Dynamic axial load carrying capacity
Double row and double row full complement cylindrical roller bearings with flanges on both the inner and outer rings can support axial loads up to Fa ≤ 0,25 Fr in addition to radial loads.
The axial load carrying capacity is determined by the lubrication condition, operating temperature and heat dissipation at the roller end / flange contact.
The formulae below are valid for normal operating conditions:
- ΔT ≈ 60 °C between the bearing operating and ambient temperature
- specific heat loss ≈ 0,5 mW/mm2
- viscosity ratio κ ≥ 2
Permissible axial loads
Conditions | Mechanical limitations | Thermal limitations |
Continuous | Fap max ≤ 0,0023 D1,7 | Circulating oil lubrication
Other lubrication
|
Brief periods |
Fap brief ≤ 2 (Fap, Fap oil, Fap max)
|
|
Occasionalpeak loads | Fap peak ≤ 3 (Fap, Fap oil, Fap max) |
Symbols
A | reference surface [mm2]
= π B (D + d) |
B | bearing width [mm] |
C0
| basic static load rating [kN] (→ product table) |
d
| bearing bore diameter [mm] |
D
| bearing outside diameter [mm] |
ΔTS
| temperature difference between incoming and outgoing oil flow [°C]
|
Fa | axial load [kN] |
Fap | permissible axial load [kN]
|
Fap brief
| maximal axial load for brief periods [kN]
|
Fap peak | maximal occasional axial peak load [kN] |
Fap max | maximal constantly acting axial load [kN]
|
Fap oil
| maximum permissible axial load in circulating oil applications [kN]
|
Fr | radial load [kN] |
k1 | lubrication factor
= 0,35 for oil lubrication = 0,2 for grease lubrication |
k2 | lubrication factor
= 0,1 for oil lubrication = 0,06 for grease lubrication |
n | rotational speed [r/min] |
VS
| amount of oil flow [l/min] |