Catalog 390

KAYDON/BEARINGS

Large Bearing Design Manualand Product Selection GuideCatalog 390

Table of Contents

Introduction ................................................................................................................................................................................... 3

Design Features ........................................................................................................................................................................... 4-5

Preliminary Selection Guide ...................................................................................................................................................... 6-7

Application and Load Analysis ................................................................................................................................................ 8-10

Typical Mountings ....................................................................................................................................................................... 11

MT-Series Bearings and Load Ratings ................................................................................................................................... 12-13

RK-Series Bearings and Load Ratings .................................................................................................................................... 14-15

Custom Four-Point Contact Ball Bearings and Load Ratings ............................................................................................... 16-17

Eight-Point Contact Ball Bearings and Load Ratings ........................................................................................................... 18-19

WireX® Roller Bearings .......................................................................................................................................................... 18-19

KH-Series ................................................................................................................................................................................ 20-21

Special Bearing Capabilities ........................................................................................................................................................ 22

Load Rating Charts ................................................................................................................................................................. 23-24

Installation and Care of Kaydon Bearings .............................................................................................................................. 25-31

I.–Design Considerations (for the equipment designer) ........................................................................................................ 25-29

II.–Installation Instructions (for the equipment builder) ...................................................................................................... 30-31

III.–Maintenance Instructions (for the equipment user) ............................................................................................................ 31

Applications Data Sheet .............................................................................................................................................................. 32

Warranty Information .................................................................................................................................................................. 33

2

3

Introduction

Kaydon CapabilitiesKaydon has been America’s leading pro-ducer of large diameter custom bearingssince its founding in 1941. Manufactur-ing operations have expanded steadily tomeet ever growing market needs since1976.

Kaydon manufactures bearings up to 180inches outside diameter using the mostmodern facilities and equipment in theindustry. Continuing expansion andmanufacturing versatility have led toour position as the leading supplier of alltypes of large diameter combination loadbearings. Kaydon is unique in the breadthof product capabilities offered, alwaysstriving to match the best bearing typewith your application needs.

Standard bearingsKaydon’s long history of serving theneeds of equipment and manufacturershas resulted in two series of standardbearings to fit many common applica-tion needs. The RK-Series of light-weight turntable bearings have provencapable of satisfying many requirementsat moderate cost—with the advantagesof short lead time or stock availability.The new, expanded MT-Series of stan-dard turntable bearings combine quickdelivery with maximum capacity andvalue to fit an even wider variety ofapplications. Many other bearings shownin this catalog are produced on a regularbasis and offer short lead time atmoderate cost.

Custom bearingsWhile other manufacturers may special-ize in one or two specific bearing types,Kaydon’s broad experience and capabili-ties allow us to match the product toyour requirements—not ours. Where aspecial need exists, Kaydon can fill itwithout sacrificing system performance.Often, we can supply bearings which fillthe need with minimal alteration oradditional costs to the design. For truly

unique applications, our fully staffedengineering department can design theoptimum solution.

Bearing types•Four-point contact ball bearings, as

well as Kaydon’s patented 8-pointcontact ball bearings, are used as swingbearings in cranes, excavators, aerialplatforms and other types of construc-tion and material handling equipment.These bearings have also been appliedsuccessfully in machine tools, radarand medical equipment.

•Biangular roller bearings are used inapplications demanding higher preci-sion and stiffness but requiring lessstatic load capacity, such as indextables, positioners, antenna mountsand military gun turrets.

•Inserted raceway–WireX®–bearingswith single, double or triple rows offerimportant weight savings advantagesand are found in high performanceapplications such as military vehicleturrets.

•Plastic ball 4-point contact andangular contact thrust bearings arealso available for specializedapplications.

Total capabilitiesKaydon offers the bearings to fit yourneeds. Ball and roller types in single andmulti-row designs. Solid or inserted wireraceways. Geared raceways, both inter-nal and external. Bearings for radial,thrust, moment and combined loading.Capacities, materials, seals and configu-rations to fit a variety of applications.And the design and application engi-neering service that has tailored the bestbearing values to the world’s toughestbearing applications.

If you don’t see what you want in thiscatalog, call us at (231) 755-3741. Wewill be glad to supply technical assis-tance, lead time information and quota-tions on bearings to fill your requirementsor specifications.

PrecisionMany devices, such as machine tooltables and radar antennas, require ahigh degree of accuracy and are de-pendent upon the bearings to achieveit. A single four-point contact ball orbiangular roller bearing is ideal forthese applications. Integral gears andmounting holes reduce the number ofcomponents and tolerance buildup,resulting in maximum accuracy andsimplification of design. Early consul-tation with Kaydon can be invaluablein determining the optimum bearingand mounting.

The bearings listed in this catalog aremanufactured to a standard precisionsuitable for many commercial applica-tions, but Kaydon also manufacturesbearings of higher precision. Theengineering principles discussed inthe manual also apply to bearings ofany precision level.

Bearings with radial and axial runoutsof less than .0002 inches T.I.R. andgears of AGMA Class #10 or bettercan be furnished. Where extremerigidity is required, very high springrates can be maintained. Kaydonachieves these results through theuse of modern precision equipment,experienced personnel, and speciallydeveloped manufacturing techniques.

Combined with other features of largediameter bearings—high load capac-ity, small space requirement, largecenter hole, grease lubrication, andease of installation, high precisionand rigidity make possible greatlyimproved performance in suchapplications as:

•Grinding machines•Turning and boring machines•Index tables•Scientific and medical instruments•Radar, height finders, positioners

and gun directors•Ocular and radio telescopes•Logging machinery•Material handling equipment

4

Bearing Design Features

Whether used in heavy-duty off-roadvehicles, precision medical equipmentor high accuracy military radars, largediameter Kaydon bearings share manydesign features. There are importantdifferences however, which often dictatethe optimal bearing selection for a givenapplication. These pages outline theprimary features of each bearing type.

Turntable bearing advantagesOver the years demands have increasedfor equipment economy, performance,and reliability. As a result, four-pointand eight-point contact ball bearingshave replaced the older, less efficienthook rollers and kingpost assemblies.Turntable bearings provide smoothrotation and high radial, thrust andmoment load capacity in a compactdimensional envelope. With a Kaydonturntable bearing there is no need for acenter shaft or kingpost, so the bearingcenter space is open and available forhydraulic piping or conduit runs.

Additionally, turntable bearings incor-porate many special features such asintegral gearing, through-drilled ortapped mounting holes and contactseals. These features simplify the job ofthe equipment designer, lower manufac-turing costs, and facilitate systemmaintenance.

Importance of proper selec-tion, installation and useTurntable bearing applications aretypified by heavy loading and slow,intermittent or partial rotation.

Bearing failure is therefore seldom dueto classic rolling contact fatigue. Inother words, calculated bearing life isnot usually a major consideration inturntable applications, especially inconstruction equipment.

Turntable bearings are usually selectedon the basis of static load capacity, suit-able integral gearing, and other specialfeatures. Turntable bearing failure is

often the result of practical consider-ations not covered by classical rollingbearing theory—such as nonuniformsupport structure design, lack of lubrica-tion, improper selection or applicationof fasteners, overloading beyond equip-ment specifications, and other abuses.

The purpose of this manual is to provideguidelines for system design and turn-table bearing application, and to cautionequipment designers and users of oneprinciple: Large-diameter bearings arenot commodity products. Each bearingis a custom design or a custom applica-tion of an existing bearing design. Ineither case, the bearing manufacturershould be involved in the design stage.

Four-point contact ballbearingsFour-point contact ball bearings canaccept combinations of radial, thrustand moment loads. This is possible dueto the unusual geometry of the raceways(or ball grooves). The ball groove ineach race has two radii that are largerthan the ball radius. The centers ofthese two radii are offset from the centerof the ball radius. This results in a“Gothic Arch” configuration in each ofthe raceway grooves, making it possiblefor the two grooves to contact the ballat four points.

High thrust and moment capacity isobtained in a four-point contact ballbearing by its deep raceway grooves.These allow high initial contact anglesbetween the balls and raceways andincrease the thrust and moment capac-ity. The deep grooves also accommodatethe contact angle increase which results

from ring stretch and ball deflectionunder load.

Precision grinding of raceways isnecessary to control accuracy of contactangles, close ball to raceway conformity,diametral clearance and raceway finish.These design features, along with propermaterial selection, assure the properfunction of the four-point contact ballbearing.

Eight-point contactball bearingsThe eight-point contact ball bearing wasdeveloped by Kaydon to satisfy require-ments for maximum load capacity withina given envelope, especially in larger sizebearings.

As shown below the eight-point contactball bearing is an annular bearing withtwo rows of balls. The unique feature ofthis bearing lies in the utilization of the“Gothic Arch” or four-point contactinternal geometry in both rows.

Functionally, the bearing may be con-sidered to be two single row, four-pointcontact bearings with adjacent faces.

The four points of contact permit eachrow of balls to accept radial, axial, ormoment loads, or a combination of thethree. Through precise grinding tech-niques, raceways are closely matched forparallelism and size, providing a highdegree of load sharing between rows.Test results have confirmed that thesecond row of balls provides and addi-tional 80% capacity over that providedby a single row.

5

Biangular roller bearingsBiangular roller (cross roller) bearingswill support the same types of load asthe four-point and eight-point contactball bearings.

To accomplish this universal load carry-ing capability, the bearing is designedwith V-groove raceways, providing tworoller paths in each ring. The rollershave a length slightly less than theirdiameter and are positioned so thatadjacent rollers contact different sets ofraceways, with the axes at right anglesto each other. Positioned in this mannerthe rollers transmit load along perpen-dicular sets of 45° contacts. The actionof the bearing under various types ofloading is thus analogous to that of thefour-point contact ball bearing.

While a roller of length and diameterapproximating a given diameter of ballhas more load carrying capacity, thestatic thrust and moment capacity of abiangular roller bearing is less than thatof a four-point contact ball bearing ofcomparable size. The reason for this isthat only alternate rollers resist a uni-directional axial load. In some cases,capacity in one axial direction may beincreased by orienting more rollersalong one axis than the other, with aresulting decrease in capacity in theopposite direction.

The main advantages of biangular rollerbearings are greater stiffness and conse-quent superior spring rate, as well astolerance of mounting surface irregulari-ties and resulting deflections. When

deflection under load must be minimized,or when bearing turning torque is criti-cal this bearing may be given preferenceover a four-point contact ball bearing.

WireX® inserted racewaybearingsWireX® bearings are generally used inapplications requiring maximum weightreduction and corrosion resistance. Theyare generally custom designed to supportspecific combinations of radial, thrustand moment loads. Gear teeth can becut in the inner or outer ring, and boltholes provided for mounting.

The bearing rings have machined seatsto position the inserted wire raceways,which are held in place by bearing loadstransmitted through the rolling ele-ments. The rolling elements (usuallyrollers) and wires are usually made ofstainless steel.

Bearing rings can be made of manydifferent materials. When aluminum isused the complete bearing can be madeof corrosion resistant material and mayresult in weight savings of up to 50%.The use of aluminum rings may alsoeliminate thermal expansion problemswhen the bearing is mounted to alumi-num structures.

Another advantage of WireX® bearingsis their high tolerance of non rigid andout-of-flat mounting structures. Irregu-larities can be accommodated by the freemovement of the wire inserts in theircircular seats.

WireX® bearings can often be rebuilt—a substantial savings when compared tocomplete bearing replacement.

Three-row roller bearingsThree-row roller bearings offer thehighest capacity, using three separaterows of rollers. The top and bottom rowsabsorb thrust loading, each row in theopposite direction, and operate togetherto handle moment loading. The inter-mediate row handles radial loads.Because each row is independent,frictional torque is low.

Plastic ball bearingsLarge diameter bearings with plasticballs are provided for light duty, low loadapplications. Raceways are V-groovesmachined in aluminum or steel bearingrings.

These bearings tolerate mountingdistortions well, operate with lowtorque, and are relatively inexpensive.They are capable of handling radial,thrust and moment loads. Trade-offsinclude reduced load capacity andpositional accuracy.

Bearing Overview Selection Guide

6

Maximum CapacityGeneral Typical Rolling Outside Gear

Moment Thrust Radial Typical

Description Cross Section Element Diameter Options(ft.-lbs.) (lbs.) (lbs.)

Applications

Four-Point Machine ToolsContact Ball Aerial Devices

Medical Equipment Custom

10,000,000 6,000,000 1,300,000Radar

(pg. 16-17) 16" to 180" •Non- CranesBall geared Utility Cranes

MT-Series •Internal900,000 600,000 200,000

Excavators (pg. 12-13) 12" to 48"

•External

RK-Series140,000 175,000 60,000 (pg.14-15) 20" to 47"

Lightweight •Non- Military TurretsFour-Point Geared Medical EquipmentContact

PlasticTo 60" •Internal Consult Kaydon General Purpose

(pg. 22)Ball

•External

Eight-Point Large CranesContact Excavators(pg. 18-19) •Internal Marine Cranes

Ball To 180" •External 15,000,000 9,000,000 2,000,000 Severe Environment

KH Series •Non- Precision IndexingPrecision Geared Rotary TabesBearing Ball 20" to 32" 40,000 43,000 20,000Assemblies •External(pg. 20-21)

CustomizationMost of the bearing designs shown onthese pages can be produced with user-defined options, including but notlimited to special paints and platings,low temperature stabilization and specialcages for high speed and horizontalmountings.

PrecisionPrecision gears, runouts, preloads andtorque control are available to suitspecific applications. AGMA Class 6gears are standard, gears up to AGMAClass 12 can be supplied on request.

7

Maximum CapacityGeneral Typical Rolling Outside Gear

Moment Thrust Radial Typical

Description Cross Section Element Diameter Options(ft.-lbs.) (lbs.) (lbs.)

Applications

BiangularRoller(pg. 22) •Internal

Radar

Roller To 180"•External

7,000,000 3,000,000 1,400,000Military turretsMachine toolsExcavators

LightweightBiangularRoller •Internal(pg. 22) Roller To 180"

•External2,500,000 1,250,000 575,000 Military turrets

Three-RowRoller Radar(pg. 22) •Internal Cranes

Roller To 180"•External

18,000,000 12,000,000 4,000,000 ExcavatorsStackers & reclaimersHeavy mill equipment

InsertedRace •Non-WireX® Geared(pg. 18-19) Roller To 120" •Internal 1,820,000 1,000,000 370,000

Military turrets

•External

Radar

InsertedRaceBiangular •InternalWireX® Roller To 120"

•External1,830,000 900,000 370,000

Military turrets

(pg. 22)Radar

InsertedRaceThree-Row •InternalWireX® Roller To 120"

•External2,250,000 1,125,000 400,000

Military turrets

(pg. 18-19)Radar

SpecialConfiguration(pg. 22)

Ball To 180"Consult Kaydon for design and applicationengineering assistance with your specificcustom bearing requirements.

Application and Load Analysis

8

★ See warranty, page 33.

Many factors must be considered inselecting and applying an antifrictionbearing. Chief among these are type andmagnitude of loading, speed of rotation,and accuracy.

For most applications in constructionand material handling equipment, loadis the primary concern. Speed andaccuracy are relatively unimportant butdeserve consideration along with otheritems such as friction torque, gearing, andmounting. Other applications, such asprecision medical equipment, require ahigh degree of accuracy and close control oftorque, but have relatively low loading.

LoadBecause a turntable bearing accepts alltypes of loading, the main concern withload is its magnitude. See Pages 9-11 forload determination and bearing selection.

Turntable bearings are designed prima-rily for dominant axial (thrust) and/ormoment loading. In applications whereradial load is significant or the dominantload, it may be advisable to use a bearingwith a reduced contact angle. Radialload of a magnitude equal to 10% or lessof the axial load may be neglected. For atentative selection, radial load in excessof 10% may be converted to equivalentthrust load by using a multiplicationfactor of 5.

SpeedThe application of a standard large-diameter bearing is normally limited tointermittent rotation at a maximumspeed of 500 feet per minute at the pitchline (about 50 RPM for a bearing pitchdiameter of 3 feet). Where continuousrotation under load occurs or the speedof rotation is greater than that recom-mended, the standard bearing design canbe modified. This modification mayinclude revisions in contact angle andmanner of ball separation.

In applications where the speed ofrotation is greater than 1100 feet perminute, a different type of bearing mustbe used.

AccuracyPositioning of the rotating member rela-tive to the stationary structure may be ofconcern. With the bearing races securelyfastened in a round condition on flatmounting surfaces, the main source ofpositioning error is internal bearingclearance—bearing runouts being smallby comparison. See Page 22.

Four-point contact bearings are furnish-ed with sufficient internal clearance toallow for some imperfections of mount-ing surfaces and for small amounts ofdeflection under load. Bearings can befurnished with reduced internal clear-ance to minimize “rock.” Extra careshould then be taken to assure theinstalled bearings will be round and flat.

Friction torqueIn most applications of large-diameterbearings the force required to overcomebearing friction is small compared tothat required to overcome the inertia ofthe mass being supported—provided thebearing is properly mounted and containsthe standard internal clearance. Bearingclearance is designed to minimize thepossibility of tight spots resulting fromordinary imperfections in the mounting.

A bearing distorted by out-of-flat or out-of-round mounting surfaces may requirea tremendous amount of turning torque.The same is true for a bearing mountedon a structure which deflects locallyunder load. Unfortunately, this phenom-enon is not always recognized untilactually experienced.

Other factors affecting bearing frictionare bearing contact angle, separator andlubricant. A low torque requirementshould be referred to Kaydon for specialattention.

GearsGears furnished integral with turntablebearing races commonly have an AGMAStandard 20° full depth or stub toothform the some provision for backlash.Where required, however, modifications

of the basic tooth forms and alternatepressure angles can be furnished. Foradditional strength or where surfacehardening is required, a full-round filletcan be provided.

Safe tangential tooth loads are given forthose bearings listed; however, it is rec-ommended that the machine designerverify the adequacy of the gear for hisapplication based upon his own methodsof calculation and past experience.

Bearing and pinion mountings lackingin rigidity can result in tooth endloading under the heavier loads. Manydesigners find it desirable to crown thepinion to compensate for this undesir-able effect.

★ Mounting holesThe preferred method of attaching turn-table bearings is to bolt through bothraces with full circles of equally spacedfasteners. It is recognized, however, thatthe design of the mating structures maydictate the use of special bolt patternsand that assembly procedures mayrequire tapped holes. There is noobjection to such mountings, providingit is determined by actual testing, as wellas analysis, that the fasteners will haveadequate strength to sustain themaximum moment loads possible. SeePages 26-27 for more on bolts.

Weld rings and weld bandsWelding offers an optional method ofattaching one of the races of turntablebearings.

The bearing is furnished with a lowcarbon steel weld ring or band welded tothe race. The ring can be welded to themachine without injury to the bearing,provided proper procedures and precau-tions are exercised.

While welding has certain advantages,it is inconvenient to effect majormaintenance or replacement of thebearing if damage should occur.

9

Applied ForcesThrust & Moment Loading

W = weight of mass supported in poundsX = distance in feet from W to axis of rotation

Bearing Loads

T = thrust or axial load = W in poundsR = radial load = 0M = moment load = W • X in pound-feet

Applied ForcesRadial, Thrust & Moment Loading

W = weight of mass supported in poundsFt and Fr = applied forces in poundsX, Y, & Z = moment arms in feet

Bearing Loads

T = thrust or axial load = W + Ft in poundsR = radial load = Fr in poundsM = moment load = (W • X) = (Ft • Z)_

(Fr • Y) in pound-feet

Applied ForcesRadial & Moment Loading

W = weight of mass supported in poundsY = distance in feet from W to plane of rotation

Bearing Loads

T = thrust or axial load in pounds = 0R = radial load = W in poundsM = moment load = W • Y in pound-feet

SealsSeals are normally included in Kaydonlarge-diameter bearings and are recom-mended for bearing protection evenwhere external seals or shields are pro-vided. Gear protection is also importantand should be considered when design-ing the bearing mount.

Loading holeThe rolling elements in Kaydon bearingsmay be inserted through a hole drilledradially through the ungeared race andthen plugged. The area of the racewayinterrupted by this hole is relieved toprevent it from receiving load. When-ever possible, however, the loading holeshould be positioned out of the maxi-mum load zones.

LubricationOne or more grease fittings or lubrica-tion holes are provided in all turntable

bearings. Additional lube holes can befurnished on request. For furtherdiscussion of lubrication, see Page 26.

Mounting and installationThis topic is discussed in detail onPages 25-31.

Normal applicationSpecial attention must be given to bear-ing application whenever conditions aredifferent from those considered normal.For a “normal application” of turntablebearings the following conditions shouldapply:•Vertical axis of rotation•Predominant thrust and moment loading•Radial load not in excess of 10% of

the thrust load•Intermittent rotation with pitch line

velocity limited to 500 FPM•Operating temperature within -40°F to

+ 125°F

•Mounting surfaces machined andreinforced to limit deviation from atrue plane to the amounts shown inFigures 40 and 41 on page 25

•Installation procedure to assureroundness of both races, such as byapplying a centered thrust load whileskip tightening the bolts

•Provision for periodic relubrication•Provision for periodic checking of

mounting bolts to verify their propertightness

Basis for bearing load ratingsThe bearings in this catalog are designedprimarily for use in applications whereapplied loads may be high but speed ofrotation is slow and operation is usuallyintermittent. In such applications, bear-ing fatigue life is of little concern andselection of the bearing may be based onits static rating.

Figure 1 Figure 2 Figure 3

W

X

R

T

M

W

XY

Fr

FtZ

T

M

R

W

Y

T

R

M

10

Static rating is defined as the maximumload which may be applied to the bear-ing while it is stationary without impair-ing the smoothness of subsequentoperation.

Load rating curves are supplied for mostbearings listed herein. These curvesrepresent the maximum combined axialand moment loads which may be appliedto the bearing. When selected from thecurves for a crane or application withsimilar operating characteristics mostbearings can be expected to last for thelife of the machine if the loading used inthe selection is based on the maximummachine rating. Use of the curves isexplained under Selection Procedures.

Typical applied loadsTo select a bearing for a given load con-dition, the actual bearing loads must bedetermined from the forces applied to theequipment in which the bearings will beinstalled. These forces will commonly beapplied perpendicular to the axis of thebearing (radial force) or parallel to theaxis (axial or thrust force). If not appliedin either manner, the force can beresolved into components acting alongsimilar lines.

Location of the applied forces relative tothe bearing will determine the momentload on the bearing. Radial forces mustbe located relative to the plane of therolling elements with axial forces locatedrelative to the bearing axis.

Figures 1, 2, and 3 on the previous pageillustrate typical applications of externalforces and the resulting bearing loads.

Bearing load analysisTo determine the effects of combinedloading, Kaydon uses a unique freebodyanalysis. This analysis was developed aspart of a study of large diameter anti-friction bearings conducted for theMassachusetts Institute of Technologyunder a United States Air Force contract.As illustrated in Figures 1-3, the applied

load system is converted to an equiva-lent force diagram, as shown below.

In this analysis the loaded race isconsidered to constitute a freebody inspace acted upon by the applied loadsand stabilized through the ball contactsby the other race.

A plane is passed through the axis andthe lines of action of the applied loads.For purposes of calculating the reactionsR1, R2, R3, and R4, they are assumed toact only on the two balls whose centersare in the selected plane. Once thereactions are determined, the maximumreaction is assumed to be distributedover a limited number of balls based onthe eccentric nature of the applied loads.The latter is determined from a compari-son of the magnitudes of the reactions.

While four possible reactions are indi-cated, only three of these will occur dueto bearing deflections under the appliedforces. To solve for the reactions, onemust be assumed equal to zero. Thethree remaining reactions are thendetermined by the summation ofmoments about points selected from A,B, C, and D. If one of the calculatedreactions is found to be negative, theoriginal assumption of the inactivereaction is incorrect and a new assump-tion must be made.

In general, bearings for construction,material handling, and similar types ofequipment may be selected from theload rating curves. However, with radialload exceeding 10% of the thrust load is

present, Kaydon should analyze all loaddata and recommend the bearing.Significant or dominant radial load maydictate the selection of a larger bearingor a modification of the contact angle.

A detailed Kaydon load analysis is alsorecommended for those applications inwhich there is an appreciable variationin the load and operating conditions,and maximum loading is infrequent.This analysis can result in selection of asmaller, more economical bearing thanthat selected on the basis of maximumloading only.

Calculated data includes maximum ballload, race size change, ball contact de-flection, change in contact angle, size ofthe contact area, stress in the contactarea, subsurface shear stress, static factorof safety, dynamic factor of safety, andbolt factor of safety.

Selection procedure1. Review preceding material, especially

NORMAL APPLICATIONS beforeproceeding with selection.• For unusual conditions, consult a

Kaydon representative.• For normal applications, proceed as

follows.2. Determine the preferred mounting

arrangement-pinion and gear location,etc.

3. Determine the maximum bearingloads (see Figure 1-3). Consider allapplied forces including work loads,wind loading on large superstructures,and gear loads if significant.• Consider the weights of all members

of the structure supported by thebearing.

• Where several possible combina-tions of load exist, calculate all con-ditions to assure inclusion of themaximum condition. A crane, forexample, usually has a number ofconditions of load versus workingradius.

• Multiply the calculated loads by theapplicable service factor:

R

T

MB

CA

R1

R4

OO

R2

PD sin O

R3

DPD

PD tanO2

PD = ball pitch diameterO = contact angleR1, R2, R3, R4, = bearing reactions

11

Kaydon bearings can be designed tosuit a number of mounting arrange-ments. The six basic arrangements areillustrated below. These can be variedto suit requirements peculiar to aspecific application. Such variationsinclude types of holes, location and

number of lube holes, omission ofintegral gear, incorporation of specialseals, etc.

The mounting structures shown areintended to be illustrative only. Impor-tant details in design such as mounting

Typical mountings

plate thickness, location and numberof stiffening members, and boltlengths must be determined by theequipment designer.

Figure 4Pinion is attached to stationary outer raceand rotates geared inner race carrying upperstructure.

Figure 7Pinion is attached to rotating upper structure

carried by outer race.

Figure 5Pinion is attached to rotating upper structurecarried by inner race.

Figure 8Upper structure rotates on inner race with drive

separate from bearing.

Figure 6Pinion is attached to stationary inner race androtates geared outer race carrying upper structure.

Figure 9Upper structure rotates on outer race with driveseparate from bearing.

Application Service FactorMobileCrane .................................... 1.00Excavator, Pedestal Crane ............... 1.25Logger ............................................... 1.50

4. Refer to the list of bearings and theirload rating curves. Pages 12-24.(Curves based on service factor =1.00.)

5. Select a bearing on the basis ofpreferred mounting arrangement andmaximum load condition.

• A bearing has adequate capacity forany combination of loading whichresults in a point of intersection onor below its rating curves.

• Check all load conditions in caseswhere an uncertainty exists as towhich is the maximum condition.

• In some cases there will be a choiceof several bearings having therequired load rating.

• For maximum economy, select thebearing with the smallest diametercompatible with other requirementssuch as space limitations and loca-tion of the drive mechanisms.

6. Check capacity of the gear—see Pages 27-29.

7. Check capacity of the mounting bolts—see Pages 26-27.

8. Submit to Kaydon for engineeringreview.

Refer to mounting instructions on pages 25-31.

Table 2—External gear MT Series (Figure 11)

Outline dimensions (inches) Hole data Gear data—20° pressure angle

No. No.Max. ReferenceModel Kaydon Reference

holes holesNo.

BHNtangential Approx. momentno. P/N no. OD ID W TO TI OS BCO

outerHO BCI

innerHI PD DP FW

teethcore

tooth wt. lbs. loading ratinghardnessload (lbs.)ft.-lbs.

MTE-145 13109 T7-9E1 12.286 5.709 1.968 1.732 1.732 .236 10.630 16 .562 6.890 16 .562 12.000 5/7* 1.732 60 277-321 7,140 38 26,000MTE-145X 12600 T7-9E3 12.286 5.709 1.968 1.732 1.732 .236 10.630 16 .594 6.890 16 .594 12.000 5/7* 1.732 60 277-321 7,140 38 30,600MTE-210 11536 T7-11E1 14.686 8.268 1.575 1.496 1.496 .079 13.190 16 .562 9.449 20 .562 14.400 5/7* 1.496 72 262-302 5,810 38 44,500

MTE-210X 12610 T7-11E9 14.686 8.268 1.968 1.732 1.732 .236 13.190 16 .594 9.449 20 .594 14.400 5/7* 1.732 72 277-321 7,290 44 52,100MTE-265 11487 T7-14E3 17.086 10.433 1.968 1.732 1.732 .236 15.354 18 .562 11.614 24 .562 16.800 5/7* 1.732 84 277-321 7,330 57 62,000

MTE-265X 12620 T7-14E14 17.086 10.433 1.968 1.732 1.732 .236 15.354 18 .594 11.614 24 .594 16.800 5/7* 1.732 84 277-321 7,330 57 71,900MTE-324 11054 T8-17E 20.486 12.750 2.062 2.022 2.022 .040 18.875 20 .625UNC 14.375 20 .625UNC 20.2 5/7* 2.022 101 277-321 8,700 98 101,700

MTE-324X 12630 T8-17E28 20.486 12.770 2.375 2.063 2.063 .312 18.875 20 .688 14.375 20 .688 20.200 5/7* 2.063 101 277-321 8,863 99 102,100MTE-415 12640 T8-20E5 24.650 16.250 2.375 2.063 2.063 .312 22.250 16 .813 17.750 20 .813 24.250 4** 2.063 97 277-321 10,420 132 159,200MTE-470 12650 T8-22E10 26.900 18.500 2.375 2.063 2.063 .312 24.500 18 .813 20.000 24 .813 26.500 4** 2.063 106 277-321 10,460 147 191,600MTE-540 12670 T8-25E1 29.650 21.250 2.375 2.063 2.063 .312 27.250 24 .813 22.750 28 .813 29.250 4** 2.063 117 277-321 10,520 163 232,000MTE-590 12675 T10-28E1 33.534 23.125 2.875 2.563 2.563 .312 30.625 18 .938 24.875 24 .938 33.000 3** 2.563 99 277-321 17,290 283 338,700MTE-705 12680 T10-32E3 38.201 27.750 2.875 2.563 2.563 .312 35.250 24 .938 29.500 28 .938 37.667 3** 2.563 113 277-321 17,390 332 443,200MTE-730 12685 T12-35E3 41.850 28.750 3.250 2.880 2.880 .375 38.000 20 1.063 31.000 24 1.063 41.200 2.5** 2.630 103 277-321 21,290 498 588,000MTE-870 12690 T14-40E6 47.444 34.250 4.250 3.875 3.875 .375 43.875 24 1.188 36.250 28 1.188 46.800 2.5** 3.875 117 277-321 31,620 780 873,800

MT-Series Bearing Selection Data

12 13

Kaydon’s standard line of MT-Seriessmall-bore turntable bearings are ideallysuited for light to medium duty applica-tions such as truck-mounted cranes,hoists and nonprecision industrial tablesand positioners. With additional sizesnow offered from 20" to 47" O.D.,heavier duty applications can be servedwith a standardized bearing design.

Recent design changes and manufactur-ing upgrades have allowed Kaydon toincrease load capacity ratings. We havealso incorporated a new sealing systemwhich provides maximum lubricantretention with minimal seal wear.

MT-Series bearings are an economicalreplacement for kingpost designs andutilize the same four-point contactdesign concept as our heavier dutyturntable bearings, providing excep-tional radial, thrust and moment loadcapacities. They are available with orwithout external gears.

Precision manufactured versions ofthese standard bearings can be appliedin machine tool, material handling,power transmission, radar and roboticapplications. For additional informationon runout control, gear precision,bearing preloading and special coatingsavailability please consult with Kaydonprior to selecting a bearing.

Table 1—Non geared MT Series (Figure 10)

Outline dimensions (inches) Mounting holes ReferenceModel Kaydon Reference

OD ID W TO/TI BCO BCI No. holes Hole dia.

Approx. momentno. P/N no.

Inner Outer HI/HOwt. (lbs.) load rating

ft. lbs.MTO-145 13102 T7-9P1 11.811 5.709 1.968 1.732 10.630 6.890 16 16 .562 37 26,000

MTO-145X 12700 T7-9P4 12.286 5.709 1.968 1.732 10.630 6.890 16 16 .594 41 30,600MTO-210• 11471 T7-11P1 14.370 8.268 1.575 1.496 13.190 9.449 20 16 .562 38 44,500

MTO-210X• 12710 T7-11P9 14.686 8.268 1.968 1.732 13.190 9.449 20 16 .594 48 52,100MTO-265 11473 T7-14P1 16.535 10.433 1.968 1.732 15.354 11.614 24 18 .562 54 62,000

MTO-265X 12720 T7-14P9 17.086 10.433 1.968 1.732 15.354 11.614 24 18 .594 61 71,900MTO-324 11053 T8-17P1 20.486 12.750 2.062 2.000 18.875 14.375 20 20 .625 UNC 105 102,400

See load rating charts on page 23.

Note: Bearings with suffix “X” in the model number are newly designed to provide additional loadcapacity and are recommended for new application. They will appear 9/16" diameter fasteners.*Fellows Stub**USA Standard Stub•Consult Kaydon for instruction on relubrication of this bearing.★ Warning–Damage to equipment and danger to human life can result from failure to heed therecommendations in the text identified by the warning symbol.

Figure 10 Figure 11

ID

TO WTI

BCIBCOOD

HI

HO ID

TO WTI

BCIBCO

OD

HI

OS

PD

HO

Matching pinions available from stock. See Table 5A.

Matching pinions available from stock. See Table 5A.

RK Series (inch series) Bearing Selection DataStandard Tolerances

14 15

Pre-engineered turntablebearings from stockNow you can get a turntable bearingfor medium duty applications...FROMSTOCK. Kaydon’s RK-Series bearingsprovide a cost effective solution forapplications such as small cranes, booms,and lifts; aerial towers and ladders;industrial positioners and rotary tables;rotating displays; robotics; materialhandling equipment and conveyors.

Standard bolt holes make mountingeasy. Available in sizes up to 48" O.D.with internal gear, external gear, andnon-geared configurations. For momentloads to 140,000 ft.-lbs. Matchingpinions also from stock.

★ Warning–Damage to equipment and danger to human life can result from failure to heed therecommendations in the text identified by the warning symbol. See load rating charts on page 23.

Table 5—External geared RK Series (Figure 14)

Outline dimensions (inches) Mounting holes Gear data—20° stub involuteModel Kaydon Weight

OD LO LI CI ID BCONo. holes

BCINo. holes

PDDiametral No. Max. tangential Circle toothnumber P/N lbs.

BCO BCI pitch teeth tooth load (lbs.) thicknessRK6-16E1Z 39550001 72 19.900 16.220 16.140 14.490 11.970 18.000 8 13.130 12 19.500 4 78 5550 .3877/.3777RK6-22E1Z 39551001 96 25.150 21.340 21.260 19.610 17.090 23.250 12 18.130 15 24.750 4 99 5650 .3877/.3777RK6-25E1Z 39552001 115 29.150 25.280 25.200 23.550 21.030 27.250 15 22.130 18 28.750 4 115 5690 .3877/.3777RK6-29E1Z 39553001 128 32.900 29.220 29.140 27.490 24.970 31.000 18 26.130 18 32.500 4 130 5760 .3877/.3777RK6-33E1Z 39554001 152 37.200 33.150 33.070 31.420 28.900 35.000 18 30.000 18 36.667 3 110 7590 .5186/.5086RK6-37E1Z 39555001 172 41.200 37.090 37.010 35.360 32.840 38.880 18 34.000 20 40.667 3 122 7640 .5186/.5086RK6-43E1Z 39556001 189 46.867 43.000 42.920 41.270 38.750 44.630 20 39.880 24 46.333 3 139 7680 .5186/.5086

Tolerances +.000 Ref. Ref. +.080 ±.040-.030 -.000

Table 3—Non geared RK Series (Figure 12)

Outline dimensions (inches) Mounting holesModel Kaydon Weight

OD CO LO LI CI ID BCONo. holes

BCINo. holesnumber P/N lbs.

BCO BCIRK6-16P1Z 39510001 58 20.390 17.870 16.220 16.140 14.490 11.970 19.250 8 13.130 12RK6-22P1Z 39511001 76 25.510 22.990 21.340 21.260 19.610 17.090 24.380 12 18.130 15RK6-25P1Z 39512001 89 29.450 26.930 25.280 25.200 23.550 21.030 28.380 12 22.130 18RK6-29P1Z 39513001 104 33.390 30.870 29.220 29.140 27.490 24.970 32.250 15 26.130 18RK6-33P1Z 39514001 118 37.320 34.800 33.150 33.070 31.420 28.900 36.250 18 30.000 18RK6-37P1Z 39515001 132 41.260 38.740 37.090 37.010 35.360 32.840 40.130 18 34.000 20RK6-43P1Z 39516001 153 47.170 44.650 43.000 42.920 41.270 38.750 46.000 18 39.880 24

Tolerances ±.040 +.000 Ref. Ref. +.080 ±.040-.080 -.000

Table 4—Internal geared RK Series (Figure 13)

Outline dimensions (inches) Mounting holes Gear data—20° stub involuteModel Kaydon Weight

OD CO LO LI ID BCONo. holes

BCINo. holes

PDDiametral No. Max. tangential Circle toothnumber P/N lbs.

BCO BCI pitch teeth tooth load (lbs.) thicknessRK6-16N1Z 39530001 65 20.390 17.870 16.220 16.140 12.850 19.250 8 14.880 12 13.250 4 53 6810 .3877/.3777RK6-22N1Z 39531001 90 25.510 22.990 21.340 21.260 17.600 24.380 10 19.630 15 18.000 4 72 6460 .3877/.3777RK6-25N1Z 39532001 106 29.450 26.930 25.280 25.200 21.600 28.380 12 23.630 18 22.000 4 88 6430 .3877/.3777RK6-29N1Z 39533001 121 33.390 30.870 29.220 29.140 25.600 32.250 15 27.630 18 26.000 4 104 6320 .3877/.3777RK6-33N1Z 39534001 148 37.320 34.800 33.150 33.070 29.133 36.250 18 31.500 18 29.667 3 89 8520 .5186/.5086RK6-37N1Z 39535001 165 41.260 38.740 37.090 37.010 33.133 40.130 18 35.500 20 33.667 3 101 8440 .5186/.5086RK6-43N1Z 39536001 188 47.170 44.650 43.000 42.920 39.133 46.000 18 41.500 24 39.667 3 119 8340 .5186/.5086

Tolerances ±.040 +.000 Ref. Ref. +.030-.080 -.000

Figure 12

1.811 ref

.470

Inside dia. (ID)

.090 max. rad.

±040

Inner bolt circle (BCI)Inside land (LI)

Outer circle (CO)

.688 dia. throughequally spaced

Inner circle (CI)Outside land (LO)

Outer bolt circle (BCO)Outside diameter (OD)

.090 max. rad.

.470±040

1.102ref

1.811ref

2.205±040


Figure 13

1.811 ref

Gear inside dia. (ID)Gear pitch dia. (PD)


.500-13 UNC-2B

.750 min. full thread depth equally spaced

Outside land (LO)Outer bolt circle (BCO)

Outside diameter (OD)

.090 max. rad.

.470±040

1.811ref

2.205±040


Outer circle (CO)

.708 ref

Figure 14

1.811ref

Gear pitch dia. (PD)Gear outside dia. (OD)


.500-13 UNC-2B

.750 min. full thread depth equally spaced

Outside land (LO)

.090 max. rad.

.470±040

1.103ref


1.811ref

2.205±040

Inner circle (CI)

Outer bolt circle (BCO)

Inside dia. (ID)

Table 5A—Mating Pinions for RK-Series Bearings (Figure 15)

No. HubBearing Pinion of Diametral Face length Pitch Outer Hub Stocknumber number teeth pitch (F) (L) dia. dia. dia. bore

RK-6-16 thru 39200001 14 4 2.000 .88 3.500 3.900 2.880 1.000RK6-29 39200002 17 4 2.000 .88 4.250 4.650 3.630 1.000

RK-6-33 thru 39200003 14 3 2.000 .88 4.667 5.200 3.880 1.250RK6-43 39200004 17 3 2.000 .88 5.667 6.200 4.880 1.250

Tolerances Ref. Ref. Ref. Ref. +.000 Ref. +.002-.000 -.000

HubDia.Bore

L

F

O.D.P.D.

Figure 15

Custom Four-Point ContactBearing Selection Data

16 17

The unique “Gothic Arch” racewaydesign of four-point contact ball bear-ings provides an exceptional means ofhandling combined axial, radial andmoment loading. The applications forthese bearings are unlimited, rangingfrom heavy-duty cranes to machine toolturntables to advanced medical imagingequipment. Kaydon bearings have beenmanufactured with up to 10 millionpounds-feet of moment load capacity.

Listed below is a sampling of the manycustom-designed four-point contact ballbearings produced by Kaydon. One ofthese bearings may offer a pre-engineereddesign solution to your specific applica-tion requirements.

Many other custom designs are available.Through preloading and close tolerancemachining, extreme high precisionlevels can be maintained for these large-diameter bearings. Kaydon engineerswill be happy to review your applicationand make specific design recommenda-tions.

Table 6—Non geared four-point (Figure 16)

Outline dimensions (inches) Hole data ReferenceModel Kaydon No. No. Approx. moment

no. P/N OD ID W TO TI DI DO BCO holes HO BCI holes HI wt. load ratingouter inner ft.-lbs.

T4-13P1 12062 15.790 9.170 1.580 1.228 1.228 13.64 11.79 14.880 8 .562 10.250 8 .562 20 4,300

Table 7—Internal geared four-point (Figure 17)

Outline dimensions (inches) Hole data Gear data—20° U.S.A. std. stub ReferenceModel Kaydon No. No. BHN Tangential Approx. moment

no. P/N OD ID W TO TI CI BCO holes HO BCI holes HI PD DP FWNo. core toothload wt. ft.-lbs.

outer inner teeth hardness lbs. max. ratingT10-46N4 12496 51.120 39.760 3.560 3.120 2.690 41.620 49.125 24 1.063 43.000 20 1-8* 40.400 2.5 2.590 101 241-285 19,890 602 515,180T14-49N1 12131 54.375 41.280 5.000 3.875 4.625 43.000 52.500 22 .938 45.250 36 .938 41.600 2.5 3.000 104 262-302 25,030 1,090 837,000T20-95N1 09722 102.500 85.360 7.440 6.780 5.660 88.380 99.803 16 1.313 91.142 48 1.313 86.633 1.5 5.500 136 277-321 77,640 3,755 3,450,000

Table 8—External geared four-point (Figure 18)

Outline dimensions (inches) Hole data Gear data—20° U.S.A. std. stub ReferenceModel Kaydon No. No. BHN Tangential Approx. moment

no. P/N OD ID W TO TI CO BCO holes HO BCI holes HI PD DP FWNo. core tooth load wt. ft.-lbs.

outer inner teeth hardness lbs. max. ratingT8-39E4 12246 42.640 35.157 3.234 2.905 2.875 41.024 39.960 30 5/8-11 36.300 30 .687 42.000 2.5 2.593 105 262-302 19,455 301 270,000T10-20E2 12134 25.650 16.250 3.500 3.250 2.875 — 23.250 18 .781 17.625 20 .781 25.250 4 3.250 101 262-302 15,210 236 162,000T10-24E1 12343 30.171 18.875 3.500 3.188 2.625 — 27.625 36 .781 20.750 22 .781 29.714 3.5 3.188 104 262-302 17,085 301 238,730T14-18E2 11457 23.650 12.880 3.440 3.190 3.190 — 21.250 18 3/4-16 14.375 23 3/4-16* 23.250 4/5*** 3.190 93 250-300 14,545 260 214,670T14-22E4 12037 28.400 17.130 3.440 3.190 3.190 — 25.380 18 .781 18.630 23 .906 28.000 4 3.190 112 250-300 15,015 319 255,000T14-24E6 12070 29.887 19.125 3.625 3.250 3.250 — 27.375 30 3/4-10 20.625 29 .938 29.429 3.5 3.250 103 262-302 17,420 330 365,360T18-44E1 11736 52.800 36.950 4.750 4.375 4.375 50.655 48.250 30 1.313 39.375 30 1-1/4-7** 52.000 2 3.250 104 250-300 30,480 1,070 1,338,000T24-65E1 11729 74.800 55.875 6.375 6.000 6.000 72.625 70.250 45 1.313 58.500 47 1-1/4-7** 74.000 2 4.000 148 277-321 41,440 2,700 3,282,000T24-65E4 11311 75.800 53.875 6.500 6.000 6.000 66.990 70.250 52 1-1/2-6 58.500 51 1.566 75.000 2 3.750 150 277-321 38,850 3,075 3,526,000T24-89E2 11930 98.800 78.400 6.625 6.000 6.000 98.000 94.250 72 1-1/2-6 82.500 60 1.813 98.000 2 4.750 196 277-321 45,960 3,995 4,959,000T24-75E3 12198 85.067 66.750 7.120 6.500 6.620 82.120 80.125 30 1.313 69.250 32 1.313 84.000 1.5 6.000 126 277-321 81,920 3,409 2,773,000T24-89E1 11277 98.800 78.400 6.625 6.000 6.000 98.000 94.250 72 1-1/2-6 82.500 60 1.562 98.000 2 4.750 196 277-321 50,730 4,025 4,975,000

*UNF **UNC***Fellow stub★ Warning–Damage to equipment and danger to human life can result from failure to heed therecommendations in the text identified by the warning symbol.

Figure 18

Figure 17

Figure 16

W

ID

TO

TIFW

PD

BCIBCO

OD

HI

HO

CI

TO

ID

FW WTI

PD

BCI

BCO

OD

HO

HI

CO

ID

TI WTO

BCI

BCOOD

DI

DO


Eight-Point Contact BearingSelection Guide

18 19

Kaydon developed the eight-point con-tact ball bearing to provide increasedload capacity within prescribed diame-tral space limitations. These bearingsfunction as two four-point contactbearings mounted together and providemoment load capacities up to 15 millionpounds-feet.

In addition to the bearings shown below,we can customize a design to fill yourspecific requirements.

WireX® Bearing Selection Guide

Kaydon WireX® bearings were originallyapplied in military turret applications,where space and weight are at a premiumand corrosion resistance is essential.These bearings are typically producedusing stainless steel rolling elements andaluminum raceways.

WireX® bearings may also be used inturntable, radar and machine tool appli-cations. They may have up to 3 rows ofrollers and can provide moment loadcapacities up to 2.5 million pound-feet.

Table 9—Internal geared eight-point (Figure 19)

Outline dimensions (inches) Hole data Gear data—20° pressure angle ReferenceModel Kaydon No. No. BHN Tangential Approx. moment

no. P/N OD ID W TO TI BCO holes HO BCI holes HI PD DP FWNo. core tooth load wt. lbs. load

outer inner teeth hardness lbs. max. ft.-lbs.D14-98N1 12282 108.000 87.170 7.563 7.188 6.250 102.953 66 1.593 93.504 66 1.593 87.874 1.411* 4.130 124 277-321 73,760 5,170 6,900,000D20-111N1 11563 121.000 98.400 8.750 8.438 8.438 117.000 53 1.575 105.000 72 1.575 100.000 1.25* 6.000 125 277-321 107,130 7,610 14,000,000

Table 10—External geared eight-point (Figure 20)

Outline dimensions (inches) Hole data Gear data—20° pressure angle ReferenceModel Kaydon No. No. BHN Tangential Approx. moment

no. P/N OD ID W TO TI BCO holes HO BCI holes HI PD DP FWNo. core tooth load wt. lbs. load

outer inner teeth hardness lbs. max. ft.-lbs.D18-89E1 11943 98.800 78.400 8.875 8.250 8.250 94.250 72 1-3/4-8 82.500 60 1.812 98.000 2 4.750 196 277-321 49,680 5,580 7,900,000

*Special tooth form

Table 11—Internal geared WireX® (Figures 21 and 22)

Outline dimensions (inches) Hole data Gear data—20° pressure angleKaydon No. No. Approx.

P/NFigure

OD ID W TO TI CI BCO holes HO BCI holes HI PD DP FWNo. Ring wt. lbs.

outer inner teeth material

12321 21 41.000 34.079 1.629 1.306 1.569 36.705 40.000 30 .420 35.750 12 3/4-16 34.200 10/12*** .750 342 Steel 10511960 20 44.752 34.960 2.559 2.440 2.000 35.906 42.625 48 .687 37.375 64 .687 35.200 5* 2.000 176 Alum. 15011666 20 65.430 58.336 2.880 2.303 2.750 58.900 64.375 50 .530 61.250 48 1/2-20 58.500 10** 1.500 585 Alum. 31011830 20 67.360 59.775 2.953 2.640 2.441 60.620 66.000 48 .575 61.750 48 1/2-13 60.000 8** 1.939 480 Alum. 182

*Full depth **Special form***Fellows stub

★ Warning–Damage to equipment and danger to human life can result from failure to heed therecommendations in the text identified by the warning symbol.

Table 12—External geared WireX® (Figure 23)

Outline dimensions (inches) Hole data Gear data—20° pressure angleKaydon No. No. Approx.

P/NFigure

OD ID TO TI BCO holes HO BCI holes HI PD DP FWNo. Ring wt. lbs.

outer inner teeth material

13436 22 88.464 74.568 3.150 3.854 84.724 36 M24 77.205 29 1.024 88.189 3.629* 3.150 320 Alum. 615*Module #7 involute tooth form

Figure 19

Figure 20

Figure 21

Figure 22

Figure 23

TO

ID

FW WTI

PDBCI

BCOOD

TO

ID

FW

WTI

PD

BCI

BCOOD

HI

HO

W

ID

TO

TIFW

PDBCIBCO

OD

HI

HO

CI

W

ID

TOTI

FW

PD

BCI

BCOOD

HI

HOCI

TO

ID

TI

BCI

BCO

OD

HO


20

KH Series Pre-engineered highprecision bearing assemblies

Figure 24 Figure 25

Gear pitch dia. (G.P.D.)External gear (G.O.D.)

±.050

Land (P.L.I.) 500-13 UNC-2B.750 min. fullthread depth

I.D.

1.250 ref.

±.0302.000

Bolt circle (B.C.I.)Ref. ball pitch (P.D.)

Land (P.L.O.)Bolt circle (B.C.O.)

±.050O.D.

500-13 UNC-2B.750 min. fullthread depth

±.0302.000

.250 min. pilot depth

±.0102.500

Outline dimensional data (inches) Land diameters Hole data No. Approx.Model

PD ID OD PLI PLO No. holes No. holes BCI BCOlube assembly

inner outer holes weightKH166P 16.6 12.750 20.500 16.375 16.875 20 20 14.375 18.875 1 106KH225P 22.5 18.500 26.700 22.250 22.750 18 18 20.500 24.500 1 150KH275P 27.5 23.500 31.700 27.250 27.750 24 24 25.500 29.500 1 185

Table 14—Non geared KH Series (Figure 24)

Optional full depth involute gear 6 D.P., 20° pressure angle AGMA quality 8Model

G.O.D. G.P.D.No. of Circular tooth Allowance Approx. assembly

no. teeth thickness for backlash weightKH166E 20.500 20.167 121 .2618/.2568 .000-.005 100KH225E 26.667 26.333 158 .2618/.2568 .000-.005 142KH275E 31.667 31.333 188 .2618/.2568 .000-.005 175

Table 15—Geared KH Series (Figure 25)

Dynamic IntermittentSize Axial Moment Axial Moment

(lbs.) (lbs-ft.) (lbs.) (lbs-ft.)KH166 36,000 20,500 82,850 45,250KH225 40,000 30,500 115,200 56,000KH275 43,000 39,600 142,000 75,050

Table 15A—Designed for both dynamic and intermittent loads

Note:Dynamic-L10 capabilities based on million revolutions. Values do not applysimultaneously.Intermittent-Individual capacity limits for maximum loading when normalmode of operation is an intermittent load application and rotation.

KH Series bearings are designed to pro-vide precise positioning and stopping,with consistent repeatability, in applica-tions where rotation is constant, inter-mittent or oscillating. They are theideal bearing for advanced rotary indextables or any design where the bearingwill interface with other precisionmechanical components.

The KH Series bearing’s unique 4-pointcontact ball geometry enables one bear-ing to handle simultaneous radial, axial

and moment loading. An internal dia-metral preload provides greater stiffnessand minimum free play. And unlikeconventional air bearings, Kaydon KHSeries will not lock up in the presenceof off-center loads.

Available in 3 popular pitch diameters,in geared and non-geared versions,Series KH bearings feature a low profileto permit larger work areas above theindex table.

21

Tight deflection and tilttolerances give KH Seriesbearings their precisionKH Series bearings are often used inapplications where the position of arotating part relative to the stationarystructure is critical. The axis of rotationcan be displaced from its true position inthree ways-radially, axially, and angu-larly. These deviations are referred to asradial deflection, axial deflection, andtilt (angular rotation).

The following three tables show stiffnessof standard KH Series bearings. If yourapplication requires increased stiffness,Kaydon can often supply a stiffer bearingin the same envelope dimensions. Callus at (800) 514-3066.

0.0014

0.0012

0.0010

0.0008

0.0006

0.0004

0.0002

0

Rad

ial D

efle

ctio

n (i

n.)

Radial Loads (lbs.)0 1000 2000 3000 4000 5000 6000 7000 8000

KH166KH225KH275

.0007

.0006

.0005

.0004

.0003

.0002

.0001

.0000

Moment Loads (in.-lbs.)0 5,0000 100,000 150,000 200,000 250,000 300,000 350,000 400,000 450,000

KH166KH225KH275

Tilt

of A

xis (

radi

ans)

.0040

.0035

.0030

.0025

.0020

.0015

.0010

.0005

.0000

Axi

al D

efle

ctio

n (i

n.)

Axial Loads (lbs.)0 10,000 20,000 30,000 40,000 50,000 60,000

KH166KH225KH275

Materials of constructionand technical dataRolling elements–Chrome steel hardened to RockwellC 60 minimum.

Ball paths (raceways)–Selectively hardened for maximumobtainable bearing capacity. Four-point internal design permits accep-tance of combination axial, radial,and moment loads.

Geared and ungeared rings–Rolled high carbon steel forgingsquenched and tempered to 262BHN minimum

Gears–Involute Stub, 20° pressure angle,AGMA 8 quality

Seals–Nitrile rubber seals provide positivecontact for retention of lubricationand exclusion of contaminants

Lubrication–Multi-purpose lithium-based, NLGI No. 1 E.P. grease

Figure 25A—Radial Deflection

Figure 25C—Tilt of Axis

Figure 25B—Axial Deflection

22

Special Bearing Capabilities

In addition to the more standard bear-ings shown on the preceding pages,Kaydon has extensive experience in thedesign and manufacture of customized orspecial bearings and assemblies. The balland roller bearings shown below are onlya sampling of our custom capabilities.

Biangular roller bearings generally pro-vide higher stiffness and lower turningtorques than four-point contact ballbearings with equivalent load capacitiesor dimensional envelopes.

Figure 27The standard biangular bearing has beenapplied in a variety of wind energy, radar andmilitary turret applications.

Figure 30This aluminum race bearing with nonmetallicballs was originally developed to provide lightweight and corrosion resistance in a lightly load-ed military turret. Similar bearings are used inmedical equipment applications where theenvironment does not allow for grease lubrica-tion. A wide variety of ball materials can beused.

Figure 28The lightweight biangular bearing is made fromsteel and was originally designed for use as aturret bearing on a steel-hulled military vehicle.

Figure 31This three-row roller bearing is used on a largecrane slewing ring and provides a high degree ofstiffness, generally interchangeable with aneight-point contact ball bearing.

Figure 29The WireX® single-row biangular bearing shownprovides a larger rolling element—and resultanthigher load capacity—than a two-row WireX®

bearing with the same cross-selectional area. Aswith the bearings shown on Pages 18-19, thealuminum races and stainless rollers and wiresprovide light weight and corrosion resistance.

Figure 32This military turret bearing is a thin-sectionlarge diameter bearing with custom optionssuch as flanges and internal gears cut on theouter race. By adding these options to thebearing, a number of individual parts can beeliminated, simplifying assembly and resultingin lower total system cost.

5.000

78.00082.667

84.00068.000

64.500

6.0004.500

.625

61.25055.000

62.500

1.9382.000

57.000

.900

2.559

42.62544.752

2.4402.000

2.390

34.96037.375

1.629

40.00041.000

1.265.750 .939

35.75036.690

34.20034.079

1.569 9.563

149.500161.750

164.750144.000142.400

8.196

8.500 3.688

108.000109.500

106.250

103.750

4.562

1.406

100.640101.000

103.000

3.031

102.448100.500

Load Rating Charts

23

Axi

al lo

ad (

lbs.

x 1,

000,

000)

.4

.3

.2

.1

050 10 15 20

Moment load (ft.-lbs. x 10,000)

A B C D E F G H I

A–MT-145B–MT-145XC–MT-210D–MT-210XE–MT-265

LegendF–MT-265XG–MT-324H–MT-325I –MT-415

Axi

al lo

ad (

lbs.

x 1,

000,

000)

1.6

1.2

.8

.4

010 5 8 10


J K L

J–MT-470K–MT-540L–MT-590

LegendM–MT-705N–MT-730O–MT-870

1.51.41.3

1.11.0.9

.7

.6

.5

.3

.2

.1

2 3 4 6 7 9

M N O

MT-Series ratings apply to either MTE or MTO Series

Axi

al lo

ad (

lbs.

x 10

00)

200

150

100

50

0200 40 60 80

Moment load (ft.-lbs. x 1000)

A B C D E F G

A–RK6-16B–RK6-22C–RK6-25D–RK6-29

LegendE–RK6-33F–RK6-37G–RK6-43

100 120 140

Axi

al lo

ad (

lbs.

x 1,

000,

000)

4.0

3.0

2.0

1.0

050 25 40 50


A B C

A–T10-46B–T14-49C–T20-95

Legend

10 15 20 30 35 45

3.5

2.5

1.5

0.5

Internal gear4-point contact

Figure 33 Figure 34

Figure 35 Figure 36

RK-Series

24

Axi

al lo

ad (

lbs.

x 1,

000,

000)

.80

.60

.40

.20

00


C

A–T10-20B–T14-18C–T10-24

LegendD–T14-22E–T8-39

.75

.70

.65

.55

.50

.45

.35

.30

.25

.15

.10

.05 DE

5 25 40 5010 15 20 30 35 45

BA

External gear4-point contact

Axi

al lo

ad (

lbs.

x 1,

000,

000)

4.0

3.0

2.0

1.0

050 25 40 50


A B C

10 15 20 30 35 45

3.5

2.5

1.5

0.5

A–T14-24B–T18-44C–T24-75

LegendD–T24-65E1E–T24-65E5F–T24-89

D E F

External gear4-point contact

Axi

al lo

ad (

lbs.

x 1,

000,

000)

8.0

6.0

4.0

2.0

020 10 16 20

Moment load (ft.-lbs. x 1,000,000)

A B C

A–D14-98B–D18-89C–D20-111

Legend

4 6 8 12 14 18

7.0

5.0

3.0

1.0

8-point contact

Figure 37 Figure 38

Figure 39

Part I—DesignConsiderations (ForGuidance of theEquipment Designer)

Mounting structureMost designs are necessarily a compro-mise from the ideal to the practical. Thedesign of mountings for large multiloadbearings is no exception. Several con-ditions, however, must be satisfied by themounting structures above and belowthe bearing, in order to give good bear-ing life and performance. These condi-tions are stiffness, flatness, hole locationaccuracy, protection, access for mainte-nance, and attachment method.

StiffnessThe ideal bearing mounting would beabsolutely rigid, but mobile equipmentis by its very nature flexible and thuselastic deflections will occur. However,distortions can be held to tolerable levelsif the shape of the main structuralmembers above and below the bearingare generally in the form of a cylinderwhose outer diameter is equal to orslightly larger than the bearing ring towhich they are attached. An example isthe flanged drums commonly used oncrawler trucks.

Figure 40 has been prepared to show themaximum allowable deflections ballbearings can withstand and still functionproperly. Deflection must be gradual.Avoid short, stiff sections in the mount-ing as these can adversely affect theloading pattern of the rolling elementsby causing extremely high loads betweena few elements and the raceways. Theyalso have a similarly adverse effect onbolt loads. In addition, excessive turningtorque may result, causing high geartooth loads.

Installation and Care ofKaydon Turntable Bearings

25

NOTE: These charts refer to ball bearings. For roller bearings, consult Kaydon for allowable stiffnessand flatness.

Allo

wab

le m

ount

ing

defle

ctio

n (i

n. in

90°

arc

)

.150

200 40 60Bearing pitch diameter (in.)

80 100 120 140 160 180

.130

.110

.090

.070

.050

.030

.0101” ball

1-1/2” ball

2” ball

2-1/2” ball

3” ball

3-1/2” ball

Allo

wab

le m

ount

ing

surf

ace

out-

of-f

latn

ess

(in.

in 9

0° a

rc)

200 40 60Bearing pitch diameter (in.)

80 100 120 140 160 180

.060

.050

.040

.030

.020

.010

2-1/2” ball

3-1/2” ball

0

3” ball

2” ball

1-1/2” ball

1” ball

Figure 40—Allowable mounting deflection (circumferential)

Figure 41—Allowable mounting out-of-flatness (circumferential)

26

FlatnessBearing mounting surfaces must bemachined flat after all welding and stressrelief treatment on the structures is com-plete. If subsequent welding is necessary,it must be done in such a manner thatno distortion is experienced by themachined mounting surface. The allow-able degree of out-of-flatness is shown inFigure 41. Out-of-flatness like distortion,must be gradual.

Questions are often asked about shim-ming or grouting of mounting surfaces tocompensate for excessive out-of-flatness.While shimming is acceptable if doneproperly, most equipment builders find itso difficult to control in production thatit is more troublesome and costly thanmachining. Plastic grout has such a lowmodulus of elasticity that under cyclicloading mounting bolt fatigue failurecan result. Thus, KAYDONSTRONGLY RECOMMENDSAGAINST THE USE OF GROUTINGWHEREVER CYCLIC THRUST ANDMOMENT LOADS ARE EXPECTED.

Another consideration is theallowable deviation from a true plane ina radial direction (“dish”), which ismore difficult to control in machiningmounting surfaces. Table 16 showsallowable values for out-of-flatness asmachined and for deflection under load.

Table 16

Allowable out-of-flatness anddeflection—radial (“dish”)

Out-of-flatness Deflection

Ball dia.inches per inches per

inchesradial inch of radial inch of

mounting mountingsurface surface

1 .0010 .00301-1/2 .0015 .0045

2 .0020 .00602-1/2 .0025 .0075

3 .0030 .0090

3-1/2 .0035 .0105

Hole location accuracy, pilotsMounting holes and dowel holes, if any,must be within the true location toler-ances required to prevent distortion ofthe bearing due to interference. See theapplicable drawing for the bearing toler-ances. Use of bearings as templates fortransfer of hole location is permissible ifcare is taken not to distort thin sectionbearings. But bearings should never beused as drill jigs.

Pilots, if used, must be round and accur-ately sized so that they do not distort thebearing. Mounting hole location toler-ance must include any eccentricity ofthe hole pattern with pilot diameters.

ProtectionIn general, Kaydon bearings are designedto withstand all normal operatingenvironments. However, if the upperstructure does not provide completecover for the upper bearing, a seal orshield should be added. Also, an externalgear that would be exposed to very dirtyconditions should be shrouded.

Shields and shrouds should be designedwith cover doors, plugs, or other meansof access to the bearing for the purposesdiscussed below.

Access for maintenanceLike all mechanical components on amachine, the bearing must be accessibleso that it can be properly maintained.The following must be considered.★ Mounting bolts require periodic check-ing and retightening. Access to everymounting bolt must be readily available,or this maintenance item will beneglected and may result in mountingbolt failure.

Lubrication of Gear and Raceway isrequired and therefore convenientaccess to the gear and bearing greasefittings must be provided. Convenienceis stressed because of the human elementinvolved. It is best to add remote linesto the bearing so that it may be rotatedas grease is introduced to the raceways.

The Taper Pin Retainer for the ballloading hole plug must be removed onrare occasions by qualified personnel toinspect raceways or to replace rollingelements or spacers. A hole, approxi-mately 11/4 inches in diameter must belocated in both upper and lower mount-ing structures directly above and belowthe “Taper Pin Retainer,” so that it maybe removed. (See Figure 42.)

★ AttachmentThe method of attachment of Kaydonbearings to the support structure signifi-cantly affects their design. The type,size, and quantity of fasteners must bedetermined if bolts will be used. If weld-ing is to be done, a decision must be madeas to which race will be so attached andwhether a “band” will be welded to theinner or outer diameter or a “ring” willbe welded to one of the faces.

★ BoltsThe preferred bolting arrangement is afull circle of equally spaced fasteners inthrough holes in both bearing races.This benefits both the bearing and thebolts. The bearing races are reinforcedby the bolt pretension. The greater boltlength makes for more accurate anduniform pretension.

Figure 42—Access holes forloading hole plug

★ For three important reasons responsi-bility for the quantity, size, and threadengagement of fasteners must beaccepted by the equipment designer.a. There is no universally accepted

method of analyzing the forcesimposed on the fasteners in a jointsubjected to moment loading.

b. The stiffness and uniformity of thestructures to which the bearing isattached have an extremely highdegree of influence on the load in thefasteners. Only the equipmentdesigner can control this.

c. The quality of the fasteners, themethod of pretensioning, the hardnessof the surfaces under the heads andthe thread lubricant are other impor-tant factors over which the equipmentmanufacturer has control.

★ This should be done with the adviceand assistance of the supplier of the boltsbecause the quality of bolts varies widelyas do the recommendations for methodsof pretensioning and maintenance ofpretension. Attention to such details asa head/body fillet radius, thread form, aswell as the more obvious freedom fromcracks and other possibly fatal flaws arevery important to the safety of theequipment. The importance of adequateand uniform pretensioning is evidentfrom the proliferation of and advances indevices offered for this purpose—rangingfrom turn of the nut indicator to preloadindicating washers to torque wrencheswith integral “yield” sensors to comput-erized torque wrenches to hydraulic boltstretchers.

★ At the least, Kaydon recommends theuse of high strength bolts with coarsethreads and hexagon heads, and heavyseries nuts of equivalent strength. Also,recommended is the use of thread lubri-cant and hardened steel flat, Belleville,or calibrated preload indicating washers.Use of lockwashers is NOT recom-mended when bolts are tensioned bytorquing, because of the danger of

27

undertensioning due to high frictiontorque.

For the protection of the equipmentbuilder, specifications should requirethat the bolts carry not only thestandard SAE grade code but also apositive means of identifying themanufacturer.

★ WeldingOf late, the attachment of bearings bywelding has been limited on new appli-cations to unusual situations. These arebest handled by working directly withthe Kaydon Engineering Department to

Bolt LoadingTo aid the designer, a method is presented here to calculate the approximate loadon the heaviest loaded bolt. This method is based upon past experience andyields results that have proved satisfactory for most applications. It is analogousto the method Kaydon uses to determine the load in the heaviest loaded rollingelement within a bearing.

However, for the reasons stated Kaydon makes no warranty, expressed orimplied, regarding the adequacy of the bolts. The only certain way to determinethe actual load is by testing, which is strongly recommended.

Bolt Load Factor of Safety

Rb = M x Ff ± Ft *Fs =

Bolt Proof Load Rating D x N N Rb

M = Moment load in pounds-inchesFf = Flexibility factor. Use 3 for bearings and support structures of average stiffnessFt = Axial load in lbs.D = Bolt circle dia. in inchesN = total number of equally spaced boltsRb = Total load on heaviest loaded bolt in lbs.*Fs = Factor of safety of bolts. Recommended minimum value 3

Bolt Proof LoadCoarse Thread Series

S.A.E. Grade #8 and ASTM A 490Proof Proof

Bolt Dia. Ins. Load Lbs. Bolt Dia. Ins. Load Lbs.1/2 ............................................ 17,000 1 .............................................. 72,7005/8 ............................................ 27,100 1-1/8 ....................................... 91,6003/4 ............................................ 40,100 1-1/4 ..................................... 116,3007/8 ............................................ 55,400 1-1/2 ..................................... 168,600

establish both the optimum design andthe best welding procedures.

GearsKaydon offers integral gears as eitherstraight or helical spur, and either inter-nal or external. Use of a 20° pressureangle is favored because of availability ofstandard cutters, but 14-1/2°, 25°, andspecial pressure angles can be furnished.

SelectionThe machine designer will usually deter-mine the tooth size and form, workingwithin the constraints of his applicationand basing his selection on his own


28

methods of calculation and past experi-ence. However, the commonly acceptedLewis equation may be used to determinethe size of the gear.L = SFY PL = Tangential Tooth LoadS = Allowable Bending StressY = Tooth Form Factor (Table 17)P = Diametral PitchF = Face Width

Allowable bending stress (S)

Allowable BendingCore Hardness Stress P.S.I.

241-285 BHN (23-30Rc) 34,000262-302 BHN (27-32Rc) 37,000277-321 BHN (29-34Rc) 40,000

The stresses given above are for maxi-mum or “Stall Torque” conditions. Whenshock factors are included in theloading, higher stresses may be used.

The “Stub” tooth form is often used inlarge gears. Economics is the mainreason this tooth form is selected. Itrequires less material in the ring forgingand less gear cutting time. The “FullDepth” tooth form provides a greatercontact ratio, and consequentlysmoother operation but lower bendingstrength.

Surface hardeningInduction hardened gear teeth, withminimum surface hardness of 55 Rcshould be considered when high toothsurface pressures constantly occur. Anexcavator or logger which sees a highrate of acceleration and a rapid decel-eration during a swing cycle would betypical of this condition.

A full root radius with root hardeningis recommended when gear teeth areinduction hardened. The tooth patternand depth of hardness are critical.

Table 18

Case depth-induction hardened gearsDiametral pitch Flank depth Root depth

4.00 .040 .0303.50 .050 .0353.00 .060 .0402.50 .075 .0502.00 .100 .0701.75 .125 .0801.50 .150 .100

Table 17

Tooth form factor (Y)No. 20° full 20°stub Internal gearsof depth involute tooth Fellows stub tooth system 20°full depth

teeth system system 4/5 5/7 6/8 system12 .245 .311 .301 .349 .32013 .261 .324 .317 .361 .33614 .276 .339 .330 .374 .35215 .289 .348 .339 .386 .36116 .295 .361 .349 .396 .37417 .302 .367 .358 .405 .38318 .308 .377 .367 .411 .38919 .314 .386 .374 .412 .39920 .320 .393 .380 .424 .40521 .327 .399 .386 .430 .41122 .330 .405 .393 .437 .41224 .336 .415 .402 .446 .42726 .346 .424 .408 .455 .43728 .352 .430 .418 .462 .443 .69130 .358 .437 .424 .468 .449 .67834 .371 .446 .437 .480 .461 .66038 .383 .456 .440 .484 .468 .64443 .396 .462 .452 .446 .480 .62850 .408 .474 .462 .506 .490 .61360 .421 .484 .471 .515 .499 .59775 .434 .496 .484 .525 .509 .581

100 .446 .506 .496 .537 .521 .565150 .459 .518 .509 .547 .534 .550300 .471 .534 .525 .563 .550 .534

Use in Lewis Formula for P_________ 4 5 6

Therefore, a high degree of quality con-trol must be exercised to assure that theproper pattern is maintained, and thatcracks are non-existent. Some typicaldepths of hardness are as follows:

BacklashProper backlash must be provided in anypair of gears. This is especially true ofbearing gears, where large diameters andlarge center distances require greatermanufacturing tolerances. Therefore,the allowance for backlash must besufficient to allow for these greatertolerances. Typical backlash allowancesare shown in Table 19.

Other factors bear on the machinedesigner’s decision whether or not toprovide backlash by adjustment ofcenter distance between gear andpinion. But the cost advantages ofadjustment should be kept in mind.Gear size tolerance can be greater andlife can be extended by take-up for wear.

Storage before installationThere is no need for special care or lub-rication of Kaydon Turntable Bearingsbefore being put into service. They arepacked with general purpose grease atthe factory and are sealed to excludeordinary foreign matter. However, theyshould be kept in the shipping containerin a horizontal position until time forinstallation. Outdoor storage is notrecommended and if installation is notmade within a year, new grease shouldbe introduced.

External surfaces of turntable bearings,including the gear, are coated with apreservative oil to give them nominalprotection during storage.

29

InstallationInstallation of the bearing/gear assemblyshould be done in a clean, dry, well-lighted area. Mounting surfaces andpilots of the housings should be un-painted and wiped clean of chips, dirt,and lint, since even “soft” material whenentrapped will act as high spots. Whenthis has been done, examine for andremove weld spatter, nicks and burrs andwipe clean again. The bearing may nowbe unwrapped and lifted or hoisted intoposition. Use eye bolts in mountingholes or nonmetallic slings to avoiddamage to bearing mounting faces andpilots, and to gear teeth.

Inherent in the hardening process ofmost turntable bearings is a small gap atone point in the raceway. The loadinghole (see Page 26) is drilled through thisgap. The location in the mating race issteel stamped “G” on the seal face.Hardening gaps and load hole plugs inraces with through holes should bepositioned at minimum load points ifpossible. LOAD HOLE PLUGS INRACES WITH TAPPED HOLES ORWELD RINGS MUST BE SO POSI-TIONED. With the rotating race, thismay be done by placing the loading hole90° from the maximum load zone due tomoment loading. With the stationaryrace the position will depend upon thelocation of the lightest load relative tothe lower structure of the machine.

★ SAE Grade 8 or better boltsshould be used to ensureadequate bolt strengthFor good internal load distribution andsmooth, low torque operation, the bear-ing should be as round as possible whenthe bolts are tightened. If one of theraces is doweled or piloted, it should bemounted first whenever possible. Onunpiloted, gear bearings the gear/pinionbacklash should be checked and adjustedto the desired amount. The minimumbacklash point of the gear is identifiedby yellow paint in the tooth space. We


recommend the following procedure toassure trouble-free operation:• Leave all mounting bolts loose until

both mating parts are attached to thebearing.

• While applying a moderate centeredthrust load to the bearing, measure thetorque to rotate the bearing.

• Then tighten all bolts to the levelprescribed by the bolt manufacturer.THIS IS VERY IMPORTANT.Improperly tightened bolts can faildue to fatigue; such failure can causedamage to equipment and endangerhuman life.

• Again measure the torque required torotate the bearing.

• If greater than the first measurementthis indicates that the bearing is beingdistorted. Determine and correct thecause.

Gears on fixed centers may now bechecked for backlash, and pinions onadjustable centers set for proper back-lash.

When all backlash checks are com-pleted, the gear should be given acoating of grease suitable for theoperating conditions, and rotated toassure coverage of all contacting surfaceswith the pinions.

Complete installation of all rotatingcomponents of significant weight, andcheck bearing for freedom of rotation.Excessive torque level or variation isindicative of some unsatisfactoryinstallation condition.

Relubricate the bearing prior to ship-ment of the machine.

★ NOTE: For installation procedure forweld ring bearings contact your KaydonRepresentative or Kaydon factory.

MaintenanceWhile Kaydon turntable bearingsrequire almost no attention, what littlethey are given will pay big dividends in

Table 19

Gear Minimum Maximum Backlash (in.)Pitch Backlash Diametral PitchDia. (in.) 1.5 1.75 2 2.5 3,4,520 .014 .029 .027 .025 .023 .02230 .015 .030 .028 .026 .024 .02340 .016 .031 .029 .027 .025 .02460 .018 .033 .031 .029 .027 .02680 .020 .035 .033 .031 .029 .028100 .022 .037 .035 .033 .031 .030120 .024 .039 .037 .035 .033 .032

30


Part II—Installation(For Guidance of theEquipment Builder)Refer to Part I to determine that thedesigner has properly applied the bear-ing and made provision for properinstallation. But keep in mind that thebest design in the world can fail to liveup to its potential if the execution ofthe design by the builder is faulty.

Before installationRecognize the vital role of the bearing/gear and the fastening means (bolts orwelds).

Prepare detailed and clear instructionsto the tradesmen. If bolts are to be usedas the means of attachment, conductnecessary tests to prove the method ofpretensioning. Check to see that thebolts carry not only the standard SAEgrade code but also a positive means ofidentifying the manufacturer. The codefor SAE Grade 8 is 6 radial lines on thetop of the hex head.

If the bearing is to be attached by weld-ing, conduct the necessary tests to provethat the specified joint will be developedby the intended method.

Provide a clean, dry, well-lighted areafor performance of the installation work.

Keep the bearing wrapped in its originalwrapping until all preparations havebeen made for its installation.

When handling individual bearings useeye bolts in mounting holes. If the bear-ing must be turned over or slings areused for other reasons, use nylon webslings or equivalent to avoid damagingthe bearing mounting surfaces, the gear,or the seals. Do not use chains ormetallic mesh slings in contact with thebearing!

During installationWipe equipment mounting surfaces andpilots clean of chips, dirt, and lint. Even“soft” material when entrapped will actas high spots.

Examine for and remove weld spatters,nicks, and burrs. If surfaces have beenpainted, remove completely. Unpackagethe bearing; wipe free of all foreignmatter; visually inspect for damage inshipping.

Recheck bolt tightness. The reason forany loss of pretensioning must be deter-mined and eliminated.

If equipment is not delivered immedi-ately, introduce fresh grease into thebearing until grease can be seen exudingfrom seals. Move bearing in rotationseveral times to ensure a complete fill.Repeat every 6 months on idle equip-ment.

Remove any minor burrs from mountingsurfaces caused in shipping or handling.Use a hand file, taking care to removeonly as much material as necessary toinsure full contact of bearing surfacewith equipment mounting surface. DONOT DISASSEMBLE BEARINGwithout express approval of and instruc-tion from Kaydon. Removal of loadinghole plug voids our warranty.

Wipe bearing and equipment mountingand pilot surfaces clean once more.

Lift bearing into position for installa-tion. Rotate races to align loading holeplug (in ungeared race) and stamped“G” (on gear race) in accordance withyour designer instructions.

Install bearing in manner and sequenceprescribed by your designer paying par-ticular attention to the gear mesh, tofree entry of bolts into bolt holes, to thebolt pretensioning, and to changes inbearing torque. Determine reason forand eliminate any problems with any ofthese items before proceeding. Do not

long life, high performance, andtrouble-free service.

Relubrication of the bearing is recom-mended every 100 operating hours forrelatively slow rotating or oscillatingapplications such as backhoes, excava-tors, and cranes. In more rapidly movingor continuously rotating machinery suchas trenchers, borers, and distributors thebearing should be lubricated every day,or every 8 hours if on round-the -clockservice.

Idle equipment should not be neglected.Grease dries out and “breathing” due totemperature changes, can cause conden-sation within the bearing. Whether usedor not, the bearing should have greaseintroduced every 6 months. It is alwaysa good idea to rotate the bearing a fewturns to coat all surfaces with freshgrease.

There is a tendency to take much bettercare of the bearing than of the gear. Thismay be due to the rather crude gearsused in the past. The meshing actionand usual position of the gear tends topurge the lubricant; thus, the gearshould be regreased frequently with asmall amount of lubricant. The gear isdeserving of good care and will returnthe favor in long, smooth quiet service.It is recommended that grease beintroduced at the point of mesh ofpinion and gear every 8 hours of slow orintermittent operation, and more oftenfor rapidly or continuously rotatingapplications.

The cyclic nature of the loading on themounting bolts gives rise to the possibil-ity of their working loose or to inelasticdeformation of the threads and otherstressed surfaces. Bolts should bechecked periodically and retightened tothe proper level.★ THIS IS A VERY IMPORTANTSAFETY PRECAUTION.

31

Part III - Use & Care (ForGuidance of EquipmentOwner and/or User)While Kaydon Turntable Bearingsrequire almost no attention, what littlethey are given will pay big dividends inlong life, high performance, andtrouble-free service.

Before UseIf you cannot be sure that the bearing/gear has been lubricated within the pastsix months or after 100 hours of opera-tion, introduce fresh grease in accor-dance with equipment manufacturer’sinstruction manual (owner’s manual).

★ During Use• Relubricate bearing and gear in

accordance with Owner’s Manual.• Inspect seals, making certain that they

are in proper position in grooves andintact.

• Retighten mounting bolts in accor-dance with Owner’s Manual. THISIS A VERY IMPORTANT PRECAUTION.

• Be alert to changes in torque, unusualsounds, vibrations.


distort the bearing to permit bolts toenter holes that do not line up. Weldinginstructions for attachment of weld-ringbearings must incorporate every detailincluding, but not limited to weldingrod, protective material and/or atmo-sphere, all machine settings, tackingprocedure, preheating, heating whilewelding, post-heating, number of passesand inspection procedures.

When all backlash checks are complete,the gear should be given a coating ofgrease suitable for the operating condi-tions and rotated to assure coverage ofall contacting surfaces with the pinions.

Complete installation of all rotatingcomponents of significant weight, andcheck bearing for freedom of rotation.Excessive torque level or variation isindicative of some unsatisfactoryinstallation condition.

★ After installationWhen equipment has been completelyassembled, and before testing, check bolttightness. The reason for loss of preten-sioning beyond a reasonable amount forseating of mounting surfaces and threadsmust be determined and eliminated.Conduct required tests.

★ Recheck bolt tightness. The reason forany loss of pretensioning must bedetermined and eliminated.

Relubricate the bearing prior to deliveryof the machine. Introduce fresh greaseinto the bearing until grease can be seenexuding from the seals. Move bearing inrotation several times to insure acomplete fill. Repeat every 6 months onidle equipment.

★ Kaydon recommends that the Owner’sManual prepared by the equipmentbuilder be submitted to the KaydonEngineering Department for review andapproval of the sections relating to thebearings and gears supplied by Kaydon.

32

Custom Bearing Application Data

Fax to us at 231-759-4102Please answer the questions on this form as completely as possible, include a drawing (or sketch)of the application if available. Be sure to show all parts and information relevant to the application.The data you supply is the basis for our recommendation. There’s no obligation on your part, of course.

To Kaydon Corporation Date:P.O. Box 688–Muskegon, Michigan 49443

From Name: Title:

Company: Telephone:

Address:

Application:

❑ Experimental ❑ Prototype ❑ Production ❑ Spec. Machine ❑ Other❑ Original Equipment Mfg. ❑ Replacement ❑ Own Use ❑ Resale

Annual Usage: Quotation Quantity:

LoadsCondition

Loads RPM Percent of

Axial Radial Moment Max. Mean Time123456789

10

Vibration or shock? Describe

Factor of Safety of (is) (is not) included in loads above.

Life Hours (Min.) Hours (Avg.) Other

Temperature Normal Operating °F Minimum °F Maximum °FDifferential between shaft and housing

Lubrication Proposed lubricant and method

Bearing Preferred Size: Bore Outside Dia. Width

Min. Bore Max. Outside Dia. Max. Width

Preferred Type:

Bearing Axis in (Vertical) (Horizontal) position with (Outer) (Inner) race rotation relative to load.

Gear Internal or External Tooth Form PD DP Face Width

Specialrequirements (Materials, Torque, Oscillating Motion, Accuracy Seals, Protective Coatings, etc.)

Date required

Comments:

33

Warranty

Seller warrants the products manufac-tured by it to be free from defects inmaterials and workmanship only. Theextent of Seller’s obligation hereunder isto either repair or replace its work or thedefective products, F.O.B. Seller’s plant,if returned within 12 months after dateof delivery. No allowance will be grant-ed for repairs or alterations made byBuyer without Seller’s written approval.The warranty shall not be construed tocover the cost of any work done byBuyer on material furnished by Seller orthe cost of removal or installation ofproduct. Products and parts not manu-factured by Seller are warranted only tothe extent and in the manner that thesame are warranted to Seller by Seller’svendors and then only to the extentSeller is able to enforce such warranty.There is no other warranty, express orimplied in fact or by law.

THE FOREGOING STATES THESOLE AND EXCLUSIVE WARRANTYOF BUYER AND THE SOLE ANDEXCLUSIVE WARRANTY OFSELLER. THE WARRANTIESSTATED IN THIS PARAGRAPHARE IN LIEU OF ALL OTHERWARRANTIES, WRITTEN ORVERBAL STATUTORY, EXPRESSEDOR IMPLIED, INCLUDING WAR-RANTIES OF MERCHANTABILITYAND FITNESS FOR A PARTICULARPURPOSE, WHICH ARE HEREBYDISCLAIMED.

Seller’s agreement to sell the products ismade upon the condition and agreementthat, with respect to the products, therehave been no representations or under-takings made by or on behalf of Sellerand Seller makes no guarantees orwarranties, expressed or implied, in factor in law, except as expressly statedabove.

ChangesKaydon reserves the right to changespecifications and other information(included) in Kaydon bulletins withoutnotice. We recommend that you contactyour District Sales Engineer or Kaydonto be sure the information you have iscurrent.

ErrorsAll information, data, and dimensiontables in this manual and Kaydonbulletins have been carefully compiledand thoroughly checked. However, noresponsibility for possible errors oromissions can be assumed.

Important NoticeBecause of possible danger to persons orproperty from accidents which may resultfrom the use of the products described inthis catalog, it is important that gooddesign practices and correct proceduresbe followed. The products must be usedin accordance with the engineeringinformation provided herein; and properinstallation, lubrication, maintenance,and periodic inspection must be assured.

It is strongly recommended that appro-priate instructions be incorporated inequipment manuals to assure safe opera-tion under all conditions. Proper guardsand other suitable safety devices or pro-cedures as may be desirable or as may bespecified in safety codes should beprovided, and are neither provided byKaydon nor are the responsibility ofKaydon.

The product capability statements andengineering specifications in this catalogsupersede those published in all priorproduct publications.

★ WARNING—Damage toequipment and danger tohuman life can result fromfailure to heed the recommen-dations in the text identifiedby the warning symbol.

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Because a Bearing ProblemNeeded Solving...

Kaydon Corporation—one of the world’s leadingproducers of specialized custom and precision bear-ings—was built on the challenges nobody else wouldtake. Many of Kaydon’s former “specials” havebecome standard, off the shelf bearings- essentialcomponents for a broad range of products, frommachine tool tables to transmissions to space vehicles.

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Printed in U.S.A., 05/00 Catalog No. 390

KAYDON CORPORATION2860 McCracken Street

2360 Highway 15 South

Muskegon, Michigan 49443 U.S.A.Sumter Industrial Complex

Sumter, South Carolina 29154 U.S.A.

To place an order: Phone: (800) 616-3279, Ext. 256 • Fax: (803) 506-6280Need Service Fast? For Design Assistance, call 1-800-514-3066 • Visit our website: www.turntablebearings.com

Contact us for a no-obligation design review

No matter what your design, we can assess your needs and recommendthe right bearing assembly to best meet your particular performancerequirement. Just call us at 1-800-514-3066 to get started.

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ISO 9001

Catalog 390

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