Basic centreless grinding machine

2. In this type of grinding
the workpiece is not held
in between centres. So it
is called as centrelless
grinding. This method of
grinding is used for mass
production of similar
objects.it is used to grind
cylindrical, tapered and
formed surfaces on
workpieces.

3. There is no need to prepare
the workpiece to hold it in
between centres (i.e.
countersunk holes need not
be produced at the end
faces of the work).
Since the workpiece is
supported through out its
operation, there is no
bending and vibration. So
very thin and lengthy
workpiece can be easily
ground.
Since less material is
remove, there is less wheel
wear and the grinding time is
less.
Since the job is not held
between centres and floads
in between the wheels, there
is no material to make it true.
Semi skilled workers can be
used.

4. Difficult to obtain accuracy in hollow workpieces.
Workpiece with irregular shapes are difficult to grind i.e.
workpiece with number of steps is difficult to handle.

5. Through
feed
• In this method the
workpiece fed in one
end comes out in the
other end as a finished
product. it completely
passes through the
space between the
wheels. Guides are
provided in both ends.
This method is used
only for cylindrical
pieces without any
step. It is used for
grinding piston pins,
long and thin shafts.
End feed
• In this method the job
is moved until it hits on
the end stop. But not
moved through out.
Because it is moved
until the end stop, it is
called as end feed.
This method is
commonly used for
producing tapered job.
Both the wheels (or
single wheel) may be
formed to the required
taper shape.
In feed
• This method is similar
to plunge grinding or
form grinding. The
workpiece is not moved
through. After placing
the work on the
workrest, the regulating
wheel is moved in, to
feed the work against
the grinding wheel.
After the operation is
over the regulating
wheel is moved back
and the workpiece is
removed.

7. The principle of centerless internal grinding is similar to centerless
external grinding. In this machine (or process) the work is supported by
three rolls. They are a) Regulating roll. b) Supporting roll and c) Pressure
roll. The regulating roll (as in centerless external process) regulates the
speed and feed. The supporting roll supports the workpiece. The pressure
roll helps to hold the work firmly against the support and regulating rolls.
The contact of the grinding wheel is exactly opposite to the regulating roll.
This arrangement assures uniform wall thickness and concentricity. The
pressure roll can be made to swing towards and away from the
workpiece. This enables loading and unloading of the workpiece

9. 1) SUMBER INTERNET
a) https://en.m.wikipedia.org/wiki/Centerless_grinding
b) www.sc-grinder.com/centerless-grinder .html
1) SUMBER ILMIAH
a) Perpustakaan Kolej Vokasional Klang
 Singh, G. Balagi
• Machineshop technology / G. Balagi Singh.
• ISBN 978-967-950-246-6
1. Machine-tools. 2. Machine-shop practice. I. Title.
• 621.902
•
 Machine technology / V. Varadarajan, N. Mariyappan.
• ISBN 978-967-950-304-3
1. Machine-TOOLS. 2. Machine-shop practice. I. N. Mariyappan. II. Title.
• 621.902