A bearing is a machine element that constraints relative motion to
only the desired motion.
Reduces friction between the moving parts.
Bearings provide support to the rotating shaft .
Bearings are provided with some lubrication to
3. JOURNAL BEARING
It is simply a block of cast iron with a
hole for the shaft providing running
Oil hole is drilled at the top for
4. JOURNAL BEARING:: Used to support the load on a rotating shaft.
OIL INLET ::Used to insert oil /lubrication
As lubricating oil is feed into the bearing and is dragged by the shaft
into the converging gap , the fluid pressure increases and a
hydrodynamic lift is created.
8. DISADVANTAGES OF JOURNAL
There is no provision for wear and adjustment on account of wear.
The shaft must be passed into the bearing axially i.e. endwise.
ADVANTAGES OF JOURNAL BEARING
It can handle high loads and velocities (less metal to metal contact due to oil
Long lasting and durable.
Quiet and smooth running of engine.
Suitable only for low temperatures and speed
Requires large supply of lubrication
9. PRESSURE DISTRIBUTION
A pressure is built up in clearance space when
the journal or shaft is rotating about an
axis(eccentric to bearing axis) and lubricant is
supplied to the bearing.
This pressure will resist the motion of the
shaft or journal.
Arise due to flow of viscous fluid in