Minimum load

For additional
(→ Requisite minimum load)

Perform calculations

The weight of the components supported by the bearing, together with external forces, generally exceed the requisite minimum load. If this is not the case, the bearing must be subjected to an additional radial load. Axial preload can be applied by adjusting the inner and outer rings against each other, or by using springs.
Axial load carrying capacityPure axial load → Fa ≤ 0,25 C0

Excessive axial load can lead to a considerable reduction in bearing service life.
Equivalent dynamic bearing load

For additional
(→ Equivalent dynamic bearing load)
Fa/Fr ≤ e → P = Fr

Fa/Fr > e → P = X Fr + Y Fa

Perform calculations
Equivalent static bearing load

For additional
(→ Equivalent static bearing load)
P0 = 0,6 Fr + 0,5 Fa

P0 < Fr → P0 = Fr


C0=basic static load rating [kN] (→ product tables)
dm=bearing mean diameter [mm]
= 0,5 (d + D)
e=limit for the load ratio depending on the relationship f0 Fa/C0
(table 1)
f0=calculation factor (→ product tables)
Fa=axial load [kN]
Fr=radial load [kN]
Frm=minimum radial load [kN]
kr=minimum load factor (→ product tables)
n=rotational speed [r/min]
P=equivalent dynamic bearing load [kN]
P0=equivalent static bearing load [kN]
X=calculation factor for the radial load (table 1)
Y=calculation factors for the axial load depending on the relationship f0 Fa/C0 (table 1)
ν=actual operating viscosity of the lubricant [mm2/s]
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