184 Machine Drawing
dharm
d:\N-Design\Des12-1.pm5
Outer race
Inner race
Balls
Cage
Fig. 12.11 Parts of a ball bearing
Locking washer
Fig. 12.12 Mounting of a radial ball bearing
Anti-friction bearings are further classified into: radial bearings and thrust bearings.
12.3.1 Radial Bearings
Radial bearings are used to resist normal (radial) loads acting on the shafts. These bearings
are sub-divided on the basis of the shape of the rolling elements used, viz., ball bearings, roller
bearings and taper roller bearings.
Figure 12.13 shows various types of anti-friction bearings, mounted on a common shaft.
From the figure, it may be seen that a single row radial bearing is shown in three different
sizes or series, viz., light, medium and heavy. The selection of a particular size depends upon
the magnitude of the load acting on the bearing. Sometimes, double row ball bearings are used
instead of single row ball bearings, to resist heavy loads.
Manufacturer's use a numbering system to denote the type of series (sizes) of the bearings.
For example 2xx, 3xx, 4xx series correspond to light, medium and heavy series respectively.
The last two digits when multiplied by 5, gives the bore or shaft size in millimetres. Thus 308
bearing signifies medium series bearing of 40mm bore. Additional digits if present, may refer
to manufacturer's details.
