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喀北电站汽机资料GLANDSEALSYSTEM喀北电站汽机资料在汽轮机转子穿过外缸的部位，必须采取措施用以防止外部空气漏入汽缸，从而影响排汽缸的真空，同时也必须防止汽缸内蒸汽漏出汽缸，漏入前轴承箱容易造成油中带水，漏至汽机房破坏汽机房环境。汽轮机的汽封系统就是为了完成这一功能而设置的。Measuresmustbetakenattheportionswheretheturbinerotorpassesthroughtheoutercasingtopreventtheairleakagefromoutsideintothecasingandaffectthevacuityoftheexhausthood.Inthemeantime,thesteaminsidethecasingmustalsobepreventedfromitsleakagetotheoutside,especially,tothefrontbearingboxtoleadtoamixingofthelubricationoilwithwaterandtotheturbinehousetodeteriorateitsenvironmentalconditions.Theglandsealsystemofasteamturbineisfurnishedjustforsuchapurpose.喀北电站汽机资料辅助蒸汽母管Steamsealcooler喀北电站汽机资料Steamsealcooler喀北电站汽机资料Steamsealcooler汽封系统图喀北电站汽机资料本系统是高低压分开供汽的汽封系统.ThepresentsystemisaglandsealsystemcapableofsupplyingsteamtoHPandLPcylinderseparatelydeveloped.喀北电站汽机资料系统中主要设备有：高压轴封供汽调节站、低压轴封供汽调节站、高压喷水减温调节站、低压喷水减温调节站、各种截止阀、疏水阀等，连同汽封冷却器、疏水扩容器等设备，共同构成了该机组汽封系统。该系统能够维持汽封供汽母管的压力在0.107～0.11MPa(A)之间，供汽温度在121～150℃之间，控制部分可根据实际情况接入控制室，通过DCS系统调节各执行机构动作。Thesystemmainlyincludesthefollowingmainequipmentitems:HPglandsealsteamsupplyregulatingstation,LPglandsealsteamsupplyregulatingstation,HPwaterspraydesuperheatingregulatingstation,LPwaterspraydesuperheatingregulatingstation,variouscut-offvalvesanddrainvalves,glandsealcoolersanddrainflasktanksetc.Itcanexerciseafunctionofmaintainingthesteampressureinsidetheglandsealsteamsupplymainlinebetween0.107Mpaand0.11Mpa,thesteamtemperaturebetween121℃and150℃.ThecontrolsignalscanbesenttothecontrolroomaccordingtothespecificcasesandthencontroltheactionofvariousactuatorsthroughtheDCSsystem.喀北电站汽机资料转子汽封GlandSealofRotor在汽缸两端装有汽封体和汽封圈，汽封圈上汽封齿环绕转子，表面仅留有为防止在运行过程中发生接触的间隙。Glandcasingsandsealingringsareequippedatbothendsofthecylinderandtheteethonthesealringssurroundtherotorwithaclearancebeingkepttopreventanycontactbetweenthesaidteethandtherotorsurfaceduringtheturbineinoperation.在汽轮机启动时，凝汽器抽真空，汽缸内的压力低于大气压力，供至“A”腔室的汽封蒸汽在一侧通过汽封漏入汽轮机汽缸内，在另一侧漏入“B”腔室，汽封抽汽器正常运行，使“B”腔室维持压力稍低于大气压力，因而空气通过端汽封漏入“B”腔室，形成汽气混合物，通过一个与汽封抽汽器相连的接口，从“B”腔室被抽出。(见图1)Duringstartupofthesteamturbine,thecondenserisevacuatedandthepressureinthecylindersislowerthantheatmosphericpressure.Thesteamsuppliedtothe“A”chamberoftheglandsealisleakedtothecylinderoftheturbineatonesideandto“B”chamberatanotherside.Iftheairejectorfortheglandsealsisinnormaloperationtomaintainthepressurein“B”chamberslightlylowerthantheatmosphericpressure,theairisleakedintothe“B”chamberthroughtheglandsealattheend,formingasteamandairmixture.Thenthemixtureisevacuatedfrom“B”chamberviaaportconnectedwiththeairejectorfortheglandseals(seeFig.1).喀北电站汽机资料喀北电站汽机资料随着机组负荷的不断提高，高中压缸两端的压力逐渐增加，但因“C”腔室与2号低压加热器(JD2)相连，所以高中压汽封的“A”腔室始终保持送汽状态；由于低压缸压力仍保持一定的真空状态，所以低压汽封的“A”腔室始终保持送汽状态。当除氧器能供汽时，则切到正常运行系统，即由除氧器来供汽(见图2)。Withacontinuousincreaseoftheloadofthesteamturbine,thepressuresatbothendsofHPandIPcylinderwillgraduallyincrease.Asthe“C”chamberisconnectedtothe2#LPheater(JD2),sothe“A”chambersinHPandIPcylinderisalwayskeptinasteam-supplyingstate.DuetotheLPcylinderbeingmaintainedatavacuumstate,the“A”chamberofLPglandsealsisalwayskeptinasteam-supplyingstate.Whenthedeaeratorhasanabilitytosupplysteam,thenormaloperationsystemshallbeputintoservice,i.e.supplyingsteambythedeaerator(seeFig.2).喀北电站汽机资料喀北电站汽机资料蒸汽压力温度控制装置SteamPressureandTempController在汽轮机启动和低负荷运行状态下（一般低于40%负荷），辅助汽源经过轴封压力调节阀减压及喷水减温调节阀控制的减温器减温后，向汽封母管供蒸汽。随着负荷不断提高(约40%负荷左右)，当除氧器的汽平衡室压力建立起来时，则切换到正常运行系统，即由除氧器来供汽。供汽母管配有热电偶及压力变送器(设计院选配)，母管的温度和压力变化是通过与其相连的热电偶和压力变送器传递的，信号传到主控制室，由主控制室DCS系统完成对调节阀的温度和压力控制。Undertheconditionofthesteamturbineoperatinginthestartupstateandatalowload(generallylowerthan40%oftheratedload),theauxiliarysteamsourceshallsupplysteamtotheglandsealsteammainlineafterthesteampressurehasbeenreducedbytheglandsealsteampressureregulatingvalveandthesteamtemperaturehasbeendesuperheatedbyanattemperatorcontrolledbythewaterspraydesuperheatingregulatingvalve.Withacontinuousincreaseoftheload(toabout40%oftheratedload),whenasteampressureisestablishedinthesteamequilibriumchamberofthedeaerator,thenormaloperationsystemshallbeputintooperation,i.e.thesteamtotheglandsealsshallbesuppliedbythedeaerator.Thesteamsupplymainlineshallbeequippedwiththermocouplesandpressuretransmitters(selectedbyanelectric-powerdesigninginstitute).ThesignalsshowingthechangeofsteamtemperatureandpressureinthemainlinearetransmittedbythethermocouplesandpressuretransmitterstothemaincontrolroomandthentheDCScontrolsystemshallexerciseacontroloverthesteamtemperatureandpressurebyuseoftheregulatingvalvebasedonthesignals.喀北电站汽机资料汽封压力调节阀能在所有运行条件下以其DCS系统的给定压力向各汽封供汽。轴封送汽调节阀压力给定值为0.107～0.11MPa（A）。（因母管压损未知可按实际情况调整）TheglandsealsteampressureregulatingvalveshallsupplysteamtovariousglandsealsatapressuresetbytheDCScontrolsystematalltheoperatingconditions.Theglandsealsteampressuresetpointbytheregulatingvalverangesfrom0.107～0.11MPa（A）(duetothepressurelossinthemainlinebeingunknown,onecanmakeanadjustmentaccordingtothespecificcase).喀北电站汽机资料供汽母管蒸汽温度主要是由减温器来控制的，减温水来自于凝结水泵，减温水量是由减温水调节阀来控制的，温度信号取自供汽母管的温度，将温度信号转换为4～20mA电信号送到主控制室，由DCS系统来控制减温水调节阀的执行机构，使供汽母管蒸汽温度控制在121～150℃之间。Thesteamtemperaturein