54 Organi di trasmissione - novembre 2010 BEARINGS Giangiacomo Colleoni and Giulio Bianchi As big size rolling bearings are going to play an essential role in proper operation of complex machinery, their design and production call for wise quality-oriented decisions by the manufacturer, under pain of unexpected faults or, still worse, machine downtimes. Big dimensions require expertise ason, it is a matter of primary importance to know the data of the application where the bearing will be mounted on (specifications, exploitation, technical diagram, load, speed, operating temperature, misalignments, lubrication type, etc.) in order to select the adequate product, mainly in terms of total cost of ownership, thus reducing at the minimum the risk of unsuitable parameters, which can cause serious drawbacks. In the light of the fact that big size bearings are going to carry out a criti- Big size rolling bearings for heavy industry are costly and require long production times and therefore long delivery times. As a result, users are generally anxious about having at their disposal the spare to be used in case of unexpected faults or damages which can lead to extremely long and burdensome machine downtimes when the backup part is not immediately available. For this re- Big size RKB bearings installed on a typical speed multiplicator for megawatt class wind turbines. 10 novembre 2010

novembre 2010 - Organi di trasmissione 55 cal function for proper operation of complex expensive machinery, nothing can be left to chance and selections should be made with highest level of awareness and information. RKB Bearing Industries, the Swiss bearing manufacturer, has always been a specialist in all four main classes of radial and axial bearings (self-aligning, cylindrical roller, tapered roller and spherical roller bearings), with outside diameter up to 1,925 mm and mass of more than 4,000 kg. RKB defines as «T3» the segment containing its range of big size bearings, i.e. technological...

BEARINGS both after forging and heat treatments and rough-grinding, while MPI (magnetic inspection) is performed after finishgrinding. Furthermore, these procedures are assuring the Company Wide Quality Control, that is the constant real upgrading of each production cycle activity. Often customers ask the manufacturer of big size technological bearings for support during machinery design. This starts with technical analysis for the selection of the most suitable bearing type, coupling and lubrication to arrive at a real co-engineering activity that is performed by their respective technical departments...