NKE Hauptkatalog / General Catalogue 2011

Handling, Mounting andDismounting Rolling BearingsDismounting BearingsThe vast majority, about 90 per cent, of all rollingbearings are never removed from their locations,they stay in their machines or plants until thewhole machine is scrapped.This is why the replacement of bearings affectsmainly large and larger rolling bearings, andbearings for important machinery where it ispart of planned preventative maintenanceprogrammes.It is particularly important that when bearingsare frequently dismounted and remountedspecial care should be taken at all times to avoiddamage.In principle, the dismounting of a bearing positionis the opposite way to their mounting. This meansbearings with loose fi ts should be dismounted first(fi g. 10.30).GeneralThe ease of removal of rolling bearings is usuallydependent on the dismounting possibilitiesconsidered and included in the machine design.Particularly when dealing with machines or unitsthat are known to require specific maintenanceduring their service life, including their frequentremoval, quite simple and effective designfeatures ease bearing removal signifi cantly.Such design measures may be pressure screws,dismounting threads and holes, or suitable slotsor recesses on housings or shafts.Fig. 10.30The separable bearing types also present someadvantages at removal (see fi g. 10.31).Preparations for DismountingThe dismounting of bearings require some basicpreparation, similar to when mounting rollingbearings, including careful study of manuals,machine plans and maintenance procedureswhich give appropriate information.To ensure the successful replacement of anybearing all machine surfaces surrounding the areato be dismounted must be cleaned to eliminatethe entrance of avoidable contamination,including production swarf and waste prior to anydismounting.Also, all tools and auxiliary equipment to be usedmust be clean and in a good condition.Fig. 10.31www.nke.at 365