Bearing Load Rating and Lifetime Information || Dynaroll

TECHNICAL INFORMATION

LOAD RATING & LIFETIME

MAXIMUM STATIC LOAD Co

When subjected to an excessive load or shock, rolling bearings may incur a permanent damage to the raceways, called brinelling. This occurs when the elastic limit of the raceway material is exceeded and will permanently effect the smooth rotation of the bearing.

The maximum static load rating of a bearing (Co) is defined as that load which will produce a contact stress of 609,000 lbf /in2 (428 kgf/mm2) between the rolling element (ball) and the raceway. The values of Co are listed in the bearing tables for each individual bearing. Exceeding this value will damage the bearing.

MAXIMUM STATIC LOAD Co

In most cases, the actual load applied to a bearing is a combination of fluctuating radial and axial loads which cannot be directly used for fatigue life calculations. Instead, the Equivalent Load (P) is used. This represents the hypothetical load of constant magnitude, passing through the center of the bearing, that would give the actual observed bearing life when used in the fatigue life formula. It is an estimate, dependent on the initial ball contact angle αo and the static capacity of the bearing Co, as well as the actual load applied (F).
P = Pr + Pa
where:  
Pr , Pa are equivalent radial and axial equivalent loads, calculated using the nomographs below.
EQUIVALENT AXIAL LOAD NOMOGRAPH (LBS. OR KG)


EQUIVALENT RADIAL LOAD NOMOGRAPH (LBS. OR KG)


Useful link: Bearing failure