Page 688 - Rollingbearings

8 Tapered roller bearings
Permissible speed

The speed ratings in the product tables
indicate:

• the reference speed, which enables a
quick assessment of the speed capabilities
from a thermal frame of reference
• the limiting speed, which is a mechanical
limit that should not be exceeded unless
the bearing design and the application are
adapted for higher speeds

For additional information, refer to Operating
temperature and speed, page 130.

Table 8
for calculating comparative rating life
Equivalent dynamic bearing load P F

Bearing arrangement Load case Comparative equivalent
dynamic radial load

F r F r
1a) F ≤ 0,6 F rL /K L P FL1 = 0,5 F rL + 0,83 K L F a
a
8 P FL2 = 0,5 F rL - 0,83 K L F a
P FN = F rN
F a
1 2
Locating Non-locating
1b) F > 0,6 F /K L P FL1 = 0,4 F + K F
a
rL
L a
rL
P FL2 = 0
P = F rN
FN
F r F r
1c) F a = 0
F a P FL1 = F rL
P = F
1 2 FN rN
Locating Non-locating

Values of the thrust factor K L are listed as K in the product tables.
For load cases 1a) and 1b), the load rating for one roller row needs to be applied when using P FL .
The load rating for one roller row can be obtained from

C F(row) = 0,58 C F(bearing)

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