithscrewaxis,electricjiggerswithwobblegearandelectricjiggerwithchainwheels---worm-gear.本机组盘车装置安装在后轴承座盖上，为低速盘车装置。它既能手动盘车，又能电动盘车；既能手动投入，又能自动投入。Theturninggearofthisunitwhichisinstalledonthecoveroftherearbearingpedestalis