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Deze reply is gepost in de afdeling Technical Forum in het onderwerp 'C3 of C4' (ID 13639).
De reply is geschreven door Rudy (UserID 655) op 26-11-2003 0:56.

http://www.skf.com/p...k=1_0_48&lang=en

Speeds above the speed rating

It is possible to operate bearings at speeds above the speed ratings quoted in the product tables if bearing friction can be reduced by lubrication with small, accurately metered quantities of lubricant, see under "Oil spot lubrication" for example, or when heat can be removed from the bearing by circulating oil lubrication with cooling of the oil, by cooling ribs on the housing, or by directed cooling air streams. Any increase in speed above the speed rating without taking any of these precautions would only cause bearing temperature to rise excessively. An increase of bearing temperature means that lubricant viscosity is lowered and film formation is made more difficult, leading to even higher friction and further temperature increases. If, at the same time, the operational clearance in the bearing is reduced because of increased inner ring temperature, the final consequence would be bearing seizure. Any increase in speed above the speed rating generally means that the temperature difference between inner and outer rings is greater than normal. Usually, therefore, an internal clearance of C3 which is greater than Normal is required, and it may be necessary to look more closely at the temperature distribution in the bearing.

http://www.skf.com/p...=1_0_166&lang=en

Dit bericht is ge-edit door Rudy op 26-11-2003 0:57