《机械密封培训》PPT课件.ppt

西部管道密封培训,JohnCrane Tech(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,机械密封基础 第一部分,Concepts of Mechanical Seals机械密封概念,Shaft,Process Fluid密封流体,Leakage泄漏,Environment环境,Vessel Wall釜壁,The Basic Sealing Problem:Preventing Leakage基本的密封问题:防止泄漏,Shaft,Process Fluid流体流动,Leakage泄漏,Environment环境,Vessel Wall釜壁,The Concept of anEnd Face Mechanical Seal机械密封端面的概念,Shaft Movement轴的运动,Required Features必须的特征,Small axial clearance小的轴向间隙Self adjusting自调节,Mating Ring配合环,Primary Ring补偿环,Secondary Sealing Element辅助密封,A Flexible Seal Flexible 机械密封,Hydrostatic loading流体静力学负荷Secondary sealing elements辅助密封Replaceable parts可替换的部件,O-Ring O型圈,Shaft轴,Mating Ring配合环,Primary Ring补偿环,Snap Ring卡环,Anti-X Ring 挡环,O-Ring O型圈,Disk推环,Springs弹簧,Retainer传动套,Set Screw定位螺丝,An Example of a Complete Seal,Simply put,a mechanical seal is:简单的说,机械密封就是:,1.A wearable,stationary,primary sealing element 一个耐磨,静止的密封件2.A wearable,rotating,primary sealing element 一个耐磨,旋转的密封件3.A secondary sealing element 二次密封4.A mechanical loading device to press primary sealing elements 1 and 2 against one another,and 使件1和件2相互贴合的机械装置5.Auxiliary components to complete seal 辅助密封,Non-flashing没有闪蒸,Flashing闪蒸,Parallel平行,Converging收敛,Diverging发散,Face Separation密封面分离,Shape:形态,Gap:间隙,Fluid:流体,The Sealing Interface密封接触面,Lubricant润滑剂,Separation分离面,Magnified Surface A 放大面,Magnified Surface B放大面,Heat热量,The Sealing Interface密封面,Lubrication Purpose:润滑目的Separate surfaces分离两个面Prevent contact of high surface points防止出现面接触Reduce friction/heat generation减少摩擦/生热,Process Fluid Acts as Lubricant Between Faces流体在两个面之间充当润滑剂的过程,Gland密封端盖,Pump Housing泵腔,Process Fluid工艺流体,Invisible Leakage:不可见泄漏Fluid Evaporates Upon Reaching Atmosphere微量的泄漏在大气侧蒸发,Primary Ring补偿环,Mating Ring配合环,Gland密封端盖,Pump Housing泵腔,No Fluid Or Dry Running没有流体或者干运转,Primary Ring补偿环,Mating Ring配合环,Without Lubrication,Faces Run Dry And Overheat 没有润滑干运转导致过热,Mating Ring配合环,Primary Ring补偿环,Heat Generation 生热,Rubbing摩擦Viscous Shear粘性剪切力,Heat Transfer热传递,Conduction传导Convection对流,Injection注入,Flushing冷冲洗,Removes Heat带走热量Replenishes Cool Clean Lubricating Liquid 补充润滑液,Primary Seal:Flush基本密封:冲洗,Single Seal Flushing By-Pass from Discharge(API Plan 11)单密封通过出口进行冲洗,By-pass Line fromPump Discharge to Seal Gland 从泵出口到密封端盖的管线,Discharge出口,Flow流动,Suction入口,Primary Seal:Flush基本密封:冲洗,Minimum Pressure.3 bar/5 psi Above A?最小压力值要大于A处0.3Bar,Flow流动,Discharge出口,Suction入口,Restrictional Device(Bushing)限流装置,Single Seal Flushing from External Source(API Plan 32)单密封通过外部来源进行冲洗,A,Primary Seal:Quench 基本密封:急冷,Restrictional Device(Packing)限流装置(盘根),Quench Source急冷源,Process Fluid工艺流体,Single Seal Quench from External Source(API Plan 62)单密封通过外部急冷,API Piping PlansAPI 冲洗方案第二部分,JOHNCRANE,API Piping Plans API 冲洗方案,Integral(internal)recirculationfrom pump discharge to seal内部循环从泵的出口到密封,Advantage 优点-No external piping 没有外部冲洗 Limitations 局限性-Changing flow rate required dismantling of pump 改变流量需要拆泵-For clean pumpages only 只能是适用干净的介质,API Piping Plans API 冲洗方案,Points to Note for API Plan 02:API 02 冲洗方案应注意的事项：The injection tapping is used for venting prior to startup.-在开车前，入口用来进行放空API plan 02 is often used together with plan 62,especially on high temperature bellows seals.冲洗方案2经常与62一起用，特别是用在高温波纹管密封,API Piping Plans API 冲洗方案,No flushing to the mechanical seal(dead-ended)机械密封里没有冲洗,Points to Note for API Plan 11:API 冲洗方案11 应注意的事项-Use an orifice to restrict the flow rate if the discharge pressure is 3 bar higher than seal chamber pressure.如果出口压力高于密封腔压力3bar，需要用一个孔限制流量-Use on clean and low abrasives duties用在干净，含磨石性颗粒少的工矿,API Piping Plans API 冲洗方案,Seal Flushing By-Pass from Discharge单密封通过出口进行冲洗,Recirculation from seal chamber through a flow control orifice and back to pump suction从密封腔里出通过一个孔板返回到泵的入口,Points to Note for API Plan 13:API 冲洗方案 13 应注意的事项-Use an orifice to restrict the flow rate if the seal chamber pressure is 3 bar higher than suction pressure.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-handle abrasives duty better than API plan 11处理含有磨石性颗粒的工矿13方案号优于11方案-higher seal chamber pressure to suppress vaporisation较高的密封腔压力可抑制它的汽化,API Piping Plans API 冲洗方案,+,=,Points to Note for API Plan 14:API 冲洗方案 14 应注意的事项：-Flow back to suction side will evacuate vapours that may collect in seal chamber.-Recommended for light hydrocarbon service.,API Piping Plans API 冲洗方案,Recirculation from pump discharge through a flow control orifice and cooler to sealOpen Loop Cooling Circuit,Cooling Water Outlet冷水出口,Cooling Water Inlet冷水入口,API Piping Plans API 冲洗方案,Recirculation from a pumping ring in the seal chamber through cooler and back to seal Closed Loop Cooling Circuit 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,Throat bushing,Suction入口,Discharge出口,18-24,Vent at highest point of the piping排气在管线的最高点,Cooling Water Outlet冷水出口,Cooling Water Inlet冷水入口,mechanical seal with pumping ring,Heat exchanger换热器,API Piping Plans API 冲洗方案,Points to note for API Plan 23:Thermosyphon design热虹吸设计*heat exchanger 换热器 18 to 24“above pump centre line.在泵中心线以上 18 to 24*Prevent overheating in standby and startup.*在泵启动和备用时，要防止过热。Install close fitting neck bushing at the bottom of seal chamber to isolate the heat from the impeller end.在密封腔底部安装喉部衬套用来隔离从叶轮传出的热量Used on high temperature applications to minimise heat load on the cooler by cooling only small amount of liquid that is recirculated.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.For high temperature boiler feed pump applications用于高温锅炉给水泵上Other applications其他应用*high temperature liquid close to bubble point.*接近沸点的高温液体.,API Piping Plans API 冲洗方案,Recirculation from pump discharge through a cyclone separator delivering clean fluid to the seal and fluid with solids back to pump suction line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,API Piping Plans API 冲洗方案,Points to Note for API Plan 32:对于API plan 32 须注意:-Chose a proper source of seal flush to eliminate the potential for vaporisation of the injected fluid and to avoid contamination of the fluid being pumped with the injected flush.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。-Install a labyrinth bushing at the bottom of the stuffing box to control the flushing and pressure if necessary.-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。,API Piping Plans API 冲洗方案,Single Seal Flushing from External Source单密封通过外部来源进行冲洗,Throat Bushing,Recirculation from pump discharge through a cyclone separator delivering clean fluid through a cooler and then to seal and fluid with solids back to pump suction line,Cooling Water Outlet,Cooling Water Inlet,API Piping Plans API 冲洗方案,Needle valve,External reservoir providing a dead-ended blanket of fluid to the quench connection of the gland.,Points to Note for API Plan 51:对于API plan 51 须注意:-Dead ended blanket on atmospheric side of seal to prevent freezing of moisture.Seal face will not stick together when the pump started.-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。Typical application:典型的应用Pump operating below 0 C应用于泵在 0C以下-API 610 8th Edition has eliminated this piping plan.API 610 第八版已经取消这个冲洗方案-,API Piping Plans API 冲洗方案,Piping Systems,API Piping Plans API 冲洗方案,A fluid used as a lubricant or buffer between dual mechanical seals.这种液体象缓冲剂，润滑剂用在双机械密封 The buffer fluid is always at a pressure lower than the pump process pressure being sealed.缓冲液的压力通常低于被密封的介质的压力,A fluid which is introduced between dual mechanical seals to completely isolate the pump process liquid from the environment.双机械密封里的隔离液用于是泵的工艺液体与大气分离 Pressure of the barrier fluid is always higher than the pump process pressure being sealed.隔离液压力总是高于泵的运作压力,The purpose of fluid circulationis to remove heat from mechanical seal,API Piping Plans API 冲洗方案,On applications below ambient temperature,circulation of barrier fluid may not be desirable.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。The atmosphere will heat the reservoir and consequently add heat to the seal area.外部对储罐进行加热，从而，对密封区域进行加热。,Fluid circulation by temperature difference between the seal and reservoir.流体依靠密封腔和储罐的温差进行循环 Higher temperature liquid at seal has lower density rises to the reservoir.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 Lower temperature liquid at reservoir has higher density falls to the seal to provide cooling.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,External Force Circulation,Thermosyphon,Pumping Ring,Dead Ended,API Piping Plans API 冲洗方案,Points to Note for API Plan 52:Typically used with an Arrangement 2 unpressurised dual seal.通常用于不带压双封 During normal operation,circulation is maintained by an internal pumping ring.在正常操作情况下，通过腔内的泵效环维持循环 The reservoir is usually continuously vented to a vapour recovery system and is maintained at a pressure less than the pressure in the seal chamber.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,Pressure Gauge 压力计,Level Gauge 水准仪,Fill valve,Orifice,Drain,Level Switch(H)电平开关,Level Switch(L),Pressure Switch 压力开关,(Normally Open),Vent valve 排气阀,External reservoir providing buffer fluid for the outer seal of an unpressurised dual seal arrangement.外部储罐对不带压双封的外密封起缓冲液的作用,API Piping Plans API 冲洗方案,Pressure Gauge 压力表,Level Gauge 水准仪,Level Switch(L)电平开关,Vent Valve 排气阀(Normally Close)通常关着,Orifice,Pressure Switch 压力操纵开关,External Pressure 外部压力 Source,One-way Block Valve(Normally Open),Points to Note for API Plan 53:Typically used with an Arrangement 3 pressurised dual seal.通常用于带压双封 During normal operation,circulation is maintained by an internal pumping ring.在正常操作情况下，通过腔内的泵效环维持循环 The reservoir pressure is greater than the process pressure being sealed.罐内压力通常高于被密封介质压力,External reservoir providing pressurised barrier fluid for the outer seal of an pressurised dual seal arrangement.外部储罐对带压双封的外密封起隔离液的效果,Drain,API Piping Plans API 冲洗方案,Points to Note for API Plan 54:Typically used with an Arrangement 3 pressurised dual seal.通常用于带压双封During normal operation,circulation is maintained by an external pump or pressure system.在正常操作情况下，通过外部的泵或压力系统维持循环 The circulating barrier fluid pressure is greater than the process pressure being sealed.循环隔离液的压力高于被密封介质的压力,External barrier fluid system providing pressurised barrier fluid for the outer seal of an pressurised dual seal arrangement外部隔离液系统对带压双封的外密封提供带压隔离液,API Piping Plans API 冲洗方案,Safe to use,handle,store储藏、操作、使用安全可靠Stable liquid at ambient temperatures在室温下，性能稳定 Not a VOC,VHAP or other regulated compound不易挥发、非有毒物质Non flammable不易燃烧Non foaming when pressurised高于常压时，不易起泡Clean and good lubricity干净且有较好的润滑性Compatible with process fluid与工艺流体有互容性Compatible with seal materials与密封材料相一致Good heat transfer properties有好的传热性能 Good flow qualities at very low temperatures 在低温下，有好的流动性Low solubility of gas对气体有较低的溶解性Local availability当地容易获得Low cost成本低,VOC:Volatile Organic CompoundVHAP:Volatile Hazardous Air Polutants,Selection of Buffer/Barrier Fluid,API Piping Plans API 冲洗方案,Tapped connections for the purchasers use在接口处攻螺纹，以方便用户使用,Point to Note for API Plan 61:对于API plan 61 须注意:Typically this plan is used when the purchaser is to provide fluid(such as steam,gas,or water)to an auxiliary sealing device.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,API Piping Plans API 冲洗方案,Points to Note for API Plan 62:对于API plan 62 须注意:The quench may be required to prevent solids from accumulating on the atmospheric side of the seal.增加吹扫口以防止在密封大气侧有颗粒的积累Typically used with a close-clearance throttle bushing.普遍使用节流衬套,API Piping Plans API 冲洗方案,Single Seal Quench from External Source单密封通过外部急冷,API 682 2nd Edition API 682 第二版New Piping Plans 新的冲洗方案,Plan 14(Plan 11+13)冲洗方案14Plan 53s-Arrangement 3,Contacting Wet(CW)Seals 53 方案-排列方案3，接触式湿密封53a traditional configuration 传统构造53b bladder accumulator 蓄能器53c piston pot/accumulator 活塞/蓄能器Containment Seal 二次辅助密封Plan 72 Arrangement 2 w/Containment Seal(CS)Plan 75 Arrangement 2 w/Containment Seal(CS)Plan 76 Arrangement 2 w/Containment Seal(CS)Gas Barrier Seals 气体Plan 74 Arrangement 3,Non-Contacting(NC)Seals排列方式3，非接触式密封,Plan 53a(A.4.12),Arrangement 3,Contacting Wet(CW)Seals排列方式3，接触式湿密封Dual Pressurised(Double)Seals 带压双封Utilises direct nitrogen blanket for pressure利用氮气层来增压due to nitrogen entrainment in the barrier liquidAPI 682 limits the maximum nitrogen pressure to 10 barg,JC recommendation is maximum nitrogen pressure 21 barg,as long as the barrier fluid temperature is less than 120C API 682 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,API 682 2nd Edition API 682 第二版 New Piping Plans 新的冲洗方案,Plan 53b(A.4.12),Arrangement 3,Contacting Wet(CW)Seals 排列方式3，接触式湿密封Dual Pressurised(Double)Seals 带压双封Utilizes bladder accumulator for pressure 利用蓄能器来增压Bladder eliminates nitrogen contact with barrier liquid蓄能器把氮气与隔离液分开Allows for higher pressure applications 允许高压力应用,Configuration Includes:Accumulator 蓄电池Pressure Indicator 压力显示器Pressure Switch压力开关Heat Exchanger换热器,API 682 2nd Edition API 682 第二版New Piping Plans 新的冲洗方案,Plan 53c(A.4.12),Arrangement 3,Contacting Wet(CW)Seals排列方式3，接触式湿密封Dual Pressurised(Double)Seals 带压双封Utilizes piston pot for pressure 利用活塞增压,API 682 2nd Edition API 682 第二版New Piping Plans 新的冲洗方案,Plan 53c(A.4.12),Allows for higher pressure applications 允许高压力应用Configuration includes:构造包括Piston pot 活塞Pressure indicator压力显示器Pressure switch 压力开关Heat exchanger换热器Level switch电平开关,Piston pot eliminates nitrogen contact with barrier liquid活塞缸阻断了隔离液与氮气的连接Piston provides constant pressure ratio to seals(1.1:1)活塞给密封提供持续的压力比率,Spring 弹簧,API 682 2nd Edition API 682 第二版New Piping Plans 新的冲洗方案,Barrier Fluid Temperature(7.3.4.1.1)隔离流体温度,Liquid barrier systems shall be designed such that that maximum temperature differential between the barrier fluid inlet and outlet immediately adjacent to the seal chamber is: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8 degree C for glycol/water or diesel barrier fluids;and 对于水，乙二醇，柴油隔离液，允许最大温差8度16 degree C for mineral oil barrier fluid 矿物油隔离液 允许最大温差16度,Plan 11 with Plan 53,Arrangement 3 may use Plan 11&53 排列方式3可以用11&53方案Improved heat transfer 增加换热Reverse pressure capability 压力转换能力“Back to Back”seals uses Plan 53背对背密封用53方案,API 682 2nd Edition API 682 第二版New Piping Plans 新的冲洗方案,Plan 72(A.4.16),Arrangement 2,w/Containment Seal(CS)排列方式2，辅助二次密封Dual Un-Pressurised(Tandem)Seals 不带压双封Dry-running secondary containment seal 干运转二次辅助密封Low pressure nitrogen sweep(purge)低压氮气吹扫Sweeps primary leakage to collection system 主密封泄漏的东西排放到收集系统里Dilutes primary leakage to lower emission levels 稀释泄漏的东西Used in conjunction with Plan 75 or 76，与75方案获76方案一起使用,CSV:containment seal ventCSD:containment seal DrainGBI:gas buffer inletFIL:coalescing filter,API 682 2nd Edition API 682 第二版New Piping Plans 新的冲洗方案,Plan 74(A.4.17),Arrangement 3,Non-contacting Seals(NC)排列方式3，非接触式密封Dual Pressurised(Double)Gas Barrier Seals 带压Nitrogen gas barrier 氮气隔离1.75-2 bar(25-30 psi)above seal chamber pressure密封腔压力1.75-2barZero emissions 零泄漏Essentially a T2800 panel 2800类型控制面板,GBI:gas buffer inlet GBO:gas buffer outlet(NC)(used only to depressurize),API 682 2nd Edition API 682 第二版New Piping Plans 新的冲洗方案,Plan 75(A.4.18),Arrangement 2,w/Containment Seal(CS)排列方案2，二次辅助密封Dual Un-Pressurised(Tandem)Seals 双无压密封Dry-running secondary 辅助密封干运转Condensate collection reservoir(8.6.5.2)冷凝液收集罐Used when primary seal leakage may condense(does not completely vaporize)用于从主密封泄漏出来的可冷凝的工况May be used in conjunction with Plan 72 或许和72方案一起使用,API 682 2nd Edition API 682 第二版New Piping Plans 新的冲洗方案,Plan 76(