Equivalent bearing loads

Equivalent dynamic bearing load

If individual single direction bearings, bearing sets, or double direction bearings have to accommodate both axial and radial loads, the equivalent dynamic bearing load for each direction of axial load can be determined as follows:

Fa/Fr ≤ 2,35 → P = X Fr + Y Fa

Fa/Fr > 2,35 → P = 0,97 Fr + Fa

For bearings that accommodate axial loads only:

P = Fa

where


P=equivalent dynamic load [kN]
Fr=radial load [kN]
Fa=axial load [kN]
X=radial load factor
– for single direction bearings: table 1
– for double direction bearings: 1,9
Y=axial load factor
– for single direction bearings: table 1
– for double direction bearings: 0,55

Preload is considered to be an axial load. For bearing sets in any arrangement, the equivalent dynamic bearing load must be calculated separately for each load direction.

Equivalent static bearing load

If individual single direction bearings, bearing sets, or double direction bearings have to accommodate both axial and radial loads, the equivalent static bearing load for each direction of axial load can be determined as follows:

P0 = Fa + 4,35 Fr

where


P0=equivalent static load [kN]
Fr=radial load [kN]
Fa=axial load [kN]

Preload is considered to be an axial load. For bearing sets, in any arrangement, the equivalent static bearing load must be calculated separately for each load direction.

The equation for equivalent static bearing load applies to individual bearings and for bearings in a tandem arrangement if the load ratio Fa/Fr is not lower than 4. When Fa/Fr is between 4 and 2,5 the equation still provides useable approximation values.

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