密封基础知识(基本结构)

1 BasicMechanicalSeals密封基础知识 JCTianjinTraining 2 rotatingsealunit twoflatslidingsurfaces whichmaintainacloserunningclearancewhileseparatedbyafluidfilm两个光滑平面之间维持着一个由流体膜隔开的微小间隙 stationarysealunit Whatisamechanicalseal 什么是机械密封 DesiredFeaturesofaSeal机械密封必须有的特征 Long life很长的寿命Easymaintenance容易检修Lowcost低成本 Smallaxialclearance小的轴向间隙Selfadjusting自调节 ShaftMovement轴的运动 4 BasicMechanicalSeal基础机械密封 Looseringsetscrewedtotheshaft把一个有间隙的环用顶丝固定在轴上 1 5 BasicMechanicalSeal基础机械密封 O ringpreventsleakagethroughthebore 2 6 BasicMechanicalSeal基础机械密封 Springensuresautomaticadjustment弹簧确保自动调整 3 7 BasicMechanicalSeal基础机械密封 4 8 BasicMechanicalSeal基础机械密封 5 9 BasicMechanicalSeal基础机械密封 GasketorO ring SEAT Recirculationforcooling SPRINGORSPRINGFORCE 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一个完整密封的例子 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使密封更加完善的辅助件 12 不像一个机械密封而更像一个限制装置 需要泄漏否则将会灼伤 会磨损轴或轴套高功耗用来克服磨擦产品损失需要大量的水安装 维修和盘根调整需要停车时间泄漏导致设备破坏和摧毁 不可见泄漏 机械密封和盘根之间的泄漏率在1到100或者更好证明机械密封的寿命可达8到10年毫无故障无产品损失 节省水和能量可以节省成本安装后维修很少密封有潜在危害的物质时机械密封可以提供更好的安全性 GlandPackingv MechanicalSeals盘根和机械密封 13 SPRINGFORCEFLUIDPRESSURE fluidfilm 3 5microns athinfilmofliquidformstheprimary dynamic sealbetweentherotatingandstationaryelements在旋转件和静止件之间形成很薄的液膜 FILMREACTION PrimarySeal主密封 14 Faceslappedflattowithin1 3lightbands PrimarySeal FilmThickness主密封 膜厚度 15 PrimarySeal FilmThickness主密封 膜厚度 Fluidfilmthicknessisveryimportanttoothin wear causingearlysealfailuretoothick visibleleakageMustbe present bewaredryrunning谨防干运转Stable稳定谨防磨损征兆clean bewareabrasivewearsymptomsreasonableviscosity合理的黏度temperaturecontrolled受控的温度acceptablepressure允许的压力 16 PrimarySeal FaceFlatness主密封 平面 Iffacesnotflat contactgeneratesheatExcessivewear shortlife 1lightband 0 0000116inchor0 0003mm 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 20 常用动环材料 Face PrimaryRing Materials动环材料Carbon graphite碳石墨类resinimpregnated树脂浸渍 171 antimonyimpregnated金属锑浸渍 218 CarbonconvertedtoSiliconCarbide硅化石墨 121 CVR化学汽相反应硅化石墨CVD化学汽相沉积硅化石墨SolidSiliconCarbide碳化硅Sinteredsiliconcarbide无压烧结碳化硅 277 Reactionsiliconcarbide反应烧结碳化硅 088 Sinteredsiliconcarbidewithcontrolledporosity微孔碳化硅 584 TungstenCarbide碳化钨Cobaltbonded钴基碳化钨 025 Nickelbonded镍基碳化钨 005 21 常用静环材料 Seat MatingRing Narrow Materials静环材料Ceramic陶瓷99 7 AluminiumOxide氧化铝 059 SolidSiliconCarbide碳化硅Sinteredsiliconcarbide无压烧结碳化硅 277 Reactionsiliconcarbide反应烧结碳化硅 088 Sinteredsiliconcarbidewithcontrolledporosity微孔碳化硅 584 TungstenCarbide碳化钨Cobaltbonded钴基碳化钨 025 Nickelbonded镍基碳化钨 005 22 SecondarySeal二次密封 Threebasicforms三种基本形式o ringso型圈Wedges楔形环Bellows波纹管Elastomer橡胶的Metal金属的Formed成型的edgewelded焊接的PTFE TwogroupsPusher推进式Sliding滑移o ringswedgesNon pusher非推进式Bellows风箱 TeflonBellows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 SecondarySealingElements二次密封 Pusher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 Pushervs Non Pusher推进式 非推进式 25 SecondarySeal Pusher二次密封 推进式 Asthefacemovesforwardtotakeupwear theo ringmovesforwardwiththeface pushedbythehydraulicandspringpressures 26 SecondarySeal Pusher二次密封 推进式 Advantages优点suddenfailureveryunlikely几乎不会突发意外事故higherpressurecapability facenotstressed耐压性能高 应力变形小widechoiceofmaterialsforallcomponents所有成分的材料选择广泛fieldrepairable可修复的Disadvantages缺点hang up notlikelywhereo ringiswellisolated 挂起permanentset pressureproblems causehang up 长久放置 压力问题 导致挂起 excellentshaftsurfacefinishrequired要求轴的表面光滑maximumtemperature 260 C最高温度 260 C 27 PusherSeal Hang up推进式密封 挂起 Productleakagesolidifies crystallises polymerises Preventso ringpushingforward leakageincreases阻止O形圈迅速的推进 泄漏增加 Anexternalquenchwillpreventhang up外部的冲洗可防止挂起 28 SecondarySeal O Ring二次密封 O型圈 Type8B1 29 SecondarySeal Wedge二次密封 楔形环 30 SecondarySeal Non Pusher二次密封 非推进式 Bellowsflexestotakeupwear misalignmentandaxialplay Finemachinedshaftsurfacerequired精掣轴表面Donotusea good lubricant neverusesilicongrease 31 SecondarySeal Bellows二次密封 波纹管 32 SecondarySeal MetalBellows二次密封 金属波纹管 statico ring静止o型圈 33 Type10T Type10R SecondarySeal PTFEBellows二次密封 PTFE波纹管 TertiarySeal三次密封 35 TertiarySeal三次密封 Preventsleakageroundmatingring防止静环周围的泄漏Sometimesalsopreventsmatingringrotation有时也防止静环旋转 36 TertiarySeal三次密封 Fourbasictypes四种基本的形式O ringsO型圈Elastomers橡胶SeatRings squareorrectangularsection PTFEgraphiteCupRingselastomersGasketsorFlatJointsPTFEcompressedfibre非石棉的压缩纤维 TertiarySeal O ring三次密封 O型环 TertiarySeal O ring三次密封 O型环 TertiarySeal O ring三次密封 O型环 40 TertiarySeal SeatRing三次密封 静环 TertiarySeal CupRubber三次密封 SpringDesignFeatures弹簧设计特点 Springs弹簧ProvideTheInitialClosingForce提供初始闭合力AreVeryImportantAtLowPressures低压下很重要AreNotSoImportantAtHighPressures高压下不重要 DesignFeatures设计特点 Springs弹簧Single单弹簧Multiple多弹簧Bellows波纹管Wave波形 DesignFeatures设计特点 Springs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 DesignFeatures设计特点 Springs弹簧Corrosion腐蚀Clogging堵塞UniformityOfLoad负荷一致Inventory批量 DriveMechanism驱动机械MustTransmitTorque必须能够传递转矩MustAllowAxialMovement PrimaryRing 必须能够使动环轴向运动 TypesofDriveMechanisms驱动机械的类型 PinDrive销驱动 DentDrive凹窝驱动 SlotandEar槽和支耳 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 TypesofDriveMechanisms驱动机械的类型 48 SealMaterials密封材料 MaterialConsiderations材料需要考虑Temperature温度ThermalExpansion热膨胀ThermalConductivity导热性ChemicalResistance化学稳定性Wear磨损性Flexibility弹性Manufacturability制造能力Cost成本Availability实用性 49 PrimarySealMaterials主密封材料 Face PrimaryRing Narrow Materials窄环材料Carbon graphite炭 石墨resinimpregnated浸渍树脂antimonyimpregnated浸渍金属锑CarbonconvertedtoSiliconCarbide硅化石墨 50 PrimarySealMaterials主密封材料 CarbonconvertedtoSiliconCarbide 51 Solid