《机械密封基础知识》PPT课件讲义

（Suitableforteachingcoursewareandreports）机械密封基础知识主要内容机械密封的典型结构、组成部分机械密封的布置方式密封腔机械密封离心泵－结构rotatingsealunittwoflatslidingsurfaces,whichmaintainacloserunningclearancewhileseparatedbyafluidfilmstationarysealunit什么是机械密封？Whatisamechanicalseal?机械密封的结构机械密封的基本组成Looseringsetscrewedtotheshaft动环靠紧钉螺钉传动与轴一起旋转1机械密封的基本组成O-ringpreventsleakagethroughtheboreO型圈防止通过间隙泄漏Wearherewillcreateleakage端面磨损会产生泄漏2机械密封的基本组成Springensuresautomaticadjustment弹簧确保动环能够自动补偿HeatgeneratedhereLeakpathLargecomponent3机械密封的基本组成Recirculationforcooling冷却循环GasketorO-ring垫片或O型圈PrimarySeal主密封SecondarySeal二次密封TertiarySeal三次密封4机械密封的基本组成SeatorMatingRing静环或非补偿环FaceorPrimaryRing动环或补偿环SpringorSpringForce弹簧5机械密封的基本组成O-RingO型圈Shaft轴MatingRing非补偿环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定位螺丝机械密封的基本组成：小结机械密封由以下部分组成：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辅助密封机械密封的结构—主密封主密封PrimarySealSPRINGFORCEFLUIDPRESSUREfluidfilm(3-5microns)athinfilmofliquidformstheprimary(dynamic)sealbetweentherotatingandstationaryelementsFILMREACTION主密封PrimarySealSeatorMatingRingFaceorPrimaryRingSprings-Higherpressureonoutsidediameter-Higherpressureholdsfacesclosed-Fluidisforcedbetweenfacestolubricate-SpringskeepfacesclosedwhennopressureFaceslappedflattowithin1-3lightbands.密封面研磨后平面度1-3个光带主密封－膜厚度PrimarySeal–FilmThickness主密封－膜厚度PrimarySeal–FilmThicknessFluidfilmthicknessisveryimportant膜厚很重要toothin-wear,causingearlysealfailure太薄—磨损，早期失效toothick-visibleleakage太厚—泄漏量大Mustbe:必须：present-bewaredryrunning存在—避免干运转stable稳定clean-bewareabrasivewearsymptoms干净—避免磨粒磨损reasonableviscosity合理的黏度temperaturecontrolled控制温度acceptablepressure压力可以接受主密封－膜厚度PrimarySeal–FilmThicknessLubricant润滑剂Separation分离面MagnifiedSurfaceA放大面MagnifiedSurfaceB放大面Heat热量密封面TheSealingInterfaceLubricationPurpose:润滑目的Separatesurfaces分离两个面Preventcontactofhighsurfacepoints防止出现面接触Reducefriction/heatgeneration减少摩擦/生热流体在两个面之间充当润滑剂的过程ProcessFluidActsasLubricantBetweenFacesGland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非补偿环主密封－平面PrimarySeal–FaceFlatnessIffacesnotflat,contactgeneratesheatExcessivewear-shortlife如果密封面不平，摩擦生热，过度磨损，寿命短1lightband=0.0003mm1光带=0.0003mmGland密封端盖PumpHousing泵腔NoFluidOrDryRunning没有流体或者干运转PrimaryRing补偿环MatingRing非补偿环没有润滑干运转导致过热WithoutLubrication,FacesRunDryAndOverheat稳定液膜StableFluidFilm主密封－ 总结 初级经济法重点总结下载党员个人总结TXt高中句型全总结.doc高中句型全总结.doc理论力学知识点总结pdf Amechanicalsealisself-adjustingforwearHasthreemainparts:-PrimaryRing(narrowerrunningface)MatingRing(widerrunningface-harder)SpringForceUsuallythematingringisstationary&theprimaryringrotateswiththeshaftTheliquidfilmbetweentheprimaryring&matingringisonly0.5-3.0micronsthickTherearethreemainsealingareas:-PrimarySeal-PrimaryRing&MatingRingSecondarySeal-PrimaryRing&ShaftTertiarySeal-MatingRing&Housing机械密封的结构—二次密封二次密封SecondarySeal二次密封SecondarySealThreebasicformso-ringswedgesbellowselastomermetalformed冲压成型edgewelded焊接PTFETwogroupsPusher推进式slidingo-ringsWedges楔形环Non-pusher非推进式bellowsTeflonBellows聚四氟乙烯波纹管ElastomericBellows橡胶波纹管HalfConvolution半波WeldedMetalBellows焊接金属波纹管VRingsV型圈UCup杯型Wedge楔形EncapsulatedORing包覆O型圈ORingO型圈二次密封元件SecondarySealingElementsPusher推进式Non-Pusher非推进式O-ringsecondarysealmustslidealongshaftassealfacewearsO型圈二次密封在密封面磨损的时候必须能够沿轴滑动Bellowssecondarysealexpandstoaccommodatefacewear.Bellowstailisstationaryagainstshaft.波纹管伸长能够补偿密封面磨损,波纹管尾部与轴保持静止vs.推进式/非推进式Pushervs.Non-Pusher二次密封：推进式SecondarySeal:PusherAsthefacemovesforwardtotakeupwear,theo-ringmovesforwardwiththeface,pushedbythehydraulicandspringpressures二次密封：推进式SecondarySeal:PusherPositivedriveCompactmultiplespringsOptimisedfacedesignTypicalpusherseal-lowemissionduties典型的推进式密封Optimisedcoolingflow二次密封：推进式SecondarySeal:PusherAdvantagessuddenfailureveryunlikelyhigherpressurecapability-facenotstressedwidechoiceofmaterialsforallcomponentsfieldrepairableDisadvantageshang-up(notlikelywhereo-ringiswellisolated)permanentset/pressureproblems(causehang-up)excellentshaftsurfacefinishrequiredmaximumtemperature~+260°C推进式密封：卡滞PusherSeal:Hang-upProductleakagesolidifies/crystallises/polymerisesPreventso-ringpushingforward-leakageincreases泄漏的介质凝固/结晶/聚合阻止O型圈移动，造成泄漏增加Anexternalquenchwillpreventhang-up外部冲洗可以避免卡滞二次密封：O型圈SecondarySeal:O-Ring二次密封：楔形环SecondarySeal:Wedge二次密封：非推进式SecondarySeal:Non-PusherBellowsflexestotakeupwear,misalignmentandaxialplay波纹管伸缩弯曲，补偿磨损，不对中和轴向跳动FinemachinedshaftsurfacerequiredDonotusea‘good’lubricant-neverusesilicongrease对轴表面光洁度 要求 对教师党员的评价套管和固井爆破片与爆破装置仓库管理基本要求三甲医院都需要复审吗 高，不能使用润滑剂二次密封：波纹管SecondarySeal:BellowsElastomerBellowsgripsshafttightlyNocontacthere二次密封：金属波纹管SecondarySeal:MetalBellowsstatico-ring静止O型圈Type10TType10R二次密封：PTFE波纹管SecondarySeal:PTFEBellows机械密封的结构—三次密封三次密封TertiarySeal三次密封TertiarySealPreventsleakageroundmatingring防止通过非补偿环周围泄漏Sometimesalsopreventsmatingringrotation有时还起防转的作用三次密封TertiarySealFourbasictypes4种基本形式O-ringselastomersSeatRings(squareorrectangularsection)PTFEgraphiteCupRingselastomersGasketsorFlatJointsPTFEcompressedfibre三次密封：O型圈TertiarySeal:O-ring三次密封：O型圈TertiarySeal:O-ring三次密封：O型圈TertiarySeal:O-ring三次密封：方形环TertiarySeal:SeatRing三次密封：杯形环TertiarySeal:CupRubber三次密封：垫片TertiarySeal:Gasket三次密封：垫片TertiarySeal:Gasket三次密封：端盖TertiarySeal:Cover/GlandPlate机械密封的结构—弹簧设计特点DesignFeaturesSprings弹簧ProvideTheInitialClosingForce提供初始闭合力AreVeryImportantAtLowPressures低压下很重要AreNotSoImportantAtHighPressures高压下不重要设计特点DesignFeaturesSprings弹簧Single单弹簧Multiple多弹簧Bellows波纹管Wave波形设计特点DesignFeaturesSprings弹簧HighSpeedSealsUseStationarySprings(5000ft/minTypicalBreakPoint)高速机械密封使用静止弹簧(5000ft/min典型的分界点)机械密封的结构—传动机构DriveMechanism驱动机构MustTransmitTorque必须能够传递转距MustAllowAxialMovement(PrimaryRing)必须能够使动环轴向运动驱动机构的类型TypesofDriveMechanismsPinDrive销驱动DentDrive凹轮驱动SlotandEar缝和支耳SpringDrive弹簧驱动SetScrewDrive定位螺丝驱动SnapRingDrive卡环驱动ElastomerDrive橡胶驱动KeyDrive键驱动驱动机构的类型TypesofDriveMechanisms机械密封的主要材料主密封材料PrimarySealMaterialsFace(PrimaryRing-Narrow)MaterialsCarbon-graphite碳石墨resinimpregnated浸树脂antimonyimpregnated浸锑CarbonconvertedtoSiliconCarbideresinimpregnated主密封材料PrimarySealMaterialsCarbonconvertedtoSiliconCarbide主密封材料PrimarySealMaterialsSeat(MatingRing)MaterialsNi-resisthighnickelcastiron;austeniticcastiron高镍铸铁，奥氏体铸铁Ceramic陶瓷材料99.7%aluminiumoxide氧化铝主密封材料PrimarySealMaterialsceramicmatingring主密封材料PrimarySealMaterialsSeat(MatingRing)MaterialsNi-resisthighnickelcastiron;austeniticcastironCeramic99.7%aluminiumoxideSiliconCarbide碳化硅puresinteredorreactionbonded无压烧结或反应烧结TungstenCarbide碳化钨cobaltornickel-bonded钴基或镍基平衡比平衡比BalanceRatio平衡比也称为面积比，指的是机械密封的流体压力作用的有效面积与密封面名义接触面积之比。平衡比的大小反映机械密封的流体压力作用载荷的大小。平衡比B=Af/AhB≥1为非平衡型机械密封，B<1为平衡型机械密封。平衡比BalanceRatio平衡比BalanceRatio平衡比BalanceRatio平衡比BalanceRatio平衡比BalanceRatioBalancediameter平衡直径BalanceRatio平衡比平衡比BalanceRatio1cm20.8cm2Pressure=10kg/cm2125%10050%125%-50%=75%(7.5bar)10075%50%75%-50%=25%(2.5bar)平衡比BalanceRatioMetalbellowsSealsareINHERENTLYbalanced金属波纹管密封固有的平衡型密封平衡比－平衡型机械密封的优点Reducedheatgeneration减少热量生成idealforunstableandlowSGfluids对不稳定的和低密度的液体是比较理想的lessheattobedissipated-lesscoolingrequired产生的热量少，需要冷却的也少Reducedwearrate降低磨损速度longerlife延长使用周期Reducedpowerrequiredtodrivetheseal降低能耗lowerrunningcosts减少运行成本Increasedpressurerangefortheseal增大密封压力范围thissimplemodificationallowsmuchhigherpressurestobesealed这些简单的改变允许大的压力演讲结速，谢谢观赏！Thankyou.PPT常用编辑图使用方法1.取消组合2.填充颜色3.调整大小选择您要用到的图标单击右键选择“取消组合”右键单击您要使用的图标选择“填充”，选择任意颜色拖动控制框调整大小商务图标元素商务图标元素商务图标元素商务图标元素