6000 en 00 08 Mounting and Dismounting

7/17/2019 6000 en 00 08 Mounting and Dismounting

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General information ................................................................................................ 258Where to mount ............................................................................................................................. 258Preparations for mounting and dismounting ............................................................................... 258Bearing handling ............................................................................................................................ 260

Mounting................................................................................................................ 261Mounting bearings with a cylindrical bore .................................................................................... 261Bearing adjustment ....................................................................................................................... 262Mounting bearings with a tapered bore ........................................................................................ 263Test running .................................................................................................................................... 267

Dismounting ........................................................................................................... 268Dismounting bearings with a cylindrical bore ............................................................................... 268Dismounting bearings with a tapered bore................................................................................... 270

Bearing storage ...................................................................................................... 273

Inspection and cleaning ........................................................................................... 273

Mounting and dismounting

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General information

To provide proper bearing performance andprevent premature failure, skill and cleanlinesswhen mounting ball and roller bearings are

necessary.As precision components, rolling bearings

should be handled carefully when mounting.It is also important to choose the correctmethod of mounting and to use the correcttools for the job. The comprehensive SKF rangeof maintenance products includes mechanicaland hydraulic tools and heating equipment aswell as other products for mounting and main-tenance. This full line of products will facilitateand speed the work, giving professional results.

Brief information can be found in the sectionMaintenance and lubrication products, startingon page 1069.

To realize maximum bearing service life,a bearing must be installed correctly whichoften is more difficult than it appears, especiallywhere large size bearings are concerned. To besure that bearings are mounted and maintainedproperly, SKF offers seminars and hands-ontraining courses as part of the SKF ReliabilitySystems concept. Installation and maintenance

assistance may also be available from your localSKF company.

The information provided in the followingsection is quite general and is intended pri-marily to indicate what must be considered bymachine and equipment designers in orderto facilitate bearing mounting and dismount-ing. More detailed descriptions of the actualmounting and dismounting procedures canbe found in the publication SKF BearingMaintenance Handbook which is availablethrough your local SKF representative onrequest, or online at www.skf.com/mount orwww.aptitudexchange.com.

Where to mount

Bearings should be installed in a dry, dust-freeroom away from metalworking or other machinesproducing swarf and dust. When bearings haveto be mounted in an unprotected area, which is

often the case with large bearings, steps needto be taken to protect the bearing and mountingposition from contamination by dust, dirt andmoisture until installation has been completed.This can be done by covering or wrapping bear-ings, machine components etc. with waxedpaper or foil.

Preparations for mountingand dismounting

Before mounting, all the necessary parts, tools,equipment and data need to be at hand. It is alsorecommended that any drawings or instructionsbe studied to determine the correct order inwhich to assemble the various components.

Housings, shafts, seals and other compon-ents of the bearing arrangement need to bechecked to make sure that they are clean, par-ticularly any threaded holes, leads or grooveswhere remnants of previous machining oper-ations might have collected. The unmachined

surfaces of cast housings need to be free of coresand and any burrs need to be removed.

The dimensional and form accuracy of allcomponents of the bearing arrangement needsto be checked. The bearings will only performsatisfactorily if the associated components havethe requisite accuracy and if the prescribed tol-erances are adhered to. The diameter of cylin-drical shaft and housing seatings are usuallychecked using a stirrup or internal gauge at twocross-sections and in four directions ( fig. 1).Tapered bearing seatings are checked using ringgauges, special taper gauges or sine bars.

It is advisable to keep a record of the meas-urements. When measuring it is important thatthe components being measured and the meas-uring instruments have approximately the sametemperature. This means that it is necessary toleave the components and measuring equip-ment together in the same place sufficientlylong for them to reach the same temperature.

This is particularly important where large bear-ings and their associated components, which arecorrespondingly large and heavy, are concerned.

The bearings need to be left in their originalpackages until immediately before mounting so

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that they will not be exposed to any contamin-ants, especially dirt. Normally, the preservativewith which new bearings are coated before leav-ing the factory does not need to be removed; it isonly necessary to wipe off the outside cylindrical

surface and bore. If, however, the bearing is tobe grease lubricated and used at very high orvery low temperatures, or if the grease is notcompatible with the preservative, it is necessaryto wash and carefully dry the bearing. This is toavoid any detrimental effect on the lubricatingproperties of the grease.

Bearings should be washed and dried beforemounting if there is a risk that they have becomecontaminated because of improper handling(damaged packaging etc.).

When taken from its original packaging, anybearing that is covered by a relatively thick,greasy layer of preservative should also bewashed and dried. This might be the case forsome large bearings with an outside diameterlarger than 420 mm. Suitable agents for washingrolling bearings include white spirit and paraffin.

Bearings that are supplied ready greasedand which have integral seals or shields on bothsides should not be washed before mounting.

Fig. 1

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Bearing handling

It is generally a good idea to use gloves as wellas carrying and lifting tools, which have beenspecially designed for mounting and dismount-ing bearings. This will save not only time and

money but the work will also be less tiring, lessrisky and less injurious to health.

For these reasons, the use of heat and oilresistant gloves is recommended when handlinghot or oily bearings. These gloves should havea durable outside and a soft non-allergenicinside, as, for example, SKF TMBA gloves.

Heated and/or larger or heavier bearingsoften cause problems because they cannot behandled in a safe and efficient manner by oneor two persons. Satisfactory arrangements for

carrying and lifting these bearings can be madeon site in a workshop. The bearing handlingtool TMMH from SKF ( fig. 2) is one sucharrangement, which solves most of the prob-lems and facilitates handling, mounting anddismounting bearings on shafts.

If large, heavy bearings are to be moved orheld in position using lifting tackle, they shouldnot be suspended at a single point, but a steelband or fabric belt should be used ( fig. 3).A spring between the hook of the lifting tackle

and the belt facilitates positioning the bearingwhen it is to be pushed onto a shaft.

To ease lifting, large bearings can be providedon request with threaded holes in the ring sidefaces to accommodate eye bolts. The hole sizeis limited by the ring thickness. It is thereforeonly permissible to lift the bearing itself or theindividual ring by the bolts. Make also sure thatthe eye bolts are only subjected to load in thedirection of the shank axis ( fig. 4). If the loadis to be applied at an angle, suitable adjustableattachments are required.

When mounting a large housing over a bear-ing that is already in position on a shaft it isadvisable to provide three-point suspension forthe housing, and for the length of one sling to beadjustable. This enables the housing bore to beexactly aligned with the bearing.

Fig. 3

Fig. 4

Fig. 2

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Mounting

Depending on the bearing type and size,mechanical, thermal or hydraulic methods areused for mounting. In all cases it is important

that the bearing rings, cages and rolling elem-ents or seals do not receive direct blows andthat the mounting force must never be directedthrough the rolling elements.

Some parts may be mounted with a loosefit. To avoid any fretting corrosion between themating surfaces, it is recommended to applya thin layer of SKF anti-fretting agent LGAF 3 E.

Mounting bearings with a cylindrical

boreWith non-separable bearings, the ring that is tohave the tighter fit should generally be mountedfirst. The seating surface should be lightly oiledwith thin oil before mounting.

Cold mountingIf the fit is not too tight, small bearings may bedriven into position by applying light hammerblows to a sleeve placed against the bearing ringface. The blows should be evenly distributed

around the ring to prevent the bearing fromtilting or skewing. The use of a mounting dollyinstead of a sleeve enables the mounting forceto be applied centrally ( fig. 5).

If a non-separable bearing is to be pressedonto the shaft and into the housing bore at thesame time, the mounting force has to be appliedequally to both rings and the abutment surfacesof the mounting tool must lie in the same plane.In this case a bearing fitting tool should be used,where an impact ring abuts the side faces of theinner and outer rings and the sleeve enablesthe mounting forces to be applied centrally( fig. 6).

With self-aligning bearings, the use of anintermediate mounting ring prevents the outerring from tilting and swivelling when the bearingwith shaft is introduced into the housing bore( fig. 7). It should be remembered that theballs of some sizes of self-aligning ball bearingsprotrude from the side faces of the bearing, so

that the intermediate mounting ring should berecessed in order not to damage the balls. Largenumbers of bearings are generally mountedusing mechanical or hydraulic presses.

Fig. 5

Fig. 6

Fig. 7

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With separable bearings, the inner ring canbe mounted independently of the outer ring,which simplifies mounting, particularly whereboth rings are to have an interference fit. Wheninstalling the shaft, with the inner ring already

in position, into the housing containing the outerring, make sure that they are correctly aligned toavoid scoring the raceways and rolling elements.When mounting cylindrical and needle rollerbearings with an inner ring without flanges ora flange at one side, SKF recommends usinga mounting sleeve ( fig. 8). The outside diam-eter of the sleeve should be equal to the race-way diameter F of the inner ring and should bemachined to a d10 tolerance.

Hot mountingIt is generally not possible to mount larger bear-ings in the cold state, as the force required tomount a bearing increases very considerablywith increasing bearing size. The bearings, theinner rings or the housings (e.g. hubs) aretherefore heated prior to mounting.

The requisite difference in temperaturebetween the bearing ring and shaft or housingdepends on the degree of interference and thediameter of the bearing seating. Bearings

should not be heated to more than 125 C asotherwise dimensional changes caused byalterations in the structure of the bearing ma-terial may occur. Bearings fitted with shields orseals should not be heated above 80 C becauseof their grease fill or seal material.

When heating bearings, local overheatingmust be avoided. To heat bearings evenly, SKFelectric induction heaters ( fig. 9) are recom-mended. If hotplates are used, the bearing mustbe turned over a number of times. Hotplatesshould not be used for heating sealed bearings

Bearing adjustment

The internal clearance of single row angularcontact ball bearings and taper roller bearingsis only established, in contrast to other radialbearings with cylindrical bore, when one bearing

is adjusted against a second bearing. Usuallythese bearings are arranged in pairs eitherback-to-back or face-to-face, and one bearingring is axially displaced until a given clearanceor preload is attained. The choice of clearance orpreload depends on the demands placed on theperformance of the bearing arrangement andon the operating conditions. Additional informa-tion about bearing preloads can be found inthe section Bearing preload, starting onpage206, so that the recommendations in the follow-

ing refer only to the adjustment of internal

Fig. 8

Fig. 9

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clearance in bearing arrangements with angularcontact ball bearings and taper roller bearings.

The appropriate value for the clearance to beobtained when mounting is determined by theconditions when the bearing is under load and

at the operating temperature. Depending onthe size and arrangement of the bearings, thematerials from which the shaft and housing aremade and the distance between the two bear-ings, the initial clearance obtained on mountingmay be smaller or larger in actual operation. If,for example, differential thermal expansion ofinner and outer rings will cause a reduction inclearance during operation, the initial clearancemust be sufficiently large so that distortion ofthe bearings and the detrimental consequences

of this are avoided.Since there is a definite relationship between

the radial and axial internal clearance of angularcontact ball bearings and taper roller bearings,it is sufficient to specify one value, generally theaxial internal clearance. This specified value isthen obtained, from a condition of zero clear-ance, by loosening or tightening a nut on theshaft or a threaded ring in the housing bore,or by inserting calibrated washers or shimsbetween one of the bearing rings and its abut-

ment. The actual methods used to adjust theclearance and measure the set clearance aredetermined by whether a few or many bearingsare to be mounted.

One method is to check the set axial clear-ance, for example, of a hub bearing arrange-ment, using a dial gauge attached to the hub( fig. 10). It is important when adjustingtaper roller bearings and measuring the clear-ance that the shaft, or housing, is turnedthrough several revolutions in both directions tobe sure that there is proper contact of the rollerends with the guide flange on the inner ring. Ifthe contact is not correct, the measured resultwill be inaccurate and the desired adjustmentwill not be achieved.

Mounting bearings with a tapered bore

For bearings having a tapered bore, inner ringsare always mounted with an interference fit. Thedegree of interference is not determined by thechosen shaft tolerance, as with bearings having

a cylindrical bore, but by how far the bearing isdriven up onto the tapered shaft seating, or ontothe adapter or withdrawal sleeve. As the bearingis driven up the tapered seating, its radial inter-nal clearance is reduced. This reduction can bemeasured to determine the degree of interfer-ence and the proper fit.

When mounting self-aligning ball bearings,CARB toroidal roller bearings, spherical rollerbearings, as well as high-precision cylindricalroller bearings with tapered bore, either the

reduction in radial internal clearance or the axialdrive-up onto the tapered seating is determinedand used as a measure of the degree of interfer-ence. Guideline values of clearance reduction andaxial drive-up are provided in the text precedingthe relevant product table sections.

Fig. 10

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Small bearingsSmall bearings may be driven up onto a taperedseating using a nut. In the case of adaptersleeves the sleeve nut is used. Small withdrawalsleeves may be driven into the bearing bore

using a nut. A hook or impact spanner can beused to tighten the nut. The seating surfaces ofthe shaft and sleeve should be lightly oiled withthin oil before mounting is started.

Medium and large sized bearingsFor larger bearings, considerably more force isrequired and

SKF hydraulic nuts should be used and/or the oil injection method should be employed.

In either case, the mounting process will beconsiderably easier. The oil injection equipmentrequired for both, operating the hydraulic nut aswell as for applying the oil injection method, isavailable from SKF. Additional information aboutthese products can be found in the sectionMaintenance and lubrication products, startingon page 1069.

When using an SKF hydraulic nut for mount-ing it has to be positioned onto a threaded

section of the journal or onto the thread of thesleeve so that its annular piston abuts the innerring of the bearing, a nut on the shaft, or a discattached to the end of the shaft. Pumping oilinto the hydraulic nut displaces the piston axial-ly with the force needed for accurate and safemounting. Mounting of a spherical roller bearingwith the aid of a hydraulic nut on

a tapered shaft seating is shown in fig. 11 an adapter sleeve is shown in fig. 12 a withdrawal sleeve is shown in fig. 13.

With the oil injection method, oil under highpressure is injected between the bearing andbearing seating to form an oil film. This oil filmseparates the mating surfaces and appreciablyreduces the friction between them. This methodis typically used when mounting bearingsdirectly on tapered journals ( fig. 14), but isalso used to mount bearings on adapter and

withdrawal sleeves that have been preparedfor the oil injection method. A pump or oil injec-tor produces the requisite pressure, the oil isinjected between the mating surfaces via ductsand distributor grooves in the shaft or sleeve.

Fig. 11

Fig. 12

Fig. 13

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The necessary ducts and grooves in the shaftmust be considered when designing the bear-ing arrangement. A spherical roller bearingmounted on a withdrawal sleeve with oil ductsis shown in fig. 15. The withdrawal sleeve ispressed into the bearing bore by injecting oilbetween the mating surfaces and tighteningthe screws in turn.

Determination of the interference fitBearings with a tapered bore are alwaysmounted with an interference fit. The reductionin radial internal clearance, or the axial displace-ment of the inner ring on its tapered seating isused to determine and measure the degree ofinterference.

Different methods can be used to measurethe degree of interference:

1. Measuring the clearance reductionwith a feeler gauge.

2. Measuring the lock nut tightening angle.3. Measuring the axial drive-up.4. Measuring the inner ring expansion.

A brief description of these four different methodsis provided in the following. More detailed inform-ation about these methods can be found in therelevant product sections.

Fig. 14

Fig. 15

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Measuring clearance reductionwith a feeler gaugeThe method using feeler gauges for measuringthe radial internal clearance before and aftermounting bearings is applicable for medium and

large-sized spherical and toroidal roller bear-ings. The clearance should preferably be meas-ured between the outer ring and an unloadedroller ( fig. 16).

Measuring the lock nut tightening angleMeasuring the lock nut tightening angle is aproven method to determine the correct degreeof interference in small to medium-sized bear-ings on tapered seatings ( fig. 17). Guidelinevalues for the tightening angle ahave been

established, providing accurate positioningof the bearing on its tapered seating.

Measuring the axial drive-upMounting bearings with a tapered bore can bedone by measuring the axial drive-up of theinner ring on its seating. Guideline values for therequired axial drive-up are given in the text pre-ceding the relevant product table sections.

However, a more suitable method is theSKF Drive-up Method. This mounting method

provides a reliable and easy way to determinethe degree of interference. The correct fit isachieved by controlling the axial displacement ofthe bearing from a predetermined position. Themethod incorporates the use of an SKF hydrau-lic nut fitted with a dial indicator, and a speciallycalibrated digital gauge mounted on a selectedpump ( fig. 18). Determined values of therequisite oil pressure and the axial displacementfor the individual bearings provide accuratepositioning of the bearings. These values can befound

in the handbook SKF Drive-up Method onCD-ROM,

in the SKF Interactive Engineering Cata-logue online at www.skf.com or

online at www.skf.com/mount.

Fig. 16

Fig. 17

Fig. 18

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Measuring the inner ring expansionMeasuring inner ring expansion is a simple andvery accurate method to determine the correctposition of large-size spherical and toroidalroller bearings on their seatings. For this kind

of measurement the SensorMountis available,using a sensor, integrated with the bearinginner ring, a dedicated hand-held indicator andcommon hydraulic mounting tools ( fig. 19).Aspects such as bearing size, shaft smoothness,material or design solid or hollow do notneed to be considered.

Test running

After mounting a bearing, the prescribed lubri-

cant is applied and a test run made so that noiseand bearing temperature can be checked.

The test run should be carried out underpartial load and where there is a wide speedrange at slow or moderate speed. Underno circumstances should a rolling bearing beallowed to start up unloaded and accelerated tohigh speed, as there is a danger that the rollingelements would slide on the raceways and dam-age them, or that the cage would be subjectedto inadmissible stresses. Reference should be

made to the section Minimum load in the textpreceding the relevant product table sections.

Any noise or vibration can be checked usingan SKF electronic stethoscope. Normally, bear-ings produce an even purring noise. Whistlingor screeching indicates inadequate lubrication.An uneven rumbling or hammering is due inmost cases to the presence of contaminants in

the bearing or to bearing damage caused duringmounting.

An increase in bearing temperature imme-diately after start up is normal. For example, inthe case of grease lubrication, the temperature

will not drop until the grease has been evenlydistributed in the bearing arrangement, afterwhich an equilibrium temperature will bereached. Unusually high temperatures or con-stant peaking indicates that there is too muchlubricant in the arrangement or that the bearingis radially or axially distorted. Other causes arethat the associated components have not beencorrectly made or mounted, or that the sealshave excessive friction.

During the test run, or immediately after-

wards, the seals should be checked to see thatthey perform correctly and any lubricationequipment as well as the oil level of an oil bathshould be checked. It may be necessary tosample the lubricant to determine whether thebearing arrangement is contaminated or com-ponents of the arrangement have become worn.

Fig. 19

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Dismounting

If bearings are to be used again after removal,the force used to dismount them must never beapplied through the rolling elements.

With separable bearings, the ring with therolling element and cage assembly can beremoved independently of the other ring. Withnon-separable bearings, the ring having thelooser fit should be withdrawn from its seatingfirst. To dismount a bearing having an interfer-ence fit, the tools described in the following sec-tion may be used, the choice of tools will dependon bearing type, size and fit.

Dismounting bearingswith a cylindrical bore

Cold dismountingSmall bearings may be removed from their seat-ings by applying light hammer blows via a suit-able drift to the ring face, or preferably by usinga puller. The claws of the puller should be placedaround the side face of the ring to be removed,or an adjacent component ( fig. 20), e.g. alabyrinth ring etc. Dismounting is made easier if

provision is made for slots in the shaft and/orhousing shoulders to take the claws of thepuller, or

tapped holes are provided in the housingshoulders to take withdrawal screws( fig. 21).

Larger bearings mounted with an interfer-ence fit generally require greater force toremove them, particularly if, after a long periodof service, fretting corrosion has occurred. Useof the oil injection method considerably facili-tates dismounting in such cases. This presup-poses that the necessary oil supply ducts anddistributor grooves have been designed into thearrangement ( fig. 22).

Hot dismountingSpecial induction heaters have been developedto dismount the inner rings of cylindrical roller

bearings having no flanges or only one flange.They heat the inner ring rapidly without anyappreciable heating of the shaft, so that theexpanded inner ring can be removed easily.These electrical induction heaters ( fig. 23)

Fig. 20

Fig. 21

Fig. 22

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have one or more coils energized by alternat-ing current. It is necessary to demagnetize theinner rings after heating and removal. The useof electric withdrawal tools becomes economicwhen bearings of the same size are frequently

mounted and dismounted.When flangeless inner rings of cylindrical

roller bearings, or those with only one flange,which have not to be removed frequently, or iflarger sizes of inner rings (up to approximately400 mm bore diameter) have to be dismounted,it is less costly and also easier to use a so-calledthermo-withdrawal ring also referred to as aheating ring. This is a slotted ring, generally oflight alloy, with handles ( fig. 24).

The above-mentioned heaters and heating

rings are available from SKF. Additional informa-tion can be found in the section Maintenanceand lubrication products, starting on page1069.

Fig. 23

Fig. 24

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Dismounting bearingswith a tapered bore

Dismounting bearing on a tapered journalSmall and medium-sized bearings on a tapered

journal can be dismounted using conventionalpullers, which engage the inner ring ( fig. 25).Preferably a self-centring puller should be usedto avoid damage to the bearing seating. Bear-ings on tapered seatings normally loosen veryquickly. Therefore, it is necessary to provide astop of some kind, a lock nut for example, toprevent the bearing from being completelywithdrawn from the shaft.

The dismounting of large bearings fromtapered journals is greatly eased if the oil injec-

tion method is employed. After injecting pres-surised oil between the mating surfaces, thebearing will separate suddenly from its seating.A stop must therefore be provided, for example,a shaft nut or end plate, to limit the axial move-ment of the bearing to somewhat more than thedrive-up distance ( fig. 26).

Fig. 25

Fig. 26

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Dismounting bearing on an adapter sleeveSmall and medium-sized bearings on an adapt-er sleeve and smooth shafts can be dismountedby hammer blows directed to a drift ( fig. 27)until the bearing becomes free. But first the

sleeve nut has to be loosened a few turns.Small and medium-sized bearings on an

adapter sleeve and stepped shafts againsta support ring can be dismounted by usinga dolly abutting the sleeve nut, which has beenreleased by a few turns ( fig. 28).

Dismounting large bearings from an adaptersleeve with a hydraulic nut has proved easy todo. To use this technique however, the bear-ing must be mounted against a support ring( fig. 29). If the sleeves are provided with

oil supply ducts and distributor grooves thedismounting becomes easier because the oilinjection method can be employed.

Dismounting bearing on a withdrawal sleeveWhen dismounting bearings on withdrawalsleeves, the axial locking device a locking nut,end cover etc. has to be removed.

Small and medium-sized bearings can be dis-mounted using a lock nut and a hook or impactspanner to free the bearing ( fig. 30).

Fig. 27

Fig. 28

Fig. 29 Fig. 30

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The preferred means of dismounting largebearings is by using a hydraulic nut. If thethreaded section of the sleeve protrudes beyondthe shaft end or shaft shoulder, a support ringhaving the greatest possible wall thickness

should be inserted in the sleeve bore to preventdistortion and damage to the thread whenthe hydraulic pressure is applied. SKF recom-mends providing a stop behind the hydraulicnut, e.g. through an end plate at the shaft end( fig. 31). The use of a stop prevents thewithdrawal sleeve together with the hydraulicnut from being completely withdrawn from theshaft if the sleeve would separate suddenly fromits seating.

Withdrawal sleeves for large bearings are

generally provided with distributor ducts andgrooves for the oil injection method to saveconsiderable time when mounting as well asdismounting large bearings ( fig. 32).

Fig. 31 Fig. 32

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Bearing storage

Bearings can be stored in their original packag-ing for many years, provided that the relativehumidity in the storeroom does not exceed 60 %

and there are no great fluctuations in tempera-ture. The storeroom should also be free of vibra-tions and shaking.

With sealed or shielded bearings it may befound that the lubricating properties of thegrease with which they are filled may havedeteriorated if the bearings have been storedfor a long time. Bearings that are not stored intheir original packaging should be well protectedagainst corrosion and contamination.

Large rolling bearings should only be stored

lying down, and preferably with support forthe whole extent of the side faces of the rings.If kept in a standing position, the weight ofthe rings and rolling elements can give rise topermanent deformation because the rings arerelatively thin-walled.

Inspection and cleaning

As with all other important machine compon-ents, ball and roller bearings must be frequentlycleaned and examined. The intervals between

such examinations depend entirely on the operat-ing conditions.

If it is possible to ascertain the condition ofthe bearing during service, e.g. by listening tothe sound of the bearing when it is running andmeasuring the temperature or examining thelubricant, then it is usually found sufficient ifthe bearings (rings, cage and rolling elements)and other parts of the bearing arrangementare thoroughly cleaned and inspected annu-ally. Where the load is heavy, the frequency of

inspection must be increased, e.g. rolling millbearings are often inspected when the rolls arechanged.

After the bearing components have beencleaned with a suitable solvent (white spirit,paraffin etc.) they should be oiled or greasedimmediately to prevent corrosion. This is par-ticularly important for bearings in machines thatare left to stand for considerable periods.

Documents

6000 en 00 08 Mounting and Dismounting