Page 117 - The Tribology Handbook

A20 Selection of rolling bearings

Table 20.2

Design of bearing Factor A Remarks
Single row deep groove ball bearings Normal 500 000 Pressed steel cage
Maximum 1 000 000 Solid cage
Maximum 1 500 000 Solid cage, spray lubrication
Self-aligning double row ball bearings Normal 500 000 Pmsed steel cage
Maximum 800 000 Solid cage
-~
Angular contact single row ball bearings, a = 40 Normal 400 000 Pressed steel cage
Maximum 650 000 Solid cage, carefully controlled oil lubrication
a = 15 Maximum 1 000000 Solid cage

Angular contact double row ball bearings, Normal 200 000
Maximum 400 000 C3 clearance (greater than normal)
Cylindrical roller single row bearing Normal 400 OOO Pressed steel cage
Maximum 800000 Solidcage
Cylindrical roller double row bearings Normal 500000
Maximum 1000000 Oil lubrication
Maximum I 300 000 Spray lubrication, maximum precision

Spherical roller bearings Normal 200 000 For a predominantly axial load, limitsof 150oOO (grease
Maximum 400 000 lubrication) and 250 000 (oil lubrication) are used
Tapered roller single row bearings Normal 200 000 For a predominantly axial load 2@40% lower values
Maximum 400000 should be assumed, depending on difficulty of
working conditions

Table 20.3
15 000
Type ofbearing Factor A Remarks
10 000
Angular con- Normal 250 000 Grease lubrication
tact thrust Normal 300000 Oil lubrication
ballbearings Maximum 400000 Oil lubrication, cooling 5000
Thrust ball Normal 100000 _-
C
bearings Maximum 200000 Solid cage E 2000
>
Spherical Normal 200 000 Oil lubrication L
roller thrust Good natural cooling %z* 1000
bearings usually sufficient
Maximum 400 000 Effective cooling required 500
400
300
Speed limits for thrust bearings 200

An approximate guide to limiting speeds can be obtained
from the curves in Fig. 20.4. These are based on the 100 0
expression 35 45 60 100 140 180 250
nTH =f1f2 A, m
where H equals the height of bearing in mm (for double Fig. 20.4.
row angular contact thrust ball bearings H/2 replaces H).
All other factors are as for radial bearings.
Ball and roller thrust bearings for high-speed applications
must always be preloaded or loaded with a minimum axial
force and the bearing manufacturer should be consulted.
A20.4