东汽轴封系统说明书

东汽轴封系统说明书密级：公司秘密ConfidentialClass:InternalDOCNO.(WBL)D660E-000155CSMDESIGNCHECKREVIEWAPPROVE换版记录Recordofrevision目录Contents序号No.章-节Chapter名称Description页数Pages备注Remarks10-1汽轮机自密封汽封系统说明书InstructionofSTSelf-sealingGlandSteamSystem200-1汽轮机自密封汽封系统说明书0-1InstructionofSTSelf-sealingGlandSteamSystem1.概述1.Generaldescription汽轮机汽封系统的主要作用是在汽轮机启动、运行、停机各种工况下，为端部轴封密封提供合适的汽源；引导并回收汽轮机轴端汽封及高、中压主汽门调节汽门阀杆的泄漏蒸汽及汽－气混合物，以防止蒸汽泄漏进入厂房；或大气中的空气漏入低压缸内，影响机组真空。Mainfunctionofthesteamturbineglandsteamsystemistosupplypropersteamfortheendshaftsealduringvariousoperationconditionsofsteamturbinestarting,operatingandshutdown,andtoguideandrecovertheleak-offsteamofthesteamturbineshaftendseal,HP,IPmainstopvalvestemandsteam–airmixture,soastopreventthesteamfromleakingintotheplantbuilding;ortheairinatmospherefromleakingintoLPcylindertoaffecttheunitvacuum.本机组汽封系统采用自密封汽封系统，即在机组正常运行时，由高、中压缸轴端汽封的漏汽经喷水减温后作为低压轴端汽封供汽的汽轮机汽封系统。多余漏汽经溢流站溢流至低压加热器或凝汽器。在机组启动或低负荷运行阶段，汽封供汽由外来蒸汽提供。该汽封系统从机组启动到满负荷运行，全过程均能按机组汽封供汽要求自动进行切换。此外本系统还提供给水泵汽轮机汽封系统用汽汽源（详见给水泵汽轮机汽封系统图）。Theglandsteamsystemofthisunitadoptsself-sealingglandsteamsystem,whichistheLPshaftendglandsealingsteamsupplyafterwatersprayattemperationoftheHP,IPcylindershaftendglandsteamleakageduringnormaloperationoftheunit.Thesurplusleak-offsteamoverflowstoLPheaterorcondenserviaoverflowstation.Duringtheunitstart-uporlowloadoperationstage,glandsteamissuppliedbyexternalsteam.Thisglandsteamsystemcancarryoutautomaticswitchingoveraccordingtotheunitglandsteamsupplyrequirementduringoperationoftheunitfromstart-uptofullload.Inaddition,thissystemalsosuppliessteamforBFPTglandsteamsystem(fordetails,refertoBFPTglandsteamsystemdrawing).自密封汽封系统具有简单、安全、可靠、工况适应性好等特点。Theself-sealingglandsteamsystemissimple,safe,reliableandgoodinadaptability.2.系统组成及主要设备2.Systemcompositionandmainequipment该系统由轴端汽封的供汽、漏汽管路，主汽阀和主汽调节阀的阀杆漏汽管路，中压联合汽阀的阀杆漏汽管路以及相关设备组成(详见图0-1-1)。Thissystemiscomposedofsteamsupply,leak-offpipelineoftheshaftendglandsteam,stemleak-offpipelineofthemainstopvalveandthemainsteamcontrolvalve,stemleak-offpipelineoftheIPcombinedinterceptvalveandtherelatedequipment.(Fordetails,see0-1-1).轴封供汽采用三阀系统，即在汽轮机所有运行工况下，供汽压力通过三个调节阀即高压供汽调节阀、辅助汽源供汽调节阀和溢流调节阀来控制，使汽轮机在任何运行工况下均自动保持供汽母管中设定的蒸汽压力。上述三个调节阀及其截止阀和必需的旁路阀组成三个压力控制站，分别为主汽汽源供汽站、辅助汽源供汽站和溢流站。其中辅助汽源供汽站选用了两种汽源供汽，除机组本身的再热冷段外，还增加了本机组以外的辅助蒸汽供汽，机组启动或低负荷运行时辅助蒸汽经辅助汽源供汽站调节阀后，进入自密封系统。此外，为满足低压缸轴封供汽温度要求，在低压轴封供汽母管上设置了一台喷水减温器，通过温度调节站控制其喷水量，从而实现减温后的蒸汽满足低压轴封供汽要求。Theglandsteamsupplysystemadoptsthree-valvesystem,e.g.,underalloperationconditions,theturbinesteamsupplypressureiscontrolledbythreecontrolvalves:HPsteamsupplycontrolvalve,auxiliarysteamsupplycontrolvalveandoverflowcontrolvalve,makingtheturbinemaintainautomaticallyatthesteampressuresetinthesteamsupplymainpipe.Theabove-mentionedthreecontrolvalvesandthestopvalvesandthenecessarybypassvalvesformthreepressurecontrolstations,theyaremainsteamsupplystation,auxiliarysteamsupplystationandoverflowstationrespectively.Theauxiliarysteamsupplystationhasselectedtwosteamsuppliesforsupplyingsteam,inadditiontothereheatcoldsectionoftheunititself,thereisanauxiliarysteamsupplyoutsidethisunit.Duringtheunitstartingorlowloadoperation,theauxiliarysteamenterstheself-sealingsystemviatheauxiliarysteamsupplystationcontrolvalve.Inaddition,tomeetLPcylinderglandsteamsupplytemperaturerequirement,awaterspraydesuperheaterisprovidedontheLPglandsteamsupplymainpipetocontrolthewatersprayamountthroughthetemperaturecontrolstation,sothatthesteamafterattemperationcanmeettheLPglandsteamsupplyrequirement.该系统所有调节阀执行机构均采用气动，由DCS控制。调节阀及执行机构均采用进口件，性能稳定，运行可靠。Actuatorsofallthecontrolvalvesofthissystemshallalladoptpneumatictype,andcontrolledbyDCS.Thecontrolvalveandtheactuatorshallalladopttheimportonesthatarestableinperformanceandreliableinoperation.为保证主汽汽源供汽站、辅助汽源供汽站在机组正常运行过程中始终处于热备用状态，在调节阀前设有带节流孔板的旁路，正常运行时，汽封供汽母管中蒸汽经带节流孔板的旁路进入压力控制站，使之保持热备用状态。Toensurethemainsteamsupplystation,theauxiliarysteamsupplystationisalwaysathotstandbystatusduringtheunitnormaloperation,bypasswithofficeplateisprovidedbeforethecontrolvalve;duringnormaloperation,thesteamintheglandsteamsupplymainpipeentersthepressurecontrolstationviathebypasswithorificeplatetokeepitathotstandbystatus.本系统还设置一台JQ-150型汽封加热器及两台轴封风机(其中一台备用)，用于抽出最后一段轴封腔室漏汽(或气)，并维持该腔室微负压运行。ThissystemisalsoprovidedwithaJQ-150glandsteamheaterandtwoshaftglandfans(oneofthemonstandby),usedforextractingtheglandsteamchambersteamleakage(orair)ofthelastsection,andmaintainthischambertooperateundermicronegativepressure.为了防止杂质进入轴封，各供汽支管上设有Y型蒸汽过滤器。系统供汽母管还设有一只安全阀，安全阀整定压力为0.24MPa(a)，可防止供汽压力过高而危及机组安全。Topreventforeignmattersfromenteringtheglandsteam,Y-steamfilterisprovidedoneachsteamsupplybranch.Thesteamsupplymainpipeofthissystemisalsoprovidedwithasafetyvalve,withthesetpressureof0.24Mpa(a),whichcanpreventtoohighsteamsupplypressurefromendangeringtheunitsafety.3.系统运行3.Systemoperations3.1启动准备3.1Start-uppreparations3.1.1关闭各压力调节站，接通供汽汽源，调节站前供汽管道暖至过热温度。3.1.1Closeeachpressurecontrolstation,connectthesteamsupply,andwarmthesteamsupplypipelinebeforethecontrolstationtooverheattemperature.3.1.2确认系统仪器仪表正常。3.1.2Confirmthesysteminstr