Loads

Minimum load

For additional information → Requisite minimum load

The minimum load requirements can be ignored for bearings operating at the relatively low speeds shown within the green area in diagram 1.

For operating speeds outside the green area use:

Catalogue image - Fam - minimum load

Catalogue image - Flub for v n gt or eq 2000

Catalogue image - Flub for v n lt 2000

Perform calculations

Equivalent dynamic bearing load

For additional information → Equivalent dynamic bearing load, P

Fr ≤ 0,55 Fa and:

  • if run-out in the bearing arrangement does not affect the load distribution in the spherical roller thrust bearing
    → P = 0,88 (Fa + X Fr)
  • if run-out in the bearing arrangement affects the load distribution in the spherical roller thrust bearing (e.g. the run-out of another bearing that induces radial forces)
    → P = Fa + X Fr

Fr > 0,55 Fa → Use an additional bearing, which  accommodates the radial load.

Perform calculations

Equivalent static bearing load

For additional information → Equivalent static load

Fr ≤ 0,55 Fa → P0 = Fa + X0 Fr

Fr > 0,55 Fa → Use an additional bearing, which  accommodates the radial load.

Symbols

A
minimum load factor (→ product table)
Cr
load factor
= 1,8 for 292 series
= 2,0 for 293 series
= 2,2 for 294 series

bearing outside diameter [mm]
d
bearing bore diameter [mm]
f0factor for lubrication method.

For oil bath lubrication with a horizontal shaft and for grease lubrication:
= 3 for 292 series
= 3,5 for 293 series
= 4 for 294 series

For oil bath lubrication with a vertical shaft and for oil jet lubrication:
= 6 for 292 series
= 7 for 293 series
= 8 for 294 series
Fam
minimum axial load [kN]
Flub axial load required to overcome lubricant drag [kN]
Fr
radial load [kN]
n
rotational speed [r/min]

equivalent dynamic bearing load [kN]
P0 
equivalent static bearing load [kN]
X
calculation factor
= 1,1 for 292 series
= 1,2 for 293 series
= 1,3 for 294 series
X0
calculation factor
= 2,5 for 292 series
= 2,7 for 293 series
= 2,9 for 294 series
ν
actual operating viscosity of the lubricant [mm2/s]  
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