Rotary SealsParker Hannin CorporationEPS DivisionToll Free: (800) 233-3900This document, along with other information from ParkerHannin Corporation, its subsidiaries and authorized distributors,provides product and/or system options for further investigation byusers having technical expertise. It is important that you analyze allaspects of your application and review the information concerning theproducts or systems in the current product catalog. Due to the varietyof operating conditions and applications for these products or sys-tems, the user, through his or her own analysis and testing, is solelyresponsible for making the nal selection of the products and systemsand assuring that all performance, safety and warning requirementsof the application are met. The products described herein, includingwithout limitation, product features, specications, designs, availabilityand pricing, are subject to change by Parker Hannin Corporation andits subsidiaries at any time without notice.OFFER OF SALEThe items described in this document are hereby offeredfor sale by Parker Hannin Corporation, its subsidiaries and itsauthorized distributors. This offer and its acceptance are governed bythe provisions stated on the separate page of this document entitledOffer of Sale.!WARNING:FaiIure, improper seIection or im-proper use of the products and/orsystems described herein or reIated items can cause death, personaIinjury or property damage.For safe and trouble-free use of theseproducts, it is important that you read and follow the Parker Seal Group ProductSafety Guide. This Safety Guide can be referenced and downloaded free of charge at www.parkerseals.com and can be ordered, without charge, as ParkerPublication No. PSG 5004 by calling1-800-C-PARKER.2006 Parker Hannin Corporation123456789101112IntroductionEngineeringMaterialsProduct OfferingClipper Oil SealsParker Oil SealsShaft SleevesProTech Bearing IsolatorsFlexiLip FlexiCase FlexiSeal RotaryV-Seals and ExcludersRotary SealDesign GuideTable of ContentsChemical CompatibilityInterchangeOther Parker EPS ProductsParker Hannin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comDesign Action Request FormRotary Lip Seal Inch SizesRotary Lip Seal Metric SizesSolid to Split Seal Calculator Inch & MetricSleeve & V-Seal SizesProTech Sizes Inch & MetricConversions Size/Speed/Temp.Chemical CompatibilityInterchangeOther Parker EPS ProductsRotary SealDesign GuideAppendixParker Hannin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comABCDEFGIHJCatalog EPS 5350/USA1-1 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comIInnttrroodduucctti ioonnThe completeness ofParkersproductline allows us toprovide theoptimal designfor any rotatingapplication.Parkers Rotary Sealing Solutions Program providesthe most complete coverage in the industry of shaft seals forrotating applications, for both OEM and MRO requirements.The completeness of the product line allows Parker to providethe optimal design for any given application. Parker is morethan just product. A complete solutions package has beencreated by supplementing the broadest range of productswith full engineering support, strict quality standards, directfactory field support, R&D and premier customer service. AtParker EPS, seals are not an add-on to our business, seals areour only business.ClipperOil SealThe Clipper Oil Seal is the anchor of the rotary sealproduct line. The Clipper design features an integrally moldedrubber fiber outer case and an elastomeric seal lip. Theunique, nonmetallic construction will not rust or corrode andforms a gasket-type seal between the equipment housing andthe seal outside diameter (OD). With a wide range of profilesand material options, Clipper seals are available for shaftdiameters from 0.250" (6.35 mm) to over 65" (1651 mm).Clipper Split Seals are known worldwide for being theeasiest split seal to install because they do not require acoverplate to keep them in the housing. The robust, compositeOD provides the best retention of any split seal on themarket. Replacing failed seals in the field with Clipper SplitSeals saves on downtime and lost production expenses. Tomake replacement even easier, specify Clipper solid seals asthe OEM solid seal. When cutting a metallic seal is required for in-field replacement, there is the the possibility of metalshavings entering the bearing. The non-metallic design of theClipper seal eliminates this possibility.Parker Oil SealParker Oil Seals provide additional coverage and includethe common metal OD construction for inch requirements andrubber covered OD construction for metric requirements.Single lip and double lip profiles are available as well as over100 special profiles for applications with unique operatingconditions. The typical size range is for shaft diameters from0.200" (5 mm) to 10" (254 mm).03/28/06111-2 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comIntroductionCatalog EPS 5350/USAFlexiLip, FlexiCase and FlexiSealFlexiLip, FlexiCase and FlexiSeal PTFE seals extend theParker application range by providing coverage whereoperating conditions exceed the capabilities of elastomeric lipmaterials. Conditions such as high speed and high pressure,and requirements for chemical resistance and low torque areeasily accommodated by one of our 50 standard profiles. The typical size range is for shaft diameters from 0.125"(3 mm) to 16" (406 mm).ProTech Bearing IsolatorsProTech bearing isolators further complement Parkerssolutions program by offering an answer for applicationswhere improving the mean time between failure (MTBF) iscritical. The ProTech family relies on true non-contactlabyrinth seal technology to provide 100% exclusion of contaminants and 100% retention of bearing lubrication forthe life of the bearing. Fourteen standard profiles are availableto allow for ease of retrofitting most equipment. Typical sizerange is for shaft diameters from 0.492" (12.5 mm) to 38"(965 mm). ProTech has also been independently tested toIEEE IP55, IP56, IP66 and IP69k.Quick Sleeve, Wear Sleeve and V-SealsQuick Sleeves, Wear Sleeves and are V-Sealsauxiliary components that provide additional convenienceto the Parker Sealing Solutions Program. Quick Sleeve shaftrepair sleeves and Wear Sleeves are economical, convenient solutions to create proper shaft surfaces.V-Seals can be added as a slinger type seal to protect theprimary seal or used as a primary seal to exclude dirt ingrease applications.03/28/06IntroductionCatalog EPS 5350/USA1-3 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comSeal Decision TreeOil Retention, Shaft Speed under 3,000 fpm (15 m/s)Pages 5-14, 5-26,5-26, 9-1 LUP MIST LifeLine LDN-SPages 8-25, 8-29LW MLEOver 14" OD?Pages 5-27, 8-27R Series Split SLEYesNoPages 5-17, 6-18OL OSBSplit?YesNoBore Rotates?YesNoPressure > 5 psi?YesNoPages 9-10, 5-16 LFN LFE-S MPPages 10-8, 6-15,10-9CFE NSC4 CGEPages 10-85-16, 10-9, CEN CDE HPPage 10-8 CHE CHNPage 11-7, 11-8 FCC FFC< 60 psi< 125 psi< 250 psi< 500 psi< 3,000 psiPages 5-15, 6-17,5-15LUPW SME LDSWHigh Runout?YesNoPages 9-1, 10-1,8-22 LFE CME LSPages 5-14, 6-12,10-1 LDS TB TCPages 12-5, 6-12,6-16 VA + TB TBV CLPages 12-9, 6-12,8-22SSW + TB SB + SB LSPage 6-14 DB DCExcludingContaminantsIs Critical?YesNoChemical ServiceLightContaminantsModerateContaminantsHeavyContaminantsSeparate FluidsPages 5-14, 6-12 LUP SB SC SDPages 9-1, 10-1,5-25, 6-19 LEN CMN TMAL TNGeneralServiceChemicalServiceNote: Intended for use as a general design guide only.03/28/0611 Introduction1-4 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAClipper Oil Seal and Parker Oil Seal ProfilesStyle A Style E Style L Style S BDC BDV BSC BSVCAP CB CH CL Clipper Sliptite DA DB DCDC4 DL DS DM H HP KA KAPKB KBJ KBP KC KC8 KCJ KG KMLDS LDSF LDSW LifeLine LPD LPDSpring RetainerLPDW LUPLUPW MP MIST NSC1 NSC3 NSC4 NTC1 NTC3NTC4 OKA OKB OKC OKM OL OSA OSBOSC OSM OTA OTB OTM OTC OUA OUBOUC OUM OVA OVB OVC OVM P RPDRPDT RUP RUPW SA SAE SAP SB SBFSBJ SBP SC SCE SCF SCJ SD SD2SEC SEM SDS SG SM SME SS SSW03/28/061IntroductionCatalog EPS 5350/USA1-5 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comClipper Oil Seal and Parker Oil Seal Profiles (Continued)STLUP STLUPw/ButtonsST MIST ST MISTw/ButtonsSXA SXB SXC TATAP TB TBF TBH2 TBH4 TBJ TBP TBVTBY2 TBY3 TC TC8 TC12 TCF TCJ TCVTCK TC9 TD TD6 TDN3 TEA TEC TEMTG TG13 TM TMAL TMAS TN TSS UAUB UC VA VAP VB VB1 VB3 VB4VB6 VBJ VBP VC VCJ VG VM VM1VM2 W WPC WPK WPR **L **R **WShaft Seal Profilesd e g n a l f - n o N e v e e l S r a e W d e g n a l F e v e e l S r a e W e v e e l S k c i u QProTech Bearing Isolator ProfilesLS LN WD FS FN SB LBLM LD LW/LX SL ML MN SM03/28/06**Hydrodynamic lip pattern. L = CCW shaft rotationR = CW shaft rotationW = Bi-directional shaft rotation1 Introduction1-6 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAFor additional information on all profiles, see the Product Offering in Section 4.FlexiLip, FlexiCase and FlexiSeal Rotary ProfilesLFN-N LEN-N LDN-N LMN-N LFE-N LEE-N LDE-N LGN-NLFN-S LEN-S LDN-S LMN-S LFE-S LEE-S LDE-S LGN-SCFN CFE CMN CME CEN CEE CDN CDECGN CGE CJN CJE CHN CHE FCC-V FCS-VFCC-C FCS-C FHC-V FHS-V FHC-C FHS-C FFC-V FFS-VFFC-C FFS-C FFN-H03/28/061IntroductionCatalog EPS 5350/USA1-7 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comEngineering ExcellenceEngineering support is another feature of theParker Sealing Solutions Program. Every productgroup is fully supported by Parkers internalengineering staff. As the leader in seal design engineering, Parker designs sealing solutions fornew applications, modifies designs to improveperformance and troubleshoots problem applications in addition to designing like replacements.Quality CommitmentQuality commitment is a feature of theParker Sealing Solutions Program that we takevery seriously. Quality was built around thetough requirements of MIL-I-45208A andMIL-STD-45662 and refined for certification forISO-9001 and AS-9100. All manufacturing plantsare either ISO-9001 or QS-9000 certified to assureconsistent quality.Customer SupportField Service is provided by over 90 directfactory representatives to keep customers up todate on the latest technologies and provide a widerange of on-site services.Research & Development efforts arecontinuous and ensure the latest in sealingtechnology design and materials are available.Testing capabilities allow seal performance to beverified prior to a customer launch of a newproduct.Premier Customer Service is a key componentof the Parker package. Electronic orderingsystems such as EDI and PHconnect makeplacing and tracking orders easy. For personalcontact, our fully trained staff of customer servicerepresentatives are only a phone call away at1-800-233-3900.Parker Sealing Solutions is a completeprogram, not just product.PackagingTraditional non-fluoroelastomer Clipper Oil Seals arepackaged in the bluebox.FluoroelastomerClipper Oil Seals arepackaged in the brownbox.Parker Oil Seals arepackaged in the goldbox.03/28/06 Worldwide and local support is just a phone call away. Your local Parker sales representative provides a single point of contact for local sealing support. Our established worldwide network of over 300 distributor and service center locations, including global sales and engineering, means you can always get quality products when and where you need them. It also means that sound advice from Parker sealing experts is never far away.Parker Oil Seals with ParKote bore sealantIntroduction1-8 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAApplicationsRotary Seals for Steel & Paper IndustryRotary Seals for Industrial EquipmentBearing Isolators for IndustryRotary Seals for Heavy EquipmentRotary Seals for Power GenerationPTFE Seals for High Performance Backup Rolls Mill Stands Felt Rolls King & QueenRolls Reducers Gearboxes Pumps Motors Bearings ANSI Pumps Electric Motors Split Pillow Blocks Turbines Gearboxes03/28/06 Mining Construction HD Reducers Turbines Blowers Pumps Motors Bearings Centrifuges Pumps Gearboxes Mixers Instrumentation Semiconductor Medical Equipment1IntroductionCatalog EPS 5350/USA1-9 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comSealing SystemsThe completeness of Parkers rotary sealoffering allows customers to improve performanceSystem incorporating lip sealand a shaft repair sleeveSystem incorporating two seals back-to-back with grease purge for improvedcontaminant exclusion and oil retentionStandard lip seal with internal DS slingerto protect lip from lubricant surge03/28/06System incorporating SSWslinger andProTech bearing isolator for optimalexclusion on vertical up applicationSystem incorporating two lip sealswith grease purge and SSW slinger formaximum exclusionElastomeric lip seal for oil retentionwith PTFE lip seal for exclusionby utilizing a sealing system. This approach uses multiple sealing products when require-ments exceed the capability of a single seal. Some of the more common systems are pictured below.1Introduction1-10 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAV-Seal used to protect primary oilseal from excessive contaminationMulti-lip FlexiCase design for sealinghigh pressure and excluding dust03/28/06Opposed dual spring-loaded lips forseparation of two fluidsFlexiCase in gas turbine engine sump for high speed, 15,000 sfpmFlexiCase in refrigerant recovery system, 300 psiFlexiLip in air conditioning compressor260 sfpm, 20 - 300 psiFlexiSeal used in tank cleanerslow speed, 1000 psi12Catalog EPS 5350/USA2-1 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comEEnnggii nneee err ii nnggContentsRotary Shaft SealsWhat Is the Purpose of a Seal? . . 2-1History of Shaft Seals. . . . . . . . . . 2-2How Do They Work?. . . . . . . . . . . 2-3Seal Components . . . . . . . . . . . . . 2-4Lubricant Considerations . . . . . . . 2-6Shaft Considerations . . . . . . . . . . 2-6Testing for Machine Lead . . . . . . . 2-7Shaft Tolerances. . . . . . . . . . . . . . 2-8Underlip Operating Temperature. . 2-8Seal Torque . . . . . . . . . . . . . . . . . 2-9Internal Pressure . . . . . . . . . . . . . 2-10Shaft Speed . . . . . . . . . . . . . . . . . 2-10Housing/Bore Considerations . . . . 2-11Shaft to Bore Misalignment. . . . . . 2-11Shaft Runout . . . . . . . . . . . . . . . . 2-12Shaft Seal Summary. . . . . . . . . . . 2-12Shaft Seal Installation. . . . . . . . . . 2-12Handling and Storage . . . . . . . . . . 2-14PTFE Shaft SealsHow Do I Choose the Right Profilefor My Application? . . . . . . . . . . . . 2-15Spring Designs . . . . . . . . . . . . . . . 2-16Lip Shapes . . . . . . . . . . . . . . . . . . 2-20Shaft Considerations . . . . . . . . . . 2-21Housing/Bore Considerations . . . . 2-22Pressure and Shaft Velocity . . . . . 2-23Lubrication . . . . . . . . . . . . . . . . . . 2-24Rotary PTFE Product Choice . . . . 2-24Shaft Misalignment and Runout . . 2-25Rotary PTFE SealConsiderations . . . . . . . . . . . . . . . 2-26Alternate HousingConfigurations . . . . . . . . . . . . . . . 2-26Bearing IsolatorsGeneral Theory of Operation . . . . 2-27Testing and Validation . . . . . . . 2-30Rotary Shaft SealsWhat Is the Purpose of a Seal?Today there is a wide selection of designs available foruse in rotary applications. They range from the traditionalsingle and double lip elastomeric configurations to PTFE-based designs. Even more complex designs incorporatemultiple lips, differing materials and hybrid labyrinth designs.The purpose of this reference guide is to assist engineersand maintenance professionals in selecting the best designfor a specific application based on service life requirementsand cost objectives.One of the most common purposes of a lip seal is toprotect the bearing that is used to support a shaft in a rotatingapplication. Retaining the bearing lubricant and keeping itclean ensures maximum bearing life and increases the overallservice life of the equipment. Such applications includeautomotive wheels, electric motors, pumps, gearboxes andlarge rolls used in steel and paper manufacturing.Radial lip seals are used throughout industries in a varietyof other applications under a wide range of operatingconditions. These conditions can vary from high-speed shaftrotation with light oil mist to low speed reciprocating shaft inmuddy environments. Radial lip seals can be found sealinglube oil in high speed crankshaft applications for gasoline anddiesel engines that operate from the tropics to the arctic, insubmarines, oil tankers, spacecraft, windmills, steel mills,paper mills, refineries, farm tractors, appliances andautomobiles. In fact, they can be found in anything that has arotating shaft.03/28/06Parker rotary shaft seals retain lubricationand exclude contaminants even in the mostextreme environments.Engineering2-2 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAIn rotating applications, a seal can also impactthe service life of indirect components such asmechanical seals, couplings, pulleys or other in-line coupled equipment. If a seal allows the systemlubricant to run below safe levels or allows foreignmaterial to enter the bearing cavity, the bearing willsoon begin to show signs of failure. As the bearingfails, vibration from excessive shaft runout will betransferred to all other in-line components and willshorten their service life as well.The advantages of radial lip seals include: lowcost, small space requirements, easy installationand an ability to seal a wide variety of applications.In review, the primary purpose of the radial lipseal is to retain lubricants within a sump or cavity.The secondary purpose is to excludecontaminants from the system lubricant. Lip sealsare also used to separate two different fluids,retain internal pressure or exclude an externalpressure.History of Shaft SealsThe earliest seals were rags and pieces ofleather straps tied at the end of cart wheel axles toretain the animal fat or olive oil used at that timefor lubrication. This slowly evolved to morecomplex sealing systems and lubricants, such asgrease made with olive oil and lime.The Industrial Revolution accelerated sealinginnovations with bores in the wheel hubs to holdpackings and ropes to seal rotating shafts. Highershaft speeds increased operating temperaturesand the development of thinner lubricantsdemanded constant improvements in seal design.This brought along better braided ropes made byspecialists using different impregnations such aswaxes and pitch.In the 1930s, seals with beveled leatherwashers crimped in metal cases were produced.These assembled seals did not requireadjustments and were easy to install and fit inmuch less space than the packings and stuffingboxes previously used. Leather inserts with tallerflexible lips were also used because they werebetter able to follow the wobble of the shafts.Springs were added to the leather lip seal inthe 1940s. Leather was treated to reduce theseepage of lubricants through the sealingelements, but even with different coatings andimpregnations, leather could only work slightlyabove the boiling point of water, so a bettermaterial was needed. The new material becamesynthetic rubber and was introduced as a lipmaterial during World War II. During the war,copper coating and later chemical coats wereused to bond the rubber to metal washers thatwere assembled in metal cases.In the 1960s, the bonding became reliableenough that rubber lips were molded directly to theouter case. This eliminated possible leakage frombetween the assembled components. This wasdue to the components becoming loose fromcompression set of the rubber or distortion of thecomponents from assembly into the bore. Leatheralso remained a common lip material throughoutthe 1970s.Today, assembled seals made with leather orrubber are no longer recommended because oftheir high cost, internal leakage, and lack ofdimensional control. Most manufacturers haveconverted small diameter seals to the bondeddesign; however, the need to use advanced materials such as thermoplastics (primarily PTFE)that can be difficult to bond to a metal case may still require an assembled case design. Largediameter seals have been much slower to moveaway from the antiquated assembled design, soextra care should be used when sourcing sealsfor large diameter applications.03/28/06Early seals were made from leathercrimped in metal cases.2EngineeringCatalog EPS 5350/USA2-3 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comHow Do They Work?Rotary shaft seals work by squeezing andmaintaining the lubricant in a thin layer betweenthe lip and shaft. Sealing is further aided by thehydrodynamic action caused by the rotating shaft,which creates a slight pumping action.The second function of the seal is to excludeoutboard material that can contaminate thesystem lubricant or directly damage the bearing.The type of contamination the seal will need toexclude is dependent on the application. The morecommon types are moisture and water, and drymaterials including dust, sand, dirt or particulatessuch as those generated by manufacturingprocesses.Figure 2-1. Rotary Shaft Seal at WorkThe seals ability to retain the system lubricantand exclude contaminants plays a key role in theservice life of equipment components such asbearings, gears and any other component thatrelies on the system lubricant. The seal can have adramatic impact on the service life of the systemlubricant by retaining the optimal level, reducingexposure to excessive frictional heat andexcluding foreign matter.Typical petroleum oil has a useful life of thirtyyears at 86 F (30 C) if it is not contaminated withwater or particulate matter, but the same oil has alife of only a month at 212 F (100 C). As little as0.002% water in oil lubrication can reduce ballbearing life by 50%, primarily through hydrogenembrittlement. Solid particles cause more rapiddamage to the bearing race through high-localizedstresses and increased frictional heat.ContaminantsSeal Lip LubricantHydrodynamic Pumping Action03/28/06 Rotary shaft seals provide protection by performing two critical functions. In most applications the primary function of the seal is to retain the bearing or system lubricant. There are thousands of different types of lubricants available today, but in general bearings are either oil or grease lubricated. The sliding contact between the seal lip and the shaft will generate friction, increasing the contact temperature beyond the temperature caused by the bearings and other sources. Heat accelerates the breakdown of the oil and starts forming a varnish on the hot spots. Over time, the varnish changes to carbon and builds in thickness as the surrounding oil loses its lubricity. How quickly this happens is dependent on temperature. The deposit can lift and abrade the lip, causing leakage. The time to reach each stage is cut in half for each 18 F (10 C) increase in temperature. The heat also accelerates the cure of the rubber, especially at the contact surface between the seal lip and the rotating shaft. Eventually the lip surface hardens, small cracks form and the surrounding rubber stiffens. The cracks get larger and the lip stiffer,until it can no longer follow the movement of the shaft or seal. In order to maximize seal life, it is critical to minimize the amount of frictional heat of the application. The amount of frictional heat that is generated is a combination of many operating parameters.Shaft surface, internal pressure, operating speed, lubricant type, lubricant level, lip geometry and lip material are just a few of the conditions that need to be considered. It is important to note that these conditions are very interactive. For example, an increase in shaft speed will increase the sump temperature. If not vented, the temperature rise will increase the pressure inside the housing. The internal pressure will push on the seal lip and create additional force between the seal lip and the shaft. In turn, the operating temperature under the seal lip will see a significant rise in temperature and can cause premature seal failure within hours.2Engineering2-4 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAIt is easy to see why an understanding ofrotating shaft seals is critical when trying to reducethe mean time between failure of rotatingequipment. To better understand how rotary lipseals work, knowledge of basic seal componentsis needed.Seal ComponentsTypical rotary shaft seal components include arigid outer component and a flexible inner lip (seeFigure 2-2). The seal lip can be springless orspring-loaded.Figure 2-2. Seal ComponentsThe outer rigid material can range from carbonsteel, aluminum and stainless steel to anonmetallic composite as pictured above. Thepurpose of the outer component is to position andretain the seal in the housing. The seals outercomponent must also be able to maintain a leak-free fit between the seal and the housing.The seal element is attached to the outer rigidmaterial by bonding it as it is cured in a moldingpress or mechanically crimping a cured elementbetween metal components. Designs that use highperformance composite materials for the rigidouter section provide the advantages of a one-piece molded construction. One-piece moldeddesigns and bonded designs should be usedwhenever possible. Assembled designs (small orlarge diameter) are easily damaged duringhandling and installation, causing the assembledcomponents to loosen. This creates leak pathsbetween the various components.The sealing lip configuration will vary based onthe type of service, speed, pressure and dynamicrunout for which the seal is designed. The sealgeometry may also include hydrodynamic pumpingfeatures which are normally molded into the lipelement on its air side. Common hydrodynamicpatterns are triangular and helical. They functionby pumping oil that has passed by the primary lipback under the lip to reduce leakage, extendingseal life. Refer to Section 4 for lip profile options.The oil side of the seal lip has an angle in therange of 35 to 55 degrees. The air side has amuch shallower angle and is typically 15 to30 degrees. These angles determine the contactfootprint of the lip on the shaft. Incorrect angleswill form a footprint that cannot maintain a sealwith the shaft and explains why heavy leakageoccurs if a lip seal is installed backwards, or withthe steep lip angle facing away from the oil side.Seal Outer DiameterLubricantSideFlexThicknessGarterSpringHeelSectionAir SideSurfaceContactPointR ValueLip InnerDiameterHeadThicknessScraperAngleBarrelAngle03/28/06 The outside diameter of the seal is larger than the seal housing to create a press fit. The actual seal diameter will depend on the size and material of the seal, the size and material of the housing and expected internal pressure and temperature. For general industry standards on OD press fit, see Tables 6-2 and 6-3 on Page 6-3.2EngineeringCatalog EPS 5350/USA2-5 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comThis also means that the primary function ofsingle spring-loaded designs is dependent on theinstallation direction. While the seal will performboth retention and exclusion functions, they arenot performed equally.If the primary function is retention, the sealshould be installed with the steep lip angle facingtowards the lubricant. This is normally the open-faced side. If the primary function of the seal is toexclude, the steep angle needs to face toward thecontaminant (see Figure 2-3).Figure 2-3. Installations Facing Lubricant andContaminantIf both retention and exclusion are critical andthe level of contaminants is heavy, one seal shouldbe used to retain the lubricant, and exclusioncapacity should be added using another lip seal,auxiliary excluders or by upgrading to a bearingisolator (see Page 2-27).The purpose of the spring is to provide aconstant, uniform load of the lip on the shaft for thelife of the seal. The spring keeps the seal lip incontact with the shaft during higher shaft speedsand also overcomes compression set and wear ofthe lip material. Compression set of the lipmaterial is normal as it is subjected to thermalcycles during operation.Several spring types are used to energize thelip. The most common is a wound spring, oftenreferred to as a garter spring. Finger springs areanother option, although their loading is typicallyless uniform and they can be subject to severedistortion prior to or during installation, leading toareas of the lip that are not properly loaded. Otherspring types used are cantilever, canted-coil andhelical which are normally used in PTFE designs.In order for the spring to maintain the proper loadover the life of the seal, the spring must becompatible with the fluids and the temperature ofthe application.The dimensional relationship between thecenter of the spring and the lip contact point iscalled the R value. The leading edge of the lipshould be toward the oil side, with the centerlineof the spring slightly toward the air side. If thecenterline of the spring is too far toward the airside (too positive R value) it will put too much ofthe lip (wide footprint) in contact with the shaft andcause excessive wear. A spring position that is tooclose to the lip contact point (negative R value)can cause the lip to become unstable or roll anddump the spring.A spring-energized lip is required for positiveoil retention, but not typically for grease retention (see Figure 2-4).Figure 2-4. Oil and Grease Sealsthe sealing system. There are several key The rotary shaft seal is only one component inoperating parameters that can work in unison tooptimize seal life, or conversely, if misapplied,can reduce seal life to a few operational hours. 03/28/06l a e S e s a e r G l a e S l i O2Engineering2-6 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USALubricant ConsiderationsFigure 2-5. Sealing SystemThe contact lip is designed to run on a thin filmof oil. Without the oil film, the seal lip will rundirectly on the rotating shaft and generateexcessive friction and fail within hours. Thelubricant selected needs to remain viable over theexpected service life. If the underlip temperatureexceeds the lubricant rating, carbonization of theoil will occur.Abrasive carbonized oil particles will build upat the seal lip and accelerate lip and shaft wear. Asthe oil film becomes less than optimal, the lipfriction increases, as does lip wear.When selecting a lubricant keep the followingin mind:1. Do temperature limits of the lubricant matchthe underlip operating temperature of the seal?2. Are the base oil and additives compatiblewith the lip material?3. Does the oil level provide adequatelubrication and cooling at the seal lip?Shaft ConsiderationsHousingLubricantShaft SpeedPressure18 Ra18 Ra18 RaSurface Finishes A proper shaft finish provides small pockets to hold the needed oil film between the lip and shaft, preventing direct contact that would otherwise cause friction and wear as the shaft rotates. The shaft surface must also be smooth enough to avoid peaks that are large enough to break through the lubrication film. The optimal surface for elastomeric shaft seals is a plunge ground finish of 8 to 17 in Ra (0.20 to 0.43 m Ra) (0.010" [0.25 mm] cutoff) with a lead angle below 0.05 degrees. (See Table 2-5 on Page 2-21 for shaft finish requirements for PTFE seals.) Recent studies show that the Ra measurement alone is insufficient to quantify a proper surface. The surfaces below have the same Ra finish, but the impact on seal performance will vary. Two additional requirements are needed: Rz (the average peak to valley height) of 65 to 115 in (1.65 to 2.90 m), and RPM of 20 to 50 in (0.5 to 1.25 m), the average peak to mean height. For additional information, refer to Rubber Manufacturers Association Technical Bulletin OS-1-1.03/28/062EngineeringCatalog EPS 5350/USA2-7 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comWhen a shaft is turned to size, a continuousspiral groove is imparted on the shaft as thecutting bit traverses the shaft. This is called shaftlead.If not removed by plunge grinding or othermethods, the groove will act as an auger when theshaft rotates. The underlying groove will eitherpump oil past the seal lip or contaminants into thebearing housing, depending on the direction of theshaft rotation.If a shaft is going to be plated, the machinelead must still be removed prior to the platingprocess.Testing for Machine LeadWhen lead is suspect and there is a need forverification in the field, the following field test canbe performed:1. Mount the shaft in a chuck and verify theshaft is level.2. Lightly coat the shaft with silicone oil with aviscosity of 5 to 10 cps.3. Drape a thread (unwaxed quilting thread0.009 inches or 0.23 mm dia.) weighted with aone-ounce (30 g) weight around the shaft and tiethe ends together so it is long enough to contactabout 2/3 of the circumference of the shaft with theweight hanging. Position the thread so that theknot is not touching the shaft.4. Rotate the shaft at slow speed, 60 RPM.5. Place thread at both ends as well as centerof shaft and observe for axial movement of thethread under BOTH CW and CCW rotation. Movement of the thread in oppositedirections, CW versus CCW rotation,indicates lead is present. If the thread moves in the same directionunder both CW and CCW rotation, verifythat the shaft is level. If the thread remains stationary whenchecking the ends and center of shaftunder both CW and CCW rotation, significantlead is not present.Figure 2-6. Shaft Lead TestingPlease note that this method does notguarantee the absence of lead as some patternsmay go undetected using the string test. However,this simple test has been very successful indetecting if a significant lead is present.The preferred material for the shaft-sealingsurface is carbon steel (SAE 1035 or 1045) with aminimum hardness of Rockwell C30 (30 Rc). Whenheavy amounts of abrasive contamination arepresent, abrasive additives are used in the lipcompound or high-pressure seal designs are goingto be used, a minimum shaft hardness of 45 Rc isrecommended to resist excessive shaft grooving.Softer materials such as bronze, aluminum orplastic will experience heavy wear (grooving), and should be avoided.Shaft Lead03/28/062Engineering2-8 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAShaft TolerancesShaft diameters should be held to thetolerances specified below:The leading edge of the shaft should have aburr-free chamfer to ease installation bypreventing lip roll-back, spring dumping anddamage (nicks or cuts) to the seal lip. Both ends ofthe chamfer should be free of sharp edges.Figure 2-7. Shaft ProfileSpecial precautions should be taken whenreplacing a seal over a used shaft because it iscommon for shafts to become grooved duringservice. Grooving is normally caused by eithercarbonized oil or an abrasive foreign mattergetting trapped between the lip and the shaft.Over time, deep grooves can form.Replacement seals should never be installedover a grooved shaft. Dressing the shaft withemery cloth is not recommended because it isextremely difficult to obtain an optimal finish andlead will normally be imparted. If the shaft is worn,it should either be re-ground or fitted with a shaftrepair sleeve. See Section 7 for shaft repair options.Underlip Operating TemperatureWhen selecting a seal design, lip material andsystem lubricant, the operating temperature underthe seal lip should be used as the upper limitrather than using the sump temperature.Underlip temperature can exceed sumptemperature by 60 F (33 C) or more, dependenton shaft diameter, shaft speed, fluid type andTable 2-1. Shaft Tolerance for Inch/FractionalShaft Diameter ToleranceUp to 4.000" .003"4.001 6.000" .004"6.001 10.000" .005"Over 10.000" .006"Table 2-2. Shaft Tolerance for Metric*Shaft Diameter ToleranceUp to 10 mm +0 to -.09 mmOver 10 18 +0 to -.11 mmOver 18 30 +0 to -.13 mmOver 30 50 +0 to -.16 mmOver 50 80 +0 to -.19 mmOver 80 120 +0 to -.22 mmOver 120 180 +0 to -.25 mmOver 180 250 +0 to -.29 mmOver 250 315 +0 to -.32 mmOver 315 400 +0 to -.36 mmOver 400 500 +0 to -.40 mm*ISO Standard 286-2, h11Shaft GroovingSpring dumping can occur during seal installation when the lip rolls back on itself, causing it to fall out of the spring pocket. Heavy shock loads that can occur when installing a metal cased seal using a direct blow from a metallic driving tool can also force the spring out of the spring pocket and is also referred to as spring dumping. level. The increased temperature can exceed the limits of both the lip material and lubricant that is selected based on the sump temperature alone.Table 2-2a Min. Chamfer LengthEnglish MetricShaft Dia Length Shaft Dia LengthUp To And "w" Up To And "w"Including (inch) Including (mm)0.375 0.051 10 1.30.750 0.068 20 2.01.250 0.085 30 2.21.500 0.102 40 2.62.000 0.119 50 3.02.750 0.136 70 3.53.750 0.153 95 3.95.000 0.188 130 4.89.000 0.239 240 6.1+18.000 0.375 480 10.030At 30wSee Table 2-2a for chamfer length2EngineeringCatalog EPS 5350/USA2-9 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comOther operating parameters such as a roughshaft finish or internal pressure will drive theunderlip temperature even higher. As a generalrule, the F increase in underlip temperatureabove the sump temperature can be estimated asthe square root of the shaft speed in feet perminute. (Replace the feet per minute units with F.)This would be 55 F (30 C) for a shaft running at3000 fpm (15 m/s).Figure 2-8. Example Shaft ConditionsSeal TorqueThe underlip temperature increase is due tothe friction between the shaft and seal lip. Torqueis the frictional force the shaft must overcome torotate in the seal. The energy consumption of theseal can be determined when the torque and shaftspeed are known. Different seal designs, rubbercompounds, fluids, fluid levels, temperatures, shafttextures, pressures and time in service each affectfriction, so there is no exact calculation to predicttorque. However, the following can give an approx-imate value for elastomer shaft seals. When thetorque value is critical for the application,testing should be performed.Torque from a dry running seal is 2 to 3 timesthe above.For example: Torque is about 90 in-ounces fora three-inch shaft rotating at 3600 revolutions perminute in 250 F SAE 30 weight oil to the shaftcenter. The energy in kilowatts the seal uses is7.395 x 10 -7x torque x revolutions per minute. Inthis case, 0.24 kW.Bearing isolators are an excellent choice when low torque is required because they add virtually no torque to the system.Shaft Sealin fpmIncrease UnderlipTemperature=3000 fpm 55 F =80 90 100 110 120 130 1401501401301201101009080300280260240220200180160180 200 220 240 260 280 300320Sump Temperature CSump Temperature FUnderlipTemperatureFUnderlipTemperatureC5000 Rpm4000 Rpm3000 Rpm2000 Rpm1000 Rpm0 Rpm03/28/06Seal Torquein-ounces 0.65 Shaft Dia.in inches2s Rpm1/3s = As sump temperatures increase, the differ-ence between sump and lip temperature decreases. Figure 2-8 shows the relationship of shaft diameter, shaft speed and sump temperature and the impact they have on the temperature at the contact point of the seal lip and the shaft (underlip temperature). An easier but more crude estimate is 20 F (6.7 C) higher than the sump for each 1,000 RPM of shaft speed for sump temperatures about 75 to 210 F (24 to 99 C). 2Engineering2-10 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAInternal PressureMost elastomeric lip seals are designed to workin vented applications with zero internal pressurebut will provide satisfactory service with pressuresup to 3 psi (0.20 bar). Higher pressure will forcethe lip against the shaft and cause excessivefriction. Severe pressure will distort and force theairside of the lip to contact the shaft and cancause massive failure within hours of operation.See Figure 2-9 below. Excessive pressure canalso push the seal out of the housing.Figure 2-9. Internal PressureParker offers several designs for applicationswhere high internal pressure cannot be avoided.Elastomeric designs include MP, HP, NTC, TDN,and depending on design, can handle service upto 300 psi (20 bar). Refer to Pages 5-13 and 6-11.Most PTFE designs can handle pressure, some up to 10,000 psi (690 bar). See Tables 9-4,10-4 and 11-4.Shaft SpeedMost seal manufacturers rate the speed limitusing surface feet per minute (or meters persecond). This is a measurement of how manysurface feet (meters) pass a given point at the seallip per minute (second) in time. Since this methodconsiders the shaft diameter in addition to speed, itis a better service indicator than RPM alone.The formulas below can be used to determinethe fpm (feet per minute) or m/s (meters persecond) for metric applications.InchMetricA typical seal design in NBR material canoperate up to 3,000 fpm (15 m/s) assuming allother operating parameters are reasonable. If anyof the other operating conditions are excessive,seal designs and material upgrades are availableto improve performance. Parker FKM and PTFEseals can be used for applications approaching6,000 fpm (30 m/s) and ProTech bearing isolatorsfor even higher speeds.03/28/06Shaft Diameter RPM s 0.262 fpm = sShaft Diameter (mm) RPM s 0.000523 m/s = s Shaft seals operate in a wide range of speeds. When shaft speeds increase, so does underlip temperature, wear and internal pressure, if oil sumps are not vented. To assure optimal performance, select the proper seal design and material to accommodate for these factors.2EngineeringCatalog EPS 5350/USA2-11 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comHousing / Bore ConsiderationsTypical radial shaft seals are pressed into thebore to assure proper OD sealing and sealretention in the housing. The most commonly usedmaterials for seal housings are steel and cast iron.Care must be taken when softer materials such asaluminum, bronze or plastics are used for thehousing material. Aluminum has a thermalexpansion rate almost double that of steel. Steelcase designs can lose the required press fit in analuminum housing when they go through thermalcycles.A seal with an aluminum, composite or rubbercovered OD should be used for aluminum housings.These materials help maintain the press fit in the housing during thermal cycles and reduce the possibility of galvanic corrosion. Plastic housings can also expand at rates that can create problemsif a metal OD seal is used. The following chart shows typical values ofthermal expansion for common metals in inch/inch/F.Fiber reinforced and rubber OD seals are moreforgiving so their bore tolerance can be greaterthan for metal OD seals. Aluminum bores aretypically smaller than steel bores for metal ODseals to compensate for some of the difference inthermal expansion. A finish range of 40 to 100 inRa (1.0 to 2.5 m Ra) is recommended for servicepressures up to 3 psi (0.20 bar). If the fluid is thick,such as a grease, a 125 in Ra (3.17 m Ra) finishwould be acceptable with no system pressure.The finish on aluminum bores is more sensitiveand must be maintained to keep seals fromspinning in the bore and should not be smootherthan 60 in Ra (1.5 m Ra).A lead-in chamfer is highly recommended forall seal housings. The chamfer aligns the sealduring installation and helps prevent the seal fromcocking. Both corners of the chamfer should befree of burrs and sharp edges.Figure 2-10. Housing ProfileShaft to Bore Misalignment (STBM)When the center of the shaft rotation is not thesame as the center of the bore, the shaft pushesagainst the lip on one side of the seal greater thanthe other. This can cause the lip to wear rapidly inone place and have inadequate contact on theopposite side.Figure 2-11. STBMTable 2-3. Typical Values of Thermal ExpansionItem ValueAluminum 0.000013Brass 0.000011Carbon Steel 0.0000058Cast Iron 0.0000059Stainless Steel 0.00001003/28/06Bore Chamfer15 to 300.060 to 0.090"(1.5 to 2.2 mm)Bore Centerline Shaft CenterlineSeal HousingCavity Diameter(Bore)Misalignment EccentricityWith eccentricity, onlystatic radial deflection isimposed on the seal.2Engineering2-12 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAShaft RunoutWhen the shaft does not rotate around itscenter, it wobbles. This condition is called runout.The seal lip has to move back and forth tomaintain contact. The life of a seal is shortened asthe runout is increased, and when the runoutexceeds the capability of the lip, it will leak.Parker offers seals for misalignment conditions.See Pages 5-15 and 6-17.Figure 2-12. Shaft RunoutShaft Seal SummaryIn conclusion, because the seal is only onecomponent of the sealing system, all the followingoperating factors need to be considered foroptimal seal life:Lubrication: A seal is designed to run on a filmof oil. Without the film of oil, the sealing lip willharden and crack due to the heat generated byexcessive friction. The lubricant must also becompatible with underlip temperatures to avoid thebuildup of abrasive, carbonized particles at the seallip.Shaft Finish: A shaft finish that is too smoothwill cause a stick slip flutter that will let the fluidescape under the lip and cause excessive heatthat will harden the lip. Excessive roughness willpenetrate the lubricant film, cause leakage andaccelerate lip wear. Maintaining the desiredsurface finish is critical for maximizing the servicelife of any contact rotary lip seal.Shaft to Bore Eccentricity: When the center ofthe shaft rotation is not the same as the center ofthe bore, the shaft pushes against the lip on oneside of the seal greater than the other. This cancause the lip to wear rapidly in one place and haveinadequate contact on the opposite side.Dynamic Shaft Runout: When the shaft doesnot rotate around its own center, the lip has tomove back and forth to follow it. In excess, the lipwill be unable to maintain contact as the shaftrotates, causing leakage.Pressure: Excessive pressure will force the lipagainst the shaft and cause excessive frictionalheat and wear.Bore: A bore finish that is too coarse cancause a leak path by itself. If it has burrs or othersharp edges, they can scar the metal diameterduring assembly, causing a leak path on the sealOD.Speed: Shaft speed causes the underliptemperature to increase in addition to elevating theoverall sump temperature. Over time, the heat willharden the elastomeric lip and reduce the sealsability to maintain positive contact with the entirecircumference of the shaft.Operating Temperature: Controlling thetemperature of the sealing system is key tomaximizing seal life. The relationship betweenspeed, sump temperature, underlip temperature,pressure and shaft finish need to be consideredsince these operating parameters are interactiveand will determine the service life of both the lipmaterial and system lubricant.Shaft Seal Installation1. Prior to installation the seal should beexamined to ensure that it is clean, undamagedand the correct seal for the application.2. Verify spring is present for spring-loadedseal designs.3. Prelubricate the seal lip with a system-compatible lubricant. It is preferable to use thesystem lubricant.4. For seals with a rubber outside diameter,lightly lubricate seal OD with a system compatiblelubricant. DO NOT LUBRICATE THE OD OF ACLIPPER OIL SEAL THAT HAS A COMPOSITE OD.Bore CenterlineShaft RunoutEnvelopeShaft CenterlineOrbits around theaxis of rotationShaft Axis ofRotationShaft Runout EccentricityShaft GeometricCenterlineIn this case, cyclical radial deflection due to runout issuperimposed on static radial deflection due to eccentricity.03/28/0622EngineeringCatalog EPS 5350/USA2-13 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.com5. Verify the desired lip direction for theapplication (lip toward oil for best retention).6. Examine the leading edge of the shaft.Shaft should be properly chamfered and free ofnicks and burrs that could cut or nick the seal lip.7. Examine the leading edge of the housing.The seal bore should be chamfered and free ofnicks and burrs that could gouge the seal outsidediameter or make the seal difficult to install into theseal housing.8. Examine the shaft where the lip will makecontact. This surface must be free of grooves fromprior service. If shaft is damaged or worn in thisarea, dress shaft for proper finish or install a QuickSleeve or wear sleeve. If using a Quick Sleeve, anoversized seal is not required. If using a standardwear sleeve, the replacement seal must have aninside diameter that is designed to be used withthe wear sleeves outside diameter.9. If the seal lip must pass over keyways orsplines on the shaft, use an installation sleeve toprotect the seal lips as they pass over these areas.If an installation sleeve is not available, wrapmasking tape around the shaft to form a protectivebarrier.10. Slide the seal over the shaft to the sealhousing. With finger pressure, start seal intohousing with a slight rotating motion until seal hasa light press fit in the housing. Be sure seal issquare or perpendicular to the shaft. If the seal iscrooked or cocked, continuing with installation willdamage the seal.11. Position the installation tool and drive theseal into the housing until it is flush with thehousing or recessed into the bore the properdistance. Please note that a screwdriver, punch orhammer should not be used to install the seal.Refer to the diagrams at right for recommendedinstallation tools.12. When using a metal driver to install metalclad seals, extra care is needed to be sure theshock load does not dislodge the spring.13. If the seal is cocked in the housing, removeseal and start over using a new seal. Attempts tosquare the seal in the housing using direct blowswill damage the seal.14. Inspect the seal to be sure it is straight andflush. Examine the face of the seal for damage. Ifit is dented from installation, the lip will bedeflected and will normally cause prematurefailure.Counter Bore Installation Flush MountTool bottoms out against machined face ofhousing to position seal.Counter Bore InstallationSeal is positioned square by seating againstcounter bore.03/28/06Engineering2-14 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USARecessed InstallationTool bottoms out against end of shaft toposition seal in the housing.Installation SleeveUse to install seal over keyways and splines.Handling and Storage1. Care should be taken when storing rotaryshaft lip seals to ensure optimal performance.2. Seals should be stored in a cool, dry areabelow 86 F (30 C) with an average relativehumidity of 40 to 70%.3. Rotating stock is important. If inventory isold, seals should be used on a first in, first outbasis. Based on the relative low cost of a lip sealcompared to the expense associated with a failedpiece of equipment, a good practice is to discardaged inventory since old seals may havedeteriorated lip materials.4. Seals should be stored away from direct orreflected sunlight and electrical equipment toavoid UV and ozone aging of the lip material.5. Avoid storing seals in damp areas or wherehigh humidity is present. Excessive humidity willdeteriorate some seal element materials. Metalcases and springs will also rust and corrode ifexposed to high levels of moisture or humidity.6. Seals should not be exposed to radiation.7. Keep seals stored in proper packaging. Donot store unpackaged seals on the shelf.8. Do not use wire or string to tag a seal. Wirecan easily cut the seal lip. Wire or string can alsodeform the lip beyond the point of recovery andcan lead to leakage at start-up.9. Do not store seals on hooks, nails orpegboard. Over time the weight of the seal restingon the hook will deform the lip beyond recovery.10. Avoid storing seals where high levels offumes are present. Depending on the chemicaland concentration, it can chemically interact withthe lip material.03/28/062EngineeringCatalog EPS 5350/USA2-15 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comPTFE Shaft SealsHow Do I Choose the Right Profile for MyApplication?Parkers PTFE product line includes bothstandard designs for the most commonapplications and custom designs that ourengineers can help you develop.For the long term, we suggest that youfamiliarize yourself with the design elements in thisEngineering section that are critical whenchoosing a FlexiLip, FlexiCase or FlexiSeal.For quick reference and ease of sortingthrough the many standard designs, we haveprovided simple decision trees and placed themthroughout this design guide. If it becomesapparent that you need a custom design to meetyour unique needs, or if you just want us to confirmthe standard seal choice youve made, pleasecontact Parkers PTFE Engineering team at801-972-3000.Parker designs and manufactures a completeline of PTFE seals for both reciprocating androtary applications. This guide focuses on sealsfor rotary applications. For reciprocatingapplications please refer to publication EPS 5340PTFE Lip Seal Design Guide.PTFE lip seals are commonly used as anupgrade over elastomeric lip seals whenconditions are severe. Common reasons forupgrading to a PTFE material include chemicalcompatibility, poor lubrication at the lip, highpressure, high speed or high temperature.For rotary applications, Parker offers threeprimary design groups: FlexiLip, FlexiCase andFlexiSeal.FlexiLip seals are available in the above basicprofiles. Excluder lips and internal metal stabilizerbands can be added to each profile depending onapplication requirements. The main difference isthe shape of the primary lip. Additional optionsare available for the lip and O-ring material foradded design flexibility.LF = Mandrel Formed LipLE = Elf Toe LipLG = Lip With Garter SpringLM = Machined LipLD = Dual LipFlexiLip seals are intended for continuousrunning rotary shafts under various operatingconditions. An O-ring is used on the OD forpositive static sealing and proper bore retention. Typical operating limits are up to 6,000 sfpm,150 psi and 450 F (30 m/s, 10 bar and 232 C).See Table 9-4 on Page 9-10 for specific limits.CF = Mandrel Formed LipCM= Machined Lip FormCE = Elf Toe LipCD = Dual LipsCH = High Pressure Dual LipCG = Lip With Garter SpringFlexiSeal rotary seals are spring-energizeddesigns and are available in the basic profilesabove. Three spring options are available for eachprofile: cantilever, canted-coil and helical. Shaftspeeds are very limited (below 1,000 sfpm or5 m/s) but they can provide positive sealing to10,000 psi (690 bar). This is the preferred designfor rotating unions as well as oscillating and slowrotating shafts under high pressure conditions.LF LE LG LM LD 03/28/06CF CM CE CD CH CGFC FH FF FlexiCase designs feature PTFE lip elements encased in a metal jacket and are available in the above basic profiles. FlexiCase designs can be used in the same applications as FlexiLip profiles where more bore retention is required. Excluder lips can be added for additional exclusion capac-ity. Additional options are available for the lip and case material for added design flexibility. Typical operating limits are 6,000 sfpm, 500 psi and 450 F (30 m/s, 34 bar and 232 C).22-16 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comEngineeringCatalog EPS 5350/USASpring DesignsFlexiSeal profiles utilize threedifferent spring designs.The two elements to consider whenselecting a spring design are its loadvalue and its deflection range. Thesprings load affects the sealing ability,friction and wear rate. As the springload is increased, the lips seal tighter,with friction and wear increasingV Series CantileverC Series Canted-CoilH Series Helicalproportionately. The springs deflection range affects theseals ability to compensate for variations in gland tolerancesand for normal seal wear. Each spring size has a specificdeflection range. The available deflection increases as theseal and spring cross-section increase; this could be adeciding factor in selecting one cross-section over another.Springs with a wide deflection range should be used whensealing surfaces are nonconcentric (see Page 2-25).Figure 2-13. Spring LoadingFigure 2-14. FlexiSeal Spring EnergizersFigure 2-14 shows a relative comparison of load vs.deflection curves for the three spring types. The signifiesthe typical deflection when the seal is installed. The hatchmarks indicate the deflection range through which the sealwill function properly. Notice that H Series has a muchsmaller deflection range than both the V and the C Series.03/28/06Spring Loading ProvidesPositive Sealing ContactSpring-Loaded,Positive ContactNot Loaded,Poor ContactV SeriesC SeriesH SeriesSpring CompressionSpringLoad2EngineeringCatalog EPS 5350/USA2-17 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCantilever Springs V SeriesThe FlexiSeal Cantilever spring ismade from flat metal strip stock of300 Series stainless steel or Elgiloyas an option. The strip stock is punchedor chemically etched into a serpentinepattern and formed into a roundedV shape. It is available in either a lightor medium load spring. The mediumspring is suitable in most applications,but the light load spring can be used ifhaving low friction is more importantthan sealability. The medium springload deflection curve is depicted inFigure 2-14 on Page 2-16.The cantilever spring is intended fordynamic applications involving rotary orreciprocating motion. It can also beused in static conditions when there isneed for a higher deflection spring dueto wide gland tolerance, excessiveexpansion and contraction, or lift-offdue to high pressure.The long beam leg design puts thespring load out at the leading edge ofthe seal, creating the best load locationfor the FlexiSeal to act as a scraperwhen the optional scraper lip is selected.The geometry of the V Seriescantilever spring provides flexibility byutilizing individual tabs, separated bysmall gaps. This shape allows thespring to flex into radial and axial sealdesigns. The spring tabs can overlapon the ID and spread apart on the ODwhen the cross-section is too large forthe diameter.Table 2-4 provides the minimumdiameters for V Series springs for rodand piston seals, as well as internaland external pressure face seals. Fordiameters smaller than those listed,C or H Series spring designs arerecommended.Features V-shaped spring with moderate load vs. deflection Standard inch/fractional and MIL-G-5514 sizes Standard 300 series stainless steel springs NACE compliant Elgiloy springs available in medium springload, -450 to 600 F Scraper lip designs for abrasive medias Available as external & internal pressure face sealsRecommended Applications Reciprocating rods & pistons Rotary shafts 12.5 mm (medium) 2 Vertically falling drip water tipped up to 15 fromitsnormal positionr e t a w d e z i m o t A 3 ) l l a m s ( m m 5 . 2 > s t c e j b o d i l o S 34 Solid objects > 1 mm (grain-type) 4 Spray waterr e t a w d e t c e r i d - e s o H 5 d e t c e t o r p t s u D 5s t e j r e t a w g n o r t S 6 f o o r p - t s u D 67 Dipped in water8 Submerged in water 9k High pressure water spray (1160 to 2320 psi[80 to 160 bar]) fromspray nozzle located 4 inches(102 mm) away from seal03/28/06ProTech LW8PPrr ooTTeec chhBBeea arr i i nngg II sso oll aatt oorr ssCatalog EPS 5350/USA8-5 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comEEnnggii nneeeerr i i nnggTroubleshootingThe time to reduce or eliminate sealfailure is before it happens. In manyinstances, factors beyond the sealmanufacturers control determine theseals performance. The followingcheck lists will help identify possiblecauses of seal failure and suggestremedies.Failed Seal Resulting fromImproper FitFailed Seal Resulting fromImproper InstallationApplication Check List1. Is the correct size seal being utilized?2. Is the most suitable seal profile being utilized?3. Are the service media and the temperature compatible withthe seal material?4. Are the equipment conditions, such as the shaft to boremisalignment, shaft finish, and bore finish withinrecommended limits?5. Do any unusual equipment variables exist which mightaffect overall seal performance?Installation Check List1. Has the seal been damaged in storage or handling?2. Have the O-rings been properly lubricated prior toinstallation?3. Have the O-rings been damaged by passing over sharpkeyway, splines, threads or burrs?4. Have the O-rings rolled or twisted?5. Has the seal been installed perpendicular to the bore andshaft centerline?6. Has an adequate vent been provided to relieve all internalpressure?7. Has adequate drainage been provided to preventexcessive oil build-up over the bottom of the shaft?8. Have you verified whether a false flooded condition exists?03/28/068s r o t a l o s I g n i r a e B h c e T o r P g n i r e e n i g n ECatalog EPS 5350/USA8-6 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comTable 8-3. Troubleshooting GuideTrouble Sign Possible Source Suggested RemedySeal OD Leakage Housing bore too rough, pitted, severecorrosion, grooved, etc.Improve finish to recommended limits. (SeePage 8-13.)l a n i m o n o t e r a p m o c , r e t e m a i d e r o b e r u s a e M t i f g n i r - O D O t n e i c i f f u s n Irequired dimensions of equipment and sealrequirements.Seal OD O-ring damaged during installation Protect O-ring from all sharp burrs at leadingedge of bore. A chamfer should be used onleading edges. Lubricate O-rings prior toinstallation. (See Page 8-12.) Care shouldalso be used when storing the seal for futureusage.Seal OD O-ring damaged from chemicalincompatibilityConsult chemical compatibility chart inAppendix H. (FKM is the standard ProTechO-ring material unless specified otherwise.)Seal ID Leakage Shaft surface too rough pitted, severecorrosion, grooved, etc.Improve finish to recommended limits. (SeePage 8-13.)l a n i m o n o t e r a p m o c , r e t e m a i d t f a h s y f i r e V t i f g n i r - O D I t n e i c i f f u s n Irequired dimensions of equipment and sealrequirements. Verify nominal seal dimensionsmatch actual shaft diameter.Seal ID O-ring damaged during installation Protect O-ring from all sharp burrs at leadingedge of shaft. A chamfer should be used onleading edges. (See Page 8-12.) Care shouldalso be used when storing the seal. Toprevent cutting, protect ID O-rings from shaftkeyways, splines, etc. Use proper installationtools to prevent seal O-ring damage.Seal ID O-ring damaged from chemicalincompatibilityConsult chemical compatibility chart inAppendix H. (FKM is the standard ProTechO-ring material unless specified otherwise.)Seal Leakage from DrainPortInternal pressure present Vent housing if possible. If vented, verifybreather or pressure limiting device isfunctioning correctly. Up to 5 psi, upgradeseal design to ProTech 360.ProTech 360 only, internal pressure > 5 psi Vent housing if possible. If vented, verifybreather or pressure limiting device isfunctioning correctly.. g n i r e e n i g n E n o i t a c i l p p A r e k r a P t c a t n o C e r u l i a f l a e s l a n r e t n ISeal Leakage from betweenRotor and Statore r a s n i a r d l i o l a n r e t n i e r u s n E . l e v e l l i o r e w o L h g i h o o t l e v e l l i Oadequate. Upgrade seal design to ProTech360.Internal pressure present Vent housing if possible. If vented, verifybreather or pressure limiting device isfunctioning correctly. Up to 5 psi, upgradeseal design to ProTech 360.ProTech 360 only, internal pressure > 5 psi Vent housing if possible. If vented, verifybreather or pressure limiting device isfunctioning correctly.. g n i r e e n i g n E n o i t a c i l p p A r e k r a P t c a t n o C e r u l i a f l a e s l a n r e t n I03/28/068g n i r e e n i g n E s r o t a l o s I g n i r a e B h c e T o r PCatalog EPS 5350/USA8-7 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comDesign EngineeringThe important considerations in selecting abearing isolator are: For best oil splash retention, avoid designs thatuse simple inboard oil grooves. For long term performance, select a design thatdoes not rely on an internal seal such as anO-ring, V-ring or other internal component toachieve sealability. For best contaminant exclusion, select a sealthat is purposely designed to control laminarflow. Avoid designs that require special installationtools. The easier the seal is to install, the lesschance seal damage will occur duringinstallation. Select a material that will not introduce harmfuldusting into the bearing cavity.Further Considerations Determine what impact upgrading to a bearingisolator will have on the total cost of sealingbased on return on investment (ROI). Standardize on a material that provides thebroadest chemical compatibility throughout yourfacility. Avoid designs that are sold on features that arenot scientifically sound. Select a manufacturer that has extensiveknowledge in the science of sealing and is anindustry leader in design innovation. Ask the manufacturer for documented copies oftest results for IP55, IP56, IP66 and IP69k thathave been conducted by third parties (such asU.L.) in order to verify performance claims.Upgrading to Bearing IsolatorsThe cost of downtime in todays manufacturingenvironment has been the primary driver behindthe decision of companies to convert keyequipment such as pumps, motors, gear boxesand split pillow block bearings from a standard lipseal to a bearing isolator type seal.While the initial cost of a lip seal is much lowerthan a bearing isolator, the total cost of the sealingsystem over the life of the equipment should beevaluated as part of the decision-making process.Bearing isolators are able to extend the Mean Time Between Failure (MTBF) because true non-contactisolators will never wear out as compared tostandard lip seals that have a typical life of 3,000to 5,000 hours. Bearing isolators permanentlyexclude contaminants, which means the seal isno longer the limiting factor for the bearing approaching the L10 life rating stated by thebearing manufacturer. The primary cost savingsare a result of fewer rebuilds and less unplanneddowntime over the life of the equipment. Additionalsavings result from lower torque consumptionmeaning less energy consumption and lowermaintenance costs. Energy savings alone canoffset the costs of the upgrade. Once the decision has been made to upgradeto bearing isolators, the next step is to select abearing isolator design. The two basic designtypes are contact and non-contact. The contactdesign relies on an internal seal for excludingcontaminants while the non-contact design relieson labyrinth technology and provides zero wearingcomponents. ProTech Bearing Isolators are non-contact.The ProTech bearing isolator consists of twocomponents, a rotor and a stator.StatorAn external O-ring at theProTech stator OD maintainsa press fit in the seal housingand provides a static seal foroil retention. Because this isa static seal, it will not wearout over time.03/28/06ProTech Stator8s r o t a l o s I g n i r a e B h c e T o r P g n i r e e n i g n E8-8 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAThe O-ring press fit allows for easy sealinstallation while also providing excellent boreretention. The press fit will withstand a torque ofup to 500 in-ounces (36,000 g-cm) to eliminatespinning in the housing. The press fit has beentested in the vertical down position to ensure thestator will not walk out of the seal bore.The stator has a sophisticated series ofgrooves to retain oil splash. Before ProTech,bearing isolators relied on a single inboard groovefor oil retention. Results from independent testingby a major pump OEM showed Parkers design tobe the most effective for oil retention whencompared to various competitor designs.RotorThe secondcomponent, the rotor,uses an external O-ringto maintain a static pressfit on the shaft. Sincethe rotor spins with theshaft, it will not wear,groove or damage theshaft, so the costsassociated with havingto recondition thesealing surface of theshaft are eliminated.The wrap-around profileof the ProTech rotorprovides optimal waterexclusion.The rotor and stator are assembled at theParker factory where they are permanentlyunitized by means of a patented process. Theunitized design allows for one-piece installationand maintains a minimal clearance between therotor and stator interface for the life of the seal.This interface is the first line of defense againstcontamination. A unitized design maintains theseals integrity by keeping high-pressure waterspray, vibration or axial movement from separatingor increasing the gap between the rotor and stator.Controlling Laminar FlowProTech relies on true non-contact labyrinthseal technology. When the rotor and stator areassembled at our factory, a true non-contactlabyrinth is created. For successful waterexclusion, the labyrinth must control the laminarflow properties of the liquid entering the seal.Laminar is the flow of a liquid in an organizedlayered manner, or as the name suggestslaminates. A liquid flowing through a pipe hasvarious flow levels ranging from zero at the outerwall to a maximum along the centerline.Introduction of TurbulenceAn effective seal design must introduceturbulence into the flow. Turbulence slowsdown the rate of flow of the liquid so that gravityalone is enough to expel the liquid through theseal drain port. The left side of Figure 8-1 depictsthe faster moving laminar flow. The arrows showhow the individual water molecules line up ineven planes. The right side shows that whilelaminar flow is still present close to the seal wall,most of the fluid is a slower moving turbulent flow.The direction change, pressure differential, plus thefriction of the molecules themselves, aid in slowingthe rate of flow.Figure 8-1. Effects of TurbulenceProTech Rotor03/28/06VmVmRrTypical Laminar Flow PatternStatorRotorShaftGravityLaminar TurbulentPressure DifferentialTurbulentBuffer LayerLaminar Sublayer8g n i r e e n i g n E s r o t a l o s I g n i r a e B h c e T o r PCatalog EPS 5350/USA8-9 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comProTechs effectiveness is due to the numberof times turbulence is introduced to the flowthrough either forcing a change in direction ordropping the pressure that is pushing the fluid, byusing pressure differential chambers. As fluidpasses from a smaller restriction to a largerrestriction, it undergoes a significant pressuredrop. With a decrease in the energy pushing thefluid, the velocity of the fluid will also decrease.ProTech forces any fluid that enters the sealthrough 11 different directions and 4 pressuredifferential chambers.Extra care must be taken during the designprocess to avoid introducing features that willcontribute to laminar flow. Designs that rely ondirectional changes alone and use smooth wallchannels tend to take out previously introducedturbulence and convert the flow back to laminar.Such designs are easy to spot because they mustincorporate an internal component, typically anO-ring, in an attempt to match ProTechsperformance.A brand new seal that incorporates an internalO-ring may do very well in performance testing.However, the internal seal is a contacting seal thatwill wear over time. Testing indicates that leakagewill occur in less than 400 hours of run time. Theinternal seal acts as a dam that is holding back apool of contaminants. As soon as there is a breakin the contact, due to wear or the slightest axialmovement, the pooled contaminants will flood intothe bearing housing. The internal seal is also verysusceptible to severe wear from abrasivecontaminants. Sludge deposits also make theinternal seal inoperable. Designs which rely oninternal seals are incapable of excluding even mildwater spray if the internal seal is removed.Depicted below are some of the commondesigns that are available today and they can bedefined by the unitization method that is used.Parkers ProTech is modeled after the Type 1 unitization method which is integrally unitized and a true non-contact design. There are no internal components to wear or damage the seal. Becausethere are no internal components to wear, performance will not diminish over time.Type 2 uses an internal locking ring to unitizethe seal. It is typically a ring made from nylon orother plastic material.Introduction of Turbulence Reduces the Rate of FlowVelocityLaminar TurbulentPressureDifferentialPressure Drops and TurbulenceTurbulentPressure DropTurbulentTurbulentRegionBuffer LayerLaminarSublayer03/28/06Flow PatternsThe graphic shows the flow pattern of contaminants in red.The lubricant flow pattern is in yellow.Type 1IntegralType 2Lock RingType 3O-RingType 4Lip Seal8s r o t a l o s I g n i r a e B h c e T o r P g n i r e e n i g n E8-10 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USATypes 3 and 4 use internal locking rings with adual purpose. Not only do they unitize the seal,they also provide the majority of the sealingfunction. Type 3 uses an internal O-ring and Type4 uses a contact lip seal made of PTFE. If youremove these internal components, the designs willnot function. As these components wear, the sealperformance will diminish over time. Internal sealshave a limited life due to wear caused by axialshaft movement and chemical attack. Over timethe operating temperature will harden the internalseal, making it less effective. The purpose ofinternal componentscan also be negatedby contamination.The photo at rightshows an internalO-ring that is lockedinto a groove bycontamination,completely negatingits intended purpose.Abrasive contaminants will also cause severewearing of internal components.Because internalseals are notprecision balancedcomponents, they canoscillate or wobble atspeed. This cancreate an action thatpumps contaminationinto the bearinghousing. The photo atright shows a streamof water being pumped directly into the bearingcavity by a bearing isolator design that uses aninternal O-ring as the primary seal.Parkers ProTech line of bearing isolatorsfeature a true non-contact design (Type 1) and donot rely on an internal O-ring as the primary seal.Additional internal seals simply are not neededwith a proper labyrinth design.MaterialsMaterial is also an important consideration.ProTech uses advanced proprietary PTFEcompounds making it well suited for harshenvironments such as citric acids found in juiceprocessing and strong caustics such as sulfides inpulp and paper processing. ProTechs superiorchemical resistance allows for the standardizationof a single material within a plant, eliminating theneed to stock duplicate sizes in expensivestainless steel, Hastelloyor other exoticmaterials. Standard chemical compatibility chartsrecommend PTFE for 160 chemicals versus 11 forbronze and 30 for stainless steel.ProTech and aleading metallic isolatorwere soak tested insulfuric acid. After30 days the metallicisolator was heavilycorroded, the O-ringshad disintegrated andthe rotor and statorwere locked together.ProTech showed zero signs of any harmful effectsand could be installed in an application with noperformance issues. The temperature range forstandard material is -40 to +250F (-40 to +121 C).Higher temperature applications can be handledwith alternate materials.Another important material consideration isthe result of initial seal break-in. During initialstart-up, it is very common to have slight contactbetween the rotor and stator. This is a result of theaxial shaft movement that occurs as theequipment reaches operating speed. The axialmovement at operating speed can force the sealsstator and rotor into contact with each other. Thecontact will create a dusting of the seal materialuntil a sufficient amount of material has beenremoved so that the rotor and stator are no longerwearing against each other. The primary concernis this material will find its way into the bearingcavity. With a metallic material, the bearing iscontaminated with a dust that has a detrimentaleffect on bearing life. With ProTech, the dusting isa fine PTFE material, free of glass and otherabrasive fillers, that does not have any harmfuleffects on bearing life or performance. It can beargued that PTFE actually enhances lubrication.InternalCompromised O-RingWater Being Pumped intothe Bearing Cavity03/03/06ProTech vs. metallic isolatorafter soaking 30 days in acid8g n i r e e n i g n E s r o t a l o s I g n i r a e B h c e T o r PCatalog EPS 5350/USA8-11 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comTable 8-4. Extreme Test ResultsMaterial:Expulsion Method:Design Type:BrandPTFESingle-Port2-Pc. UnitizedParkerBronzeSingle-Port2-Pc. Non-UnitizedBrand APTFEMulti-Port3-Pc. UnitizedBrand BBronzeSingle-Port3-Pc. UnitizedBrand COil Leak Test PASS Fail Pass FailWater Pressure Test PASS Fail Fail FailDust Test PASS Pass Fail FailOil Leakage TestWater Exclusion TestDust Exclusion TestTesting and ValidationLaboratory testing has significant advantages over fieldtesting. The lab effectively compresses time and more easilyexplores limits. Before ProTech saw its first field test, it wasput through laboratory tests far more severe than conditionsever encountered in the field. ProTechs effectiveness is alsovalidated by independent laboratory testing.Both ProTech and competitive seals were subjected tothree extreme in-house tests with ProTech clearly emergingas the seal of choice.1. Oil Leakage TestProTech and other seals were subjected to critical oil sealtesting using a machine built to SAE J110 standards. One-hundred hour tests were conducted with severe oil splash.2. Water Exclusion TestThe test machine was modified by mounting five nozzlesat various positions relative to the exterior of the seal tosimulate severe external wash down. Using water atpressures of 30 to 62 psi (2.0 to 4.3 bar), these nozzlesindividually sprayed each seal from a distance of 3" in both astatic mode and while the shaft rotated at various speeds upto 3525 RPM. The nozzles tried to force water past the sealfor nearly two hours.3. Dust Exclusion TestThe test machine was modified with an enclosed chambercontaining a large quantity of fine dust and sand which wasvigorously agitated with the chamber attached to the outsideof each seal area. The equipment operated at speeds up to3525 RPM for a period of 70 hours in an environment that wasliterally a dense dust storm.ConclusionsProTech was the only seal that passed all three torturetests. In addition to lab testing, field trials confirm ProTechsperformance superiority.03/03/068s r o t a l o s I g n i r a e B h c e T o r P g n i r e e n i g n E8-12 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comCatalog EPS 5350/USAInstallationStandard Design InstallationThe ProTech seal is unitized; any attempt todissemble the seal will damage it. After makingany adjustments to the equipment, confirm that theseal is still properly installed.Prior to Installation1. Warning! Disconnect all system power, andfollow all standard safety procedures.2. Remove all sharp edges from the following:a. Lead-in chamfersb. Keywayc. Splinesd. Snap ring grooves3. Clean all foreign debris from bore and shaftareas.Installation1. Lubricate bore and shaft O-rings with system-compatible lubricant.2. Position the sealover the shaft byhand. Seal positionis correct if thestator O-ring istowards the sealhousing as shown.3. Slide seal down theshaft, stopping justbefore the seal housing of the equipment. Usehand pressure only.4. Rotate the seal sothat the drain port iscentered at the sixoclock position.Press seal into boreusing hand pressureonly. If necessary,gently tap seal intobore using a soft-faced tool.DO NOT USE A METALLIC HAMMER ORPUNCH as this may damage the seal.Split Seal InstallationPrior to Installation1. Warning! Disconnect all system power andfollow all standard safety procedures.2. Remove sharp edges on the shaft and borewhere the seal will be installed. Make sure thereare proper lead-in edges.3. Clean all foreign debris from the bore and shaftarea.Installation1. Pre-lubricate the O-rings with a system-compatible lubricant.2. Position the shorter O-ring on the shaft andplace the two halves of the rotor, with the flangesides facing away from the bore, over the O-ringso the O-ring fits into the groove (see Fig. 8-2). (It might help to first paste the O-ring to the shaft with a light coat of grease.) Then place thescrews in the rotor halves and screw the twohalves together loosely. Do not tighten the screws.Figure 8-2. Position the Rotor HalvesPosition the SealInstalling the Seal03/28/06Bearing SideStatorOil DrainRotorDrain Port (Outboard)8g n i r e e n i g n E s r o t a l o s I g n i r a e B h c e T o r PCatalog EPS 5350/USA8-13 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.com3. Place the two halves of the stator over the rotorat the bore side so they interlock with the rotor.Rotate the stator until the drain port is at the sixoclock position. While holding the partstogether by hand, wrap the long O-ring into thestator O-ring groove with the ends of the O-ringmeeting at the 12 oclock position. Gently slidethe seal into the bore while keeping the O-ringin the groove (see Fig. 8-3).Figure 8-3. Proper Installation4. Gently tighten the screws; stopping a few timesto make sure that the shaft can turn freely.Tighten the screws so the halves of the rotormeet. Do not turn the screws more than oneeighth turn beyond where the halves meet. DONOT OVER-TIGHTEN THE SCREWS.After making any adjustments to the equipment,confirm that the seal is still properly installed.Hardware ConsiderationsThe design of ProTech and Millennium bearingisolators use the compression of O-rings to maintaina press fit of the rotor to the shaft and the stator tothe bore. This ensures there is no relative motionor wear between the seal and housing components.Due to lack of dynamic sealing surface, finishconditions are not as critical as they would be witha rotary lip seal.The most common material for shafts is steel.For seal bores common materials are steel, castiron and aluminum. ProTech and Millennium maybe used with a broader range of materials, such asnon-ferrous metals and plastics, that meet theapplication needs.BoresNo special heat treat is required.Surface finish of 32 in Ra (0.81 m Ra) ispreferred but 64 in Ra (1.6 m Ra) in many cases can be tolerated.Lead-in chamfer is required 0.032 to 0.063"(0.81 to 1.6 mm) x 30 with no sharp edges.ShaftsNo special heat treat is required.Surface finish of 32 in Ra (0.81 m Ra) ispreferred but 64 in Ra (1.6 m Ra) in many cases can be tolerated.Shaft lead is not an issue, so ground finish isnot required.Total eccentricity including runout or whip is 0.020" (0.51 mm) T.I.R. for most standard designs. TheProTech 360 design can handle up to 0.003"(0.08 mm). Special designs can tolerate muchmore.HousingShaftDrain Port(6 oclock position)Table 8-5. TolerancesShaft ToleranceShaft Speeds fpm (m/s) Under 5000 (25)Shaft Diameters Inches (mm) All DiametersLSE, LSM, LNE, LNM, LME, LMM,LWE, LWM, LXE, LXM, LDE, LDM,LBE, LBM, SLE, SLM, WDE, WDM,MLE, MLM, MNE, MNM, FSE, FSM,FNE, FNM .002 (0.05)Bore ToleranceCavity Bore Diameter Inches(mm)All DiametersLSE, LSM, LNE, LNM, LME, LMM,LWE, LWM, LXE, LXM, LDE, LDM,LBE, LBM, SLE, SLM, WDE, WDM,MLE, MLM, MNE, MNM, FSE, FSM,FNE, FNM .002 (0.05)03/28/068PPrrooTTe ecchhBBeea arri i nngg IIssooll aattoorrssCatalog EPS 5350/USA8-14 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.comMMaatteerrii aal l ssUnmatched CorrosionResistanceAdvanced proprietary PTFEcompounds mean ProTech is wellsuited for caustic environments such ascitric acids found in juice processingand strong sulfides in pulp and paperprocessing.ProTechs superior chemicalresistance allows for thestandardization of a single materialwithin a plant, eliminating the need tostock duplicate sizes in expensivestainless steel, Hastelloy or other exoticmaterials. PTFE is compatible with over160 chemicals vs. 11 for bronze and 30for stainless steel.Metallic MillenniumBearing IsolatorSeal MaterialsPTFE Materials-1 20210 Proprietary Graphite Filled PTFEGraphite filled PTFE, offers low wear, low coefficient offriction, a superior material for dynamic applications.-2 20999 Food Grade (FDA) Mineral Filled PTFEMineral filled PTFE that meets FDA requirements to achieveimproved wear and longer life. White in color.-5 20113 Proprietary Graphite Filled PTFEProprietary filled PTFE, offers low wear and exceptionalthermal stability. Used in larger diameters where boreretention is critical.-7 20995 Anti Microbial PTFEProprietary filled PTFE that meets FDA requirementsapproved for dairy contact, offers superior wearcharacteristics that exceed other materials used in dynamicfood and drug processing equipment applications. White incolor. Material contains anti microbial additive that preventsgrowth of bacteria.-8 20990 FDA 3A PTFEMineral filled PTFE that meets FDA requirements to achieve:improved wear, longer life and FDA clearance. White in color.Meets 3A sanitary standards for USDA food and dairy productcontact.Metallic-B Bronze C93200 (SAE 660)The most popular bronze bearing material, SAE 660, isparticularly suited for medium to relatively high speeds. SAE660 provides good hardness, strength and wear resistance;excellent anti-frictional qualities and good conformability.Excellent machining properties.03/28/068s l a i r e t a M s r o t a l o s I g n i r a e B h c e T o r PCatalog EPS 5350/USA8-15 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.com-S 304 Stainless SteelCorrosion Resistance: Excellent exceeding that of Type302 in a wide variety of corrosive media including hotpetroleum products, steam combustion gasses. Frequentlyused in the food and beverage industry which requires a highdegree of sanitation and cleanliness.316 Stainless SteelCorrosion Resistance: Good resistance to a wider range ofchemicals than Type 304. Highly resistant to the complexsulphur compounds used in pulp and paper processing. Alsoresists attack of marine and corrosive industrial atmospheres.This type is also highly resistant to pitting and withstandscorrosive actions of acids, dyes, and salts used in theprocess, textile and pulp industries. Applications include themanufacture of pumps, valves, textile and chemicalequipment.Carbon SteelCorrosion resistance: Poor with no corrosion treatment.Minimum physical properties of 36,000 psi yield strength and58,000 psi tensile strength. Applications include a widevariety of industrial equipment.Table 8-6. Standard Seal Material Temperature RangeMatl.Code Material Min.TempCont.Temp.PeakTemp.-1 20210 Proprietary Graphite FilledPTFE-40 F 250 F 250 F-40 C 121 C 121 C-2 20999 (Food Grade FDA) MineralFilled PTFE-40 F 250 F 250 F-40 C 121 C 121 C-5 20113 Proprietary Graphite FilledPTFE-40 F 250 F 250 F-40 C 121 C 121 C-7 20995 Anti Microbial PTFE -40 F 250 F 250 F-40 C 121 C 121 C-8 20990 FDA 3A PTFE -40 F 250 F 250 F-40 C 121 C 121 C-B Bronze C93200 (SAE 660) -40 F 400 F 400 F-40 C 204 C 204 C-S 304 Stainless Steel -40 F 400 F 400 F-40 C 204 C 204 CSpecial 316 Stainless Steel -40 F 400 F 400 F-40 C 204 C 204 CF 0 0 4 F 0 0 4 F 0 4 - l e e t S n o b r a C l a i c e p S-40 C 204 C 204 CNote: Other materials and custom compounding available. Contact Parkerfor more information.03/28/0688-16 Parker Hannifin CorporationEPS DivisionToll Free: (800) 233-3900www.parkerseals.coms r o t a l o s I g n i r a e B h c e T o r P s l a i r e t a MCatalog EPS 5350/USAO-Ring Materials-1 Fluorocarbon (FKM)Fluorocarbon (FKM) has excellent resistance to hightemperatures, ozone, oxygen, mineral oil, synthetic hydraulicfluids, fuels, aromatics and many organic solvents andchemicals. Special FKM compounds exhibit an improvedresistance to acids, fuels, water and steam.-2 Fluorosilicone (FVMQ)FVMQ contains trifluoropropyl groups next to the