机械密封培训.ppt

西部管道密封培训,JohnCraneTech(Tianjin)Co.,Ltd,培训内容概述,密封基础知识密封系统知识密封的安装要求密封的失效大致判断与客户技术人员进行交流,ConceptsofMechanicalSeals机械密封概念,Shaft,ProcessFluid密封流体,Leakage泄漏,Environment环境,VesselWall釜壁,TheBasicSealingProblem:PreventingLeakage基本的密封问题:防止泄漏,Shaft,ProcessFluid流体流动,Leakage泄漏,Environment环境,VesselWall釜壁,TheConceptofanEndFaceMechanicalSeal机械密封端面的概念,ShaftMovement轴的运动,RequiredFeatures必须的特征,Smallaxialclearance小的轴向间隙Selfadjusting自调节,MatingRing配合环,PrimaryRing补偿环,SecondarySealingElement辅助密封,AFlexibleSealFlexible机械密封,Hydrostaticloading流体静力学负荷Secondarysealingelements辅助密封Replaceableparts可替换的部件,O-RingO型圈,Shaft轴,MatingRing配合环,PrimaryRing补偿环,SnapRing卡环,Anti-XRing挡环,O-RingO型圈,Disk推环,Springs弹簧,Retainer传动套,SetScrew定位螺丝,AnExampleofaCompleteSeal,Simplyput,amechanicalsealis:简单的说,机械密封就是:,1.Awearable,stationary,primarysealingelement一个耐磨,静止的密封件2.Awearable,rotating,primarysealingelement一个耐磨,旋转的密封件3.Asecondarysealingelement二次密封4.Amechanicalloadingdevicetopressprimarysealingelements1and2againstoneanother,and使件1和件2相互贴合的机械装置5.Auxiliarycomponentstocompleteseal辅助密封,Non-flashing没有闪蒸,Flashing闪蒸,Parallel平行,Converging收敛,Diverging发散,FaceSeparation密封面分离,Shape:形态,Gap:间隙,Fluid:流体,TheSealingInterface密封接触面,Lubricant润滑剂,Separation分离面,MagnifiedSurfaceA放大面,MagnifiedSurfaceB放大面,Heat热量,TheSealingInterface密封面,LubricationPurpose:润滑目的Separatesurfaces分离两个面Preventcontactofhighsurfacepoints防止出现面接触Reducefriction/heatgeneration减少摩擦/生热,ProcessFluidActsasLubricantBetweenFaces流体在两个面之间充当润滑剂的过程,Gland密封端盖,PumpHousing泵腔,ProcessFluid工艺流体,InvisibleLeakage:不可见泄漏FluidEvaporatesUponReachingAtmosphere微量的泄漏在大气侧蒸发,PrimaryRing补偿环,MatingRing配合环,Gland密封端盖,PumpHousing泵腔,NoFluidOrDryRunning没有流体或者干运转,PrimaryRing补偿环,MatingRing配合环,WithoutLubrication,FacesRunDryAndOverheat没有润滑干运转导致过热,MatingRing配合环,PrimaryRing补偿环,HeatGeneration生热,Rubbing摩擦ViscousShear粘性剪切力,HeatTransfer热传递,Conduction传导Convection对流,Injection注入,Flushing冷冲洗,RemovesHeat带走热量ReplenishesCoolCleanLubricatingLiquid补充润滑液,PrimarySeal:Flush基本密封:冲洗,SingleSealFlushingBy-PassfromDischarge(APIPlan11)单密封通过出口进行冲洗,By-passLinefromPumpDischargetoSealGland从泵出口到密封端盖的管线,Discharge出口,Flow流动,Suction入口,PrimarySeal:Flush基本密封:冲洗,MinimumPressure.3bar/5psiAboveA?最小压力值要大于A处0.3Bar,Flow流动,Discharge出口,Suction入口,RestrictionalDevice(Bushing)限流装置,SingleSealFlushingfromExternalSource(APIPlan32)单密封通过外部来源进行冲洗,A,PrimarySeal:Quench基本密封:急冷,RestrictionalDevice(Packing)限流装置(盘根),QuenchSource急冷源,ProcessFluid工艺流体,SingleSealQuenchfromExternalSource(APIPlan62)单密封通过外部急冷,APIPipingPlansAPI冲洗方案第二部分,JOHNCRANE,APIPipingPlansAPI冲洗方案,Integral(internal)recirculationfrompumpdischargetoseal内部循环从泵的出口到密封,Advantage优点-Noexternalpiping没有外部冲洗Limitations局限性-Changingflowraterequireddismantlingofpump改变流量需要拆泵-Forcleanpumpagesonly只能是适用干净的介质,APIPipingPlansAPI冲洗方案,PointstoNoteforAPIPlan02:API02冲洗方案应注意的事项：Theinjectiontappingisusedforventingpriortostartup.-在开车前，入口用来进行放空APIplan02isoftenusedtogetherwithplan62,especiallyonhightemperaturebellowsseals.冲洗方案2经常与62一起用，特别是用在高温波纹管密封,APIPipingPlansAPI冲洗方案,Noflushingtothemechanicalseal(dead-ended)机械密封里没有冲洗,PointstoNoteforAPIPlan11:API冲洗方案11应注意的事项-Useanorificetorestricttheflowrateifthedischargepressureis3barhigherthansealchamberpressure.如果出口压力高于密封腔压力3bar，需要用一个孔限制流量-Useoncleanandlowabrasivesduties用在干净，含磨石性颗粒少的工矿,APIPipingPlansAPI冲洗方案,SealFlushingBy-PassfromDischarge单密封通过出口进行冲洗,Recirculationfromsealchamberthroughaflowcontrolorificeandbacktopumpsuction从密封腔里出通过一个孔板返回到泵的入口,PointstoNoteforAPIPlan13:API冲洗方案13应注意的事项-Useanorificetorestricttheflowrateifthesealchamberpressureis3barhigherthansuctionpressure.如果密封腔压力高于入口压力3bar，需要用一个孔板限制流量-handleabrasivesdutybetterthanAPIplan11处理含有磨石性颗粒的工矿13方案号优于11方案-highersealchamberpressuretosuppressvaporisation较高的密封腔压力可抑制它的汽化,APIPipingPlansAPI冲洗方案,+,=,PointstoNoteforAPIPlan14:API冲洗方案14应注意的事项：-Flowbacktosuctionsidewillevacuatevapoursthatmaycollectinsealchamber.-Recommendedforlighthydrocarbonservice.,APIPipingPlansAPI冲洗方案,RecirculationfrompumpdischargethroughaflowcontrolorificeandcoolertosealOpenLoopCoolingCircuit,CoolingWaterOutlet冷水出口,CoolingWaterInlet冷水入口,APIPipingPlansAPI冲洗方案,RecirculationfromapumpingringinthesealchamberthroughcoolerandbacktosealClosedLoopCoolingCircuit冲洗液通过密封腔中的泵效环从密封腔中流出经过换热器，再返回到密封中，形成自封闭循环。形成封闭的冷却回路,Throatbushing,Suction入口,Discharge出口,18-24,Ventathighestpointofthepiping排气在管线的最高点,CoolingWaterOutlet冷水出口,CoolingWaterInlet冷水入口,mechanicalsealwithpumpingring,Heatexchanger换热器,APIPipingPlansAPI冲洗方案,PointstonoteforAPIPlan23:Thermosyphondesign热虹吸设计*heatexchanger换热器18to24“abovepumpcentreline.在泵中心线以上18to24*Preventoverheatinginstandbyandstartup.*在泵启动和备用时，要防止过热。Installclosefittingneckbushingatthebottomofsealchambertoisolatetheheatfromtheimpellerend.在密封腔底部安装喉部衬套用来隔离从叶轮传出的热量Usedonhightemperatureapplicationstominimiseheatloadonthecoolerbycoolingonlysmallamountofliquidthatisrecirculated.用于高温工况，通过冷却密封腔的小部分的循环流体来使冷却器的热负荷降至最低.Forhightemperatureboilerfeedpumpapplications用于高温锅炉给水泵上Otherapplications其他应用*hightemperatureliquidclosetobubblepoint.*接近沸点的高温液体.,APIPipingPlansAPI冲洗方案,Recirculationfrompumpdischargethroughacycloneseparatordeliveringcleanfluidtothesealandfluidwithsolidsbacktopumpsuctionline冲洗液从泵出口流出，通过一旋液分离器，使干净流体进入密封腔，带有颗粒的流体返回到泵入口处形成封闭循环,APIPipingPlansAPI冲洗方案,PointstoNoteforAPIPlan32:对于APIplan32须注意:-Choseapropersourceofsealflushtoeliminatethepotentialforvaporisationoftheinjectedfluidandtoavoidcontaminationofthefluidbeingpumpedwiththeinjectedflush.选择合适的密封冲洗源，以减少冲洗流体的汽化，同时可避免冲洗流体被污染。-Installalabyrinthbushingatthebottomofthestuffingboxtocontroltheflushingandpressureifnecessary.-如有必要的话，在密封腔底部安装喉部衬套或迷宫密封来控制冲洗和压力。,APIPipingPlansAPI冲洗方案,SingleSealFlushingfromExternalSource单密封通过外部来源进行冲洗,ThroatBushing,Recirculationfrompumpdischargethroughacycloneseparatordeliveringcleanfluidthroughacoolerandthentosealandfluidwithsolidsbacktopumpsuctionline,CoolingWaterOutlet,CoolingWaterInlet,APIPipingPlansAPI冲洗方案,Needlevalve,Externalreservoirprovidingadead-endedblanketoffluidtothequenchconnectionofthegland.,PointstoNoteforAPIPlan51:对于APIplan51须注意:-Deadendedblanketonatmosphericsideofsealtopreventfreezingofmoisture.Sealfacewillnotsticktogetherwhenthepumpstarted.-在密封大气侧，一端封闭的情况可防止潮气的冻结，这样在泵启动时，密封面就不会粘接在一起。Typicalapplication:典型的应用Pumpoperatingbelow0C应用于泵在0C以下-API6108thEditionhaseliminatedthispipingplan.API610第八版已经取消这个冲洗方案-,APIPipingPlansAPI冲洗方案,PipingSystems,APIPipingPlansAPI冲洗方案,Afluidusedasalubricantorbufferbetweendualmechanicalseals.这种液体象缓冲剂，润滑剂用在双机械密封Thebufferfluidisalwaysatapressurelowerthanthepumpprocesspressurebeingsealed.缓冲液的压力通常低于被密封的介质的压力,Afluidwhichisintroducedbetweendualmechanicalsealstocompletelyisolatethepumpprocessliquidfromtheenvironment.双机械密封里的隔离液用于是泵的工艺液体与大气分离Pressureofthebarrierfluidisalwayshigherthanthepumpprocesspressurebeingsealed.隔离液压力总是高于泵的运作压力,Thepurposeoffluidcirculationistoremoveheatfrommechanicalseal,APIPipingPlansAPI冲洗方案,Onapplicationsbelowambienttemperature,circulationofbarrierfluidmaynotbedesirable.这种情况适用于比室温低的工况，隔离液的循环不能满足要求。Theatmospherewillheatthereservoirandconsequentlyaddheattothesealarea.外部对储罐进行加热，从而，对密封区域进行加热。,Fluidcirculationbytemperaturedifferencebetweenthesealandreservoir.流体依靠密封腔和储罐的温差进行循环Highertemperatureliquidatsealhaslowerdensityrisestothereservoir.密封中的高温流体密度较小，依靠热虹吸现象上升到储罐中Lowertemperatureliquidatreservoirhashigherdensityfallstothesealtoprovidecooling.储罐中的低温流体密度较大，下降到密封腔中对密封进行冷却,ExternalForceCirculation,Thermosyphon,PumpingRing,DeadEnded,APIPipingPlansAPI冲洗方案,PointstoNoteforAPIPlan52:TypicallyusedwithanArrangement2unpressuriseddualseal.通常用于不带压双封Duringnormaloperation,circulationismaintainedbyaninternalpumpingring.在正常操作情况下，通过腔内的泵效环维持循环Thereservoirisusuallycontinuouslyventedtoavapourrecoverysystemandismaintainedatapressurelessthanthepressureinthesealchamber.储罐通常与回收系统相连通，罐内压力通常低于密封腔压力,PressureGauge压力计,LevelGauge水准仪,Fillvalve,Orifice,Drain,LevelSwitch(H)电平开关,LevelSwitch(L),PressureSwitch压力开关,(NormallyOpen),Ventvalve排气阀,Externalreservoirprovidingbufferfluidfortheoutersealofanunpressuriseddualsealarrangement.外部储罐对不带压双封的外密封起缓冲液的作用,APIPipingPlansAPI冲洗方案,PressureGauge压力表,LevelGauge水准仪,LevelSwitch(L)电平开关,VentValve排气阀(NormallyClose)通常关着,Orifice,PressureSwitch压力操纵开关,ExternalPressure外部压力Source,One-wayBlockValve(NormallyOpen),PointstoNoteforAPIPlan53:TypicallyusedwithanArrangement3pressuriseddualseal.通常用于带压双封Duringnormaloperation,circulationismaintainedbyaninternalpumpingring.在正常操作情况下，通过腔内的泵效环维持循环Thereservoirpressureisgreaterthantheprocesspressurebeingsealed.罐内压力通常高于被密封介质压力,Externalreservoirprovidingpressurisedbarrierfluidfortheoutersealofanpressuriseddualsealarrangement.外部储罐对带压双封的外密封起隔离液的效果,Drain,APIPipingPlansAPI冲洗方案,PointstoNoteforAPIPlan54:TypicallyusedwithanArrangement3pressuriseddualseal.通常用于带压双封Duringnormaloperation,circulationismaintainedbyanexternalpumporpressuresystem.在正常操作情况下，通过外部的泵或压力系统维持循环Thecirculatingbarrierfluidpressureisgreaterthantheprocesspressurebeingsealed.循环隔离液的压力高于被密封介质的压力,Externalbarrierfluidsystemprovidingpressurisedbarrierfluidfortheoutersealofanpressuriseddualsealarrangement外部隔离液系统对带压双封的外密封提供带压隔离液,APIPipingPlansAPI冲洗方案,Safetouse,handle,store储藏、操作、使用安全可靠Stableliquidatambienttemperatures在室温下，性能稳定NotaVOC,VHAPorotherregulatedcompound不易挥发、非有毒物质Nonflammable不易燃烧Nonfoamingwhenpressurised高于常压时，不易起泡Cleanandgoodlubricity干净且有较好的润滑性Compatiblewithprocessfluid与工艺流体有互容性Compatiblewithsealmaterials与密封材料相一致Goodheattransferproperties有好的传热性能Goodflowqualitiesatverylowtemperatures在低温下，有好的流动性Lowsolubilityofgas对气体有较低的溶解性Localavailability当地容易获得Lowcost成本低,VOC:VolatileOrganicCompoundVHAP:VolatileHazardousAirPolutants,SelectionofBuffer/BarrierFluid,APIPipingPlansAPI冲洗方案,Tappedconnectionsforthepurchasersuse在接口处攻螺纹，以方便用户使用,PointtoNoteforAPIPlan61:对于APIplan61须注意:Typicallythisplanisusedwhenthepurchaseristoprovidefluid(suchassteam,gas,orwater)toanauxiliarysealingdevice.通常在买方能给密封辅助系统提供流体（如蒸汽、气体或水）的情况下，才采用该方案,APIPipingPlansAPI冲洗方案,PointstoNoteforAPIPlan62:对于APIplan62须注意:Thequenchmayberequiredtopreventsolidsfromaccumulatingontheatmosphericsideoftheseal.增加吹扫口以防止在密封大气侧有颗粒的积累Typicallyusedwithaclose-clearancethrottlebushing.普遍使用节流衬套,APIPipingPlansAPI冲洗方案,SingleSealQuenchfromExternalSource单密封通过外部急冷,API6822ndEditionAPI682第二版NewPipingPlans新的冲洗方案,Plan14(Plan11+13)冲洗方案14Plan53s-Arrangement3,ContactingWet(CW)Seals53方案-排列方案3，接触式湿密封53atraditionalconfiguration传统构造53bbladderaccumulator蓄能器53cpistonpot/accumulator活塞/蓄能器ContainmentSeal二次辅助密封Plan72Arrangement2w/ContainmentSeal(CS)Plan75Arrangement2w/ContainmentSeal(CS)Plan76Arrangement2w/ContainmentSeal(CS)GasBarrierSeals气体Plan74Arrangement3,Non-Contacting(NC)Seals排列方式3，非接触式密封,Plan53a(A.4.12),Arrangement3,ContactingWet(CW)Seals排列方式3，接触式湿密封DualPressurised(Double)Seals带压双封Utilisesdirectnitrogenblanketforpressure利用氮气层来增压duetonitrogenentrainmentinthebarrierliquidAPI682limitsthemaximumnitrogenpressureto10barg,JCrecommendationismaximumnitrogenpressure21barg,aslongasthebarrierfluidtemperatureislessthan120CAPI682限制了氮气的最大压力为10barg,约翰克兰建议只要隔离液温度小于120度，最大氮气压力21barg,API6822ndEditionAPI682第二版NewPipingPlans新的冲洗方案,Plan53b(A.4.12),Arrangement3,ContactingWet(CW)Seals排列方式3，接触式湿密封DualPressurised(Double)Seals带压双封Utilizesbladderaccumulatorforpressure利用蓄能器来增压Bladdereliminatesnitrogencontactwithbarrierliquid蓄能器把氮气与隔离液分开Allowsforhigherpressureapplications允许高压力应用,ConfigurationIncludes:Accumulator蓄电池PressureIndicator压力显示器PressureSwitch压力开关HeatExchanger换热器,API6822ndEditionAPI682第二版NewPipingPlans新的冲洗方案,Plan53c(A.4.12),Arrangement3,ContactingWet(CW)Seals排列方式3，接触式湿密封DualPressurised(Double)Seals带压双封Utilizespistonpotforpressure利用活塞增压,API6822ndEditionAPI682第二版NewPipingPlans新的冲洗方案,Plan53c(A.4.12),Allowsforhigherpressureapplications允许高压力应用Configurationincludes:构造包括Pistonpot活塞Pressureindicator压力显示器Pressureswitch压力开关Heatexchanger换热器Levelswitch电平开关,Pistonpoteliminatesnitrogencontactwithbarrierliquid活塞缸阻断了隔离液与氮气的连接Pistonprovidesconstantpressureratiotoseals(1.1:1)活塞给密封提供持续的压力比率,Spring弹簧,API6822ndEditionAPI682第二版NewPipingPlans新的冲洗方案,BarrierFluidTemperature(7.3.4.1.1)隔离流体温度,Liquidbarriersystemsshallbedesignedsuchthatthatmaximumtemperaturedifferentialbetweenthebarrierfluidinletandoutletimmediatelyadjacenttothesealchamberis:设计隔离液系统允许的温差不一样，入口和出口温差不一样8degreeCforglycol/waterordieselbarrierfluids;and对于水，乙二醇，柴油隔离液，允许最大温差8度16degreeCformineraloilbarrierfluid矿物油隔离液允许最大温差16度,Plan11withPlan53,Arrangement3mayusePlan11&53排列方式3可以用11&53方案Improvedheattransfer增加换热Reversepressurecapability压力转换能力“BacktoBack”sealsusesPlan53背对背密封用53方案,API6822ndEditionAPI682第二版NewPipingPlans新的冲洗方案,Plan72(A.4.16),Arrangement2,w/ContainmentSeal(CS)排列方式2，辅助二次密封DualUn-Pressurised(Tandem)Seals不带压双封Dry-runningsecondarycontainmentseal干运转二次辅助密封Lowpressurenitrogensweep(purge)低压氮气吹扫Sweepsprimaryleakagetocollectionsystem主密封泄漏的东西排放到收集系统里Dilutesprimaryleakagetoloweremissionlevels稀释泄漏的东西UsedinconjunctionwithPlan75or76，与75方案获76方案一起使用,CSV:containmentsealventCSD:containmentsealDrainGBI:gasbufferinletFIL:coalescingfilter,API6822ndEditionAPI682第二版NewPipingPlans新的冲洗方案,Plan74(A.4.17),Arrangement3,Non-contactingSeals(NC)排列方式3，非接触式密封DualPressurised(Double)GasBarrierSeals带压Nitrogengasbarrier氮气隔离1.75-2bar(25-30psi)abovesealchamberpressure密封腔压力1.75-2barZeroemissions零泄漏EssentiallyaT2800panel2800类型控制面板,GBI:gasbufferinletGBO:gasbufferoutlet(NC)(usedonlytodepressurize),API6822ndEditionAPI682第二版NewPipingPlans新的冲洗方案,Plan75(A.4.18),Arrangement2,w/ContainmentSeal(CS)排列方案2，二次辅助密封DualUn-Pressurised(Tandem)Seals双无压密封Dry-runningsecondary辅助密封干运转Condensatecollectionreservoir(8.6.5.2)冷凝液收集罐Usedwhenprimarysealleakagemaycondense(doesnotcompletelyvaporize)用于从主密封泄漏出来的可冷凝的工况MaybeusedinconjunctionwithPlan72或许和72方案一起使用,API6822ndEditionAPI682第二版NewPipingPlans新的冲洗方案,Plan76(A.4.19),Arrangement2,w/ContainmentSeal(CS)排列方式2，二次辅助密封DualUn-PressurisedSeals(Dry-runningsecondary)双无压密封PrimaryleakageroutedtoflareorventUsedwhenprimarysealleakagewillnotcondense(completelyvaporizes)用于从主密封泄漏出的不可冷凝的工况Essentiallya48SCor28LDpanelleakagedetectionMaybeusedinconjunctionwithPlan72或许和72方案一起