密封油系统概述

发电机密封油系统概述Feb.20061氢气的密封密封油的作用:为了保证将一定压力的氢气密封于发电机机壳内,不从动静间隙间溢出.密封油系统应用一切相关设备,使供油压力高于氢压0.5bar,保证了氢气的密封.密封油系统的可靠性对机组运行的可靠性是非常关键的.密封油系统必须保证在机组静态(0rpm)和带负荷运行(3000rpm)时,都保证密封功能.2

单流环密封油系统

3三流环密封油系统三流环系统

保证了在氢压较高时仍然有很低的漏氢量.实际的密封元件为套于轴上的密封环(氢侧和空侧),与轴颈间的间隙非常小,并沿轴向由密封瓦座定位和固定.密封环沿圆周有三个油槽.每个密封油槽在环的的侧面沿圆周都钻有很多油孔,密封油则在一定的设计油压下,从油孔注入,并填充到密封环和大轴间的间隙中去,起到密封的作用.4

三流环密封油系统

1.真空油2.含空气的油3.饱含氢气的油4.空气中带有氢气(微量)5密封环在瓦座内的情况空侧排油腔室氢侧排油腔室空侧油真空油氢侧油氢气侧空气侧虽然油源一致,但是经过不同管路和设备,形成空侧、真空侧、氢侧油，注入到三个油槽中6三流环密封油系统三个不同的油路：-空侧油,含空气,以高于氢压0.5bar的压力从空侧密封环的中间油槽注入。真空油,去处气体,

以高于空侧油大约0.3bar的压力从空侧密封环和氢侧密封环中间形成的油槽注入。-氢侧油,饱含氢气,

以和真空油相同的压力从氢侧密封环中间的油槽注入。7密封油压力空侧油入真空油入氢侧油入真空油从空侧油回油流回,保证了空气不进入发电机内部,进而保证了氢气的纯度.空侧和真空油,回油在一起

氢侧回油

真空油空侧油氢侧油发电机外发电机内氢压8密封油装置集成式装置,一般位于0m汽机房发电机下,主油箱(空侧油箱)安装于装置侧.装置与发电机靠油管路相连.空侧油箱真空油箱9密封油装置真空油泵空侧油泵氢侧油泵密封油差压控制阀真空油箱10密封油装置空侧油箱泄油观察窗真空油箱冷油器11Air-OilCircuit-1Intheair-oilcircuitoilispumpedintothegrooveontheatmosphericsideoftheshaftsealingring.Thesupplypressureattheringis0.5barabovethehydrogenpressureinthegenerator.Thiscircuitprovidesthesealingfunction,i.e.itservestocontaintheinternalhydrogenpressureattheseal.Inviewoftheimportanceofmaintainingpumpingpowerinthiscircuit,themaina.c.motordrivenpump(1)isbacked-upbyaseconda.c.andad.c.motordrivenpump.Thecooler(2)andthefilter(3)haveboth100%redundancy.Theair-oiltank(4)providesthereservoirfortheair-oilcircuit.Oilisdrawnfromthistankbytheserviceair-oilpumpandpumpedtothethesealoilunitandthentotheair-sideDEandNDEsealingringsviatheair-oilcoolerandfilter.12Air-OilCircuit–2Inordertoensurepropergeneratorsealing,thesealoilpressuremustbemaintained0.5barabovetheH2pressureatalltimesandinalltypesofoperation.Thistaskisperformedbythedifferentialpressurecontroller(11),whichleadstheoilsurplusbacktotheair-oiltank(4).Sincethevacuum-oilpressureisset0.3barhigherthantheair-oilpressure,theair-oilflowsintotheun-pressurisedair-sidedrainchambersandfromtherebacktotheair-oiltank.Theoilvapourinair-oiltankisexpelledbytheexhaustblower(fan)(9).Atthesametime,thisfanensuresthatthenecessarypartialvacuumispresentinthesealingringhousing.13差压控制阀氢压(4bar)(氢侧排油腔室压力)空侧油压(4,5bar)型号42.25油流向见图中箭头所示.阀芯(3)的位置影响了阀座(2)前后的油压差.阀位靠弹簧(14)调整平衡,压力取样脉冲管接至阀位控制室来根据氢压及空侧油压调整阀门开度,进而控制差压.差压控制阀对轻微的差压变化不起作用.14Vacuum-OilCircuitTheoilrequiredfordegasificationistakenfromtheair-oillinedownstreamofthefilterandtakentothevacuumtank(7)viathelevelcontrolvalve.Allentrainedgasesareseparatedoutoftheoilbythevacuumpump(10)onthe

vacuumtank.Theoptimumvacuum-oilpressurecanbeadjustedbythevacuumpressureregulator(12).TheevacuatedoilispumpedbetweenthetwoDEandNDEair-sideandgassidesealingrings(middlegroove)bythevacuumoilpump(8).Theoilpressureinthevacuumoilcircuitissetatthepressureregulationsvalve(12)andsothatvacuum-oilpressureisalways0.3barhigherthantheair-oilpressure.AstheH2pressureisregulatedtothesamevalue,thevacuum-oilflowsacrossthepressuredroptotheair-oilandreturnstotheair-oiltank15氢侧油路汽侧和励侧的氢侧密封油路各自独立.TheH2-oilpumps(5)supplythehydrogen-saturatedoiltotheDEandNDEgas-sidesealingringsviatheH2-oilcoolers(6).Theoillevelatthepumpinletsismaintainedconstantbythetwooilcolumncontrollers(e),whichensuresthattheH2-oilpressureisalwaysadjustedtothevacuum-oilpressureattheshaft.Duetothepressuredroptothegassideofthegenerator,theH2-oilflowsintothegas-sidedrainchambersandbacktotheH2-oilpumps.Withtheexceptionofcontrolprocesses,thiscircuitcanthereforeberegardedasaclosedoilcircuit.16氢侧油路氢侧密封油压由氢侧油泵入口侧的液位静压,经压力调节阀(13)来保证.这样回油进入氢侧泄油腔室,而经回油管路回到氢侧油泵.如果氢侧油或真空油故障,则从真空或空侧补充来的油也经氢側泄油腔室排至回油管,并从泄油阀(1