super precision bearings

SPEEDSSpeedsThe speeds attainable by a specificbearing arrangement depend onthe overall energy balance of thesystem. The number of bearings,their position, internal stress (clearanceor preload), external stressand lubrication on the one hand aswell as the heat dissipation conditionson the other hand are the decisivefactors here. The attainablespeed figures in the bearing tablesare guide values that may be higheror lower, depending on thementioned conditions.Bearing ArrangementLarge bearing distanceLocating bearingFloating bearingFactor f rBearing PreloadL M H0.85 0.75 0.50.8 0.7 0.50.75 0.65 0.450.75 0.6 0.350.65 0.5 0.30.65 0.5 0.3Spindle Bearings0.72 0.57 0.37The attainable speeds stated in thebearing tables are an indication ofthe speed-ability of elastically preloadedsingle bearings. Thesespeeds are not attained by rigidlypreloaded bearings, bearing pairsor groups. The reduction factors tobe assumed here are shown inTable 32.Angular Contact Thrust BallBearings of Series 7602, 7603and BSBThe permissible speeds for greaselubricatedbearings are shown inthe bearing table. The indicatedvalues apply to a bearing pair inback-to-back or face-to-facearrangement. For other bearingarrangements the reduction factorsaccording to Table 33 have to beused.32: Speed reduction (n* · f r ) for spindle bearing setsBearing ArrangementAttainable Speeds1.0 · n*0.70 · n*0.85 · n*0.75 · n*0.65 · n** Speed see bearing tables33: Speed reduction for angular contact thrust ball bearing setsFAG · 174