This International Standard specifies methods of calculating the basic static load rating and the static
equivalent load for rolling bearings within the size ranges shown in the relevant ISO standards, manufactured
from contemporary, commonly used, high quality, hardened bearing steel in accordance with good
manufacturing practice and basically of conventional design as regards the shape of the rolling contact
Calculations carried out in accordance with this International Standard do not yield satisfactory results for
bearings in which, because of application conditions and/or internal design, there is a considerable truncation
of the area of contact between the rolling elements and the ring raceways. The same limitation applies where
application conditions cause deviations from a normal load distribution in the bearing, for example
misalignment, preload or extra large clearance or where special surface treatment or coatings are used.
Where there is reason to assume that such conditions prevail, the user should consult the bearing
manufacturer for recommendations and the evaluation of the static equivalent load.
This International Standard is not applicable to designs where the rolling elements operate directly on a shaft
or housing surface, unless that surface is equivalent in all respects to the bearing surface it replaces.
Double-row radial bearings and double-direction thrust bearings are, when referred to in this International
Standard, presumed to be symmetrical.
In addition, guidelines are given for static safety factors to be applied in heavy loaded applications.