NKE Hauptkatalog / General Catalogue 2011

Handling, Mounting andDismounting Rolling BearingsDepending on the individual manufacturer thebasic equipment supplied may vary. For theoptimum utilisation of induction heaters it is recommendedseveral yokes with different sectionbe used.Some types of induction heaters have yokes thatallow a skewing sideways. This design featureprovides a very simple method of handling theheated parts.When a single bearing or bearings of theuniversal matched design are used the requisiteclearance or preload must be adjusted duringmounting according to the individual applicationand bearing position.Values for the individual bearing clearance orpreload are defined either by design or, in thecase of maintenance work the instruction manuals.Warning:All types of induction heater create a verystrong magnetic field.Please read carefully the operating instructionsand consider the recommendationsand safety instructionsprovided by the supplier of your inductionequipment. Never use inductive actingequipment if you use a pace-maker!Always wear protective gloves when working withinduction heaters.To mount the heated parts position them carefullyand smoothly onto the seat up to and againstthe abutment face or shoulder, pressing the partfi rmly against the contacting surface until the parthas cooled down to the ambient temperature.This is important to ensure the correct positioningof the bearing.Mounting of Matched andAdjusted BearingsSeveral bearing types, such as tapered rollerbearing and angular contact ball bearing, areused in pairs.These pre-set bearing units, (e.g. tapered rollerbearing units or complete spindle bearing sets),are normally precisely matched by the manufacturerto enable a quick and simple mountingthus avoiding the time consuming and skillfuladjustment of the required clearance or preload.Fig. 10.25Fig. 10.25 shows the adjustment of a defined axialclearance of a pair of tapered roller bearings.In this example the axial clearance is adjusted bythe use of a lock nut.Prior to the bearing adjustment it is recommendedto rotate the shaft several times by hand toensure that the tapered rollers sit correctly in theguiding ribs of inner ring.For a measurement of the actual axial clearancethe shaft must be moved axially from one end ofthe stroke to the other (i.e. extremes).An alternative method of achieving the necessarybearing assembly adjustment is the use ofcalibrated master spacers.These spacers or shims are of predeterminedwidths which when fi tted between the respectivebearings determine the correct axial clearance(fi g. 10.26).www.nke.at 359