Choosing the Right CBSE School A Comprehensive Guide for Parents
Bearing
1. This topic explains the types of basic bearing such
as friction bearing, fluid coated bearing, rolling
bearing. This topic also explains the method of
selecting suitable bearing based on calculation of
dynamic and life load ratio.
By: M. Hamdi Bin Khosran JKM, PMM 1
2. žA bearing is any of various machine elements
that constrain the relative motion between
two or more parts to only the desired type of
motion. This is typically to allow and
promote free rotation around a fixed axis or
free linear movement; it may also be to
prevent any motion, such as by controlling
the vectors of normal forces. Bearings may
be classified broadly according to the
motions they allow and according to their
principle of operation, as well as by the
directions of applied loads they can handle.
By: M. Hamdi Bin Khosran JKM, PMM 2
3. ž A plain bearing, also known as a plane bearing[1] or a
friction bearing is the simplest type of bearing,
comprising just a bearing surface and no rolling
elements.
ž Therefore the journal (i.e., the part of the shaft in
contact with the bearing) slides over the bearing
surface.
ž The simplest example of a plain bearing is a shaft
rotating in a hole. A simple linear bearing can be a
pair of flat surfaces designed to allow motion; e.g., a
drawer and the slides it rests on or the ways on the
bed of a lathe.
ž Plain bearings, in general, are the least expensive
type of bearing. They are also compact and
lightweight, and they have a high load-carrying
capacity.
By: M. Hamdi Bin Khosran JKM, PMM 3
7. žA rolling-element bearing, also known as a
rolling bearing, is a bearing which carries a
load by placing round elements between the
two pieces. The relative motion of the pieces
causes the round elements to roll with very
little rolling resistance and with little sliding.
By: M. Hamdi Bin Khosran JKM, PMM 7
10. ž Fluid bearings are bearings which support the
bearing's loads solely on a thin layer of liquid or gas.
ž They can be broadly classified as fluid dynamic
bearings or hydrostatic bearings.
¡ Hydrostatic bearings are externally pressurized fluid
bearings, where the fluid is usually oil, water or air, and
the pressurization is done by a pump. Hydrodynamic
bearings rely on the high speed of the journal self-
pressurizing the fluid in a wedge between the faces.
¡ Fluid bearings are frequently used in high load, high
speed or high precision applications where ordinary ball
bearings have short life or high noise and vibration. They
are also used increasingly to reduce cost. For example,
hard disk drive motor fluid bearings are both quieter and
cheaper than the ball bearings they replace.
By: M. Hamdi Bin Khosran JKM, PMM 10
