Sealing Systems For PumpsSealing Systems For …

1 SARBS Pump Maintenance Seminar, June 7, 2012 Sealing Systems For PumpsSealing Systems For Pumps Part IPresented by:Shelby ScottShelby ScottWestern Region John Crane IncJohn Crane, IncSARBS Pump Maintenance Seminar, June 7, 2012 PackingMechanical Seal BasicsPros & Cons: Packing & SealsgMechanical Seal ElementsBasic Seal DesignsBasic Seal DesignsMaterials of ConstructionSARBS Pump Maintenance Seminar, June 7, 2012 AtmosphereVessel pWallShaftProcessProcessFluidLeakageSARB S Pump Maintenance Seminar, June 7, 2012 Pump HousingAtmospherePump HousingImpellerPackingLeakageShaftgProce ssFluidNote: Leakage occursNote: Leakage occurs in a direction parallel to the shaftClean Process Fluid Acts as Lubricant Between Packing & SleeveAtmosphereBetween Packing & SleeveAtmosphereTargetPumpedFluidTargetL eakage:30 -60 dropsper minuteellerFluidStuffing BoxGlandCooling and Lubricationper minuteImpgTypical Packing SupportTypical Packing SupportFlush Water Pressure Higher Than "A"AtmosphereHigher Than "A"PumpedFluidTargetLeakage.

2 3060 dropsmpellerStuffing Box30 -60 dropsper minuteGlandLtImGlandLantern Ring"A"Often Clean Flush Is Used To Cool &Often, Clean Flush Is Used To Cool & Lubricate Inboard & Outboard Packing RingsAlternateSealing Methodsg& SupportppPackingPackingDie-Formed Packing Ring SetsDieFormed Packing Ring SetsPre-Consolidated In Die Press To Final Shape Fast installation, minimal leakage at start-up Rings Cut With Bevel Seams Eliminates leak path Eliminates leak pathCut To Exact Shaft Diameter Ensures maximum performance Minimal leakagePackaged In Complete 5 Or 6 Ring Sets Ensures all old rings are removed no left oversMinimize Packing Water UsedStaggered Seam LocationsStart at one o'clock, stagger joints 90 degrees, and set No Support Packing CombinationPacking Combination1625G / G57 Mixed set for no water support applicationsG57flexible graphite with corners of carbon G57 -flexible graphite with corners of carbon yarn, provide sealability, self lubricating 1625G - graphite yarn with PTFE, act as bull rings kflibl hifdito keep flexible graphite from extruding1625GG57 Packing vs.

3 Mechanical SealsPacking vs. Mechanical SealsIs not a seal but rather a restricting device. Requires leakage or it will burnWill seal with invisible leakage. On difficult applications theleakage or it will burn. Will groove and wear shafts and sleeves. On difficult applications the leakage ratio between seals and packing is 1 to 100 or better. Slh b k8 High horsepower load to overcome lossSeals have been known to run 8 to 10 years without savings from little toProduct large amounts of water for savings from little to no product loss, water savings and energy maintenance time and downtime for installations and packing maintenance required after initial offer better safety whenEquipment damaged and destroyed from offer better safety when Sealing potentially hazardous Pump Maintenance Seminar, June 7, 2012 PumpLeakageAtmospherePump HousingShaftLeakage diltProcessFluidperpendicular to shaft centerline Mechanical Seal Face LubricationMechanical Seal Face LubricationSurfaces in ContactSurfaces in Contact Fluid Migrates Through Low Areas Provides Lubrication to Reduce Heat Absorbs Heat Generated Surface Wears as Peaks Broken OffFluid MigrationMagnified Surface AHeated Fluid MigrationMagnified Surface BVaporMagnified Surface B1.

4 Primary Sealing ElementsMinimizing LeakageSARBS Pump Maintenance Seminar, June 7, 2012 Close clearance = less leakage and increased wearggg Greater clearance = more leakage and less wearleakage and less seal face film thickness isTypical seal face film thickness is 10-50 -in (micro-inches).A typical piece of paper is 5,000 -in thick!Without Lubrication, SlF R D AdO htSeal Faces Run Dry And Overheat SlStuffing BoxNo Fluid or Dry RunningSealGlandStuffing Boxoudo yu gRotating FaceStationary FaceLack Of Lubrication Causes,Contact, Heat Generation & WearSeal Face Damage: Heat CheckingSeal Face Damage: Heat CheckingSeal FaceWearFront ViewGrooveCracks DueTo InadequateCoolingSARBS Pump Maintenance Seminar, June 7, 2012 Mechanical Seal Sealing Sealing hardware elementsSARBS Pump Maintenance Seminar, June 7, 2012 Drive ElementsAdaptive HardwareLoad ElementPrimary Seal ElementsSecondary Seal ElementsPrimary Seal ElementsSecondary Seal ElementsSARBS Pump Maintenance Seminar, June 7, 2012 Primary RingRetainerDiscDrive BandMating RingO-RingSpring Adaptorat ggSpringElastomer BellowsSARBS Pump Maintenance Seminar, June 7, 2012 Two Basic Seal Designs Exist: Bellows seals.

5 More flexible, no dynamic O-ring, clog-resistant O-ring seals: compact, higher pressures, wide chemical rangebellows made from rubber, metal or PTFE O-ring SealBellows SealO-ring slidesin process fluidstatic sealhereflexible bellowshead hereSARBS Pump Maintenance Seminar, June 7, 2012 The Ideal Material for Mechanical Seals: corrosion resistant wear resistant wear resistant rugged design non deflectingWaste Water Seal: Silicon Carbide / Silicon Carbide or Tungsten Carbide / Tungsten CarbideCl Wt S lCb /Sili CbidCb /Clean Water Seal: Carbon / Silicon Carbide or Carbon / Tungsten CarbideSARBS Pump Maintenance Seminar, June 7, 2012O iMi l fEffi iS liOptimum Materials for Efficient Sealing Hard Face Silicon Carbide Ceramic ( Al-Oxide)Ceramic ( AlOxide) Tungsten Carbide Soft FaceCb Carbon Bellows Viton Buna EPDMM etal Parts and Spring Metal Parts and Spring 304 SS ( 18-8) or 316 Stainless SteelSARBS Pump Maintenance Seminar, June 7, 2012 SSelfelf--Cleaning Effect of Rotating SealCleaning Effect of Rotating SealResistance to packing and adhesion by the product to the rotating memberSARBS Pump Maintenance Seminar, June 7, 2012 Seal Survival Depends on Cooling / Lubrication Heat Generated at Faces due to Friction S Liquid Around Seal Provides Lubrication Liquid Also Removes Heat Dry-Running Will Result in Quick FailureSARBS Pump Maintenance Seminar, June 7, 2012 Part I - The End!

6 !!Questions???Questions???Tom Nowak West Region Engineering ManagerOffice # Chavez Sales # Pump Maintenance Seminar, June 7, 2012 Sealing Systems For PumpsSealing Systems For Pumps Part IIPresented by:Shelby ScottShelby ScottWestern Region John Crane IncJohn Crane, IncSARBS Pump Maintenance Seminar, June 7, 2012 Seal TypesSeal Types Causes of Seal Failure Piping PlansSealing Water UsageggSafeunit FlowmetersSARBS Pump Maintenance Seminar, June 7, 2012 Type 21 Type 1 SARBS Pump Maintenance Seminar, June 7, 2012 Pump TypesPump TypesSewage PumpSubmersible PumpSARBS Pump Maintenance Seminar, June 7, 2012 Dual Seal Arrangement Inboard Seal Prevents Leakage of Process Water Outboard Seal Prevents Leakage Into MotorInto Motor Oil Between Seals Provides OutboardProvides Outboard Seal SupportSARBS Pump Maintenance Seminar, June 7, 2012 Waste Water ApplicationsSARBS Pump Maintenance Seminar, June 7, 2012 Waste-water pumpSARBS Pump Maintenance Seminar, June 7.

7 2012 Mechanical Seals for Waste Water Applications Mainly Single Springs Mainly Single Springs Self-Cleaning Effect Due to Rotating Spring Face Materials Need High Resistance Chemicals Chemicals Abrasion Elastomers to be Chemical ResistantSARBS Pump Maintenance Seminar, June 7, 2012 Factors influencing leakage Seal face condition Running-in process Process influences Stability of seal face Condition of the secondary seals Face deformation caused by temperature and pressure Vibration and stability of the machine Operating mode of the plant Characteristics of the sealed fluids Accuracy of the seal mounting and assembly Condition of the equipmentSARBS Pump Maintenance Seminar, June 7, 2012 Failure Causes at Mechanical Seal Insufficient venting atLiidGas ringLiquid/ Gas mixture Insufficient venting at Mechanical Seal Vaporization of media in seal gapLiquidg Negative pressure in stuffing box Air bubbles in piping tfbffrotierendstation rrotating stationary system of pump or buffer fluid systemHindered heat transfer due to gas ringSARBS Pump Maintenance Seminar, June 7, 2012 Failure of Mechanical SealDry running at start up of pump, insufficient ventingFaces are dull and slightly shiny, Bellows at seal face melted and withcracksCause of failure:Observations: Vent pump sufficient Checklist for start upSolution: Train staffWaste water10 PSIP ressureMedia90 FSpeedTemperature1750 RPMSARBS Pump Maintenance Seminar, June 7, 2012 Failure of Mechanical SealFailure of Mechanical SealCause of failure.

8 Dry running at start up of pump, insufficient ventingFaces dull and with traces, selective corrosionObservations: Fill and vent Pump before start up Check material selection, at pH-Value <7 use SiCSolution:pWaste Water with 3% Solids45 PSIP ressureMedia75 - 90 F 1780 RPMS peedTemperatureSARBS Pump Maintenance Seminar, June 7, 2012 Thll d f fdti tifFailure of Mechanical SealCause of failure:Thermal overload of faces due to vaporization of media in seal gap, Operation near boiling pointObservations:Faces dull and with clear running traces and blistering. Elastomers : increase pressure lower temperatureWastewaterSMedia190 FApprox 25 PSI3500 RPMP ressureSpeedTemperatureFlush Plan 11 - Circulation from DischargeSARBS Pump Maintenance Seminar, June 7, 2012 Circulation Pipe From Discharge to Seal ChambergDischargeDischarge to Seal ChamberSuctionSuctionSingle Mechanical SealFlush Plan 13 - Circulation to SuctionSARBS Pump Maintenance Seminar, June 7, 2012 Circulation Pipe From Seal Chamber to SuctionDischargeChamber to SuctionSuctionSuctionSingle Mechanical SealPlan 31 Cyclone SeparatorSARBS Pump Maintenance Seminar, June 7, 2012 DischargeClean fluid to sealAbrasives back to suctionSuctionSuctionSingle Mechanical SealPlan 32 - External Source FlushHigher PressureSeal Water IsSARBS Pump Maintenance Seminar, June 7, 2012 DischargeMinimum Pressure5psi/ 3barSeal Water IsThe Seal FaceLubricant A5 psi /.

9 3 bar Above A SuctionSeal Water FlowASuctionSingle Mechanical SealSealing Wate UsageSealing Water UsagePacking / Seals Typically Supplied 5 - 10 gpmPacking Typically Needs Only 1 gpmSlTillNdOl Seals Typically Need Only gpmSupply Only The Amount That s Needed!Supply Only The Amount That s Needed!Safe nit Sealing Wate S stemSafeunit Sealing Water SystemComplete system ToComplete system To Control Sealing Water Flow & PressureMonitors Water Supply &Monitors Water Supply & Indicates TroubleUsed With: Packing Single seals Quench seals Double sealsQuick Cleaning Without Interrupting Water FlowpgOptional AlarmSafe nit T pesSafeunit TypesSFPP acking orSingle Seal FlushSingle Seal FlushSFQSFQQ uench SealsSFDDblSlDouble SealsPlan 32 - External Source FlushType SFPSARBS Pump Maintenance Seminar, June 7, 2012 DischargeSafeunit ToReduce UseTo gpmMinimum Pressure5psi/ 3barType SFPS afeunitTo gpmA5 psi /.

10 3 bar Above A Seal Water FlowSuctionASeal Water FlowSuctionSingle Mechanical SealPlan 54 - External Source BarrierSARBS Pump Maintenance Seminar, June 7, 2012 Hot BarrierOut (Top)Minimum Pressure20 psi / 1 2 barDischargeType SFDS afeunitA20 psi / bar Above A SuctionASeal Water FlowSuctionDoubleMechanical SealCool Barrier In (Bottom)O-Ring Style Split SealORing Style Split SealFast Easy InstallationFast, Easy Installation Cartridge Split SealDowntime ReducedTo A MinimumFor Typical PumpsNlFi SiNon-clog Finger SpringsPreinstalled O-ringsVacuum To 200 psiVacuum To 200 psi Pressure RangeUp To 3600 rpmppBellows Style Split SealBellows Style Split Seal Bellows accommodates large shaft runout (~.125 )Nitli No o-rings or metal springs to clog or hang Pump Maintenance Seminar, June 7, 2012 Part II - The End!!!Questions???Roger Chavez Western Region Offi# 5628022555 Office # 562-802-2555 Cell #