The document discusses super finishing processes which are used to remove defects from grinding operations and achieve a high surface quality. It describes three main super finishing processes: honing, lapping, and super finishing. Honing is used to finish bores and involves rotating abrasive stones to cut metal. Lapping uses abrasives and less pressure/heat to produce highly accurate flat surfaces. Super finishing is a type of honing that uses less pressure, higher speeds, and more lubricant to produce smooth external surfaces with minimal heat. The goal of these processes is to improve the dimensional accuracy and surface finish of parts.

1. PREPARED BY:-
Nitesh Choudhary
Super finishing
processes

2. WHY SUPER FINISHING REQUIRED
Parts Worn Out Fast Due To Defects Of Grinding
Operation.
The Defects Are Chatter Marks, Helical Type
Scratches, Surface Cracks, Smear Metal etc. are
Responsible For Wearing Out The Parts.
In Certain Circumstances High Surface Quality Is
Required.
Hence For Removing Grinding Defects, To Obtain
Desired Surface Finish And To Improve The
Geometrical Shape Finishing Processes Are Used.
It Includes Honing, Lapping, And Super Finishing.

3. TYPES OF SUPER FINISHING
PROCESS
a) Honing
b) Lapping
 Hand Lapping
 Machine Lapping
c) Super Finishing

4. HONING
• Hole made by boring is obtained to required dimension and
finishing by honing.
• In this process abrasive stone is used.
• The dimension to an accuracy of 0.005 mm can be obtained
by honing process

5. • Honing is wet cutting
process. 6 to 8 honing sticks
are held together and metal
is removed by rotating or
reciprocating the holder.
• Honing tool is rotated at a
speed of 0.5 - 2.5 m/s and
reciprocates at a speed of
0.2 – 0.5 m/s.

6. • Objectives are achieved by honing
1. Metal is removed
2. Roundness & straightness is obtained
3. Accurate dimension is obtained
4. Required surface finish is obtained.
5. Less complex or low cost fixtures.
It is highly accurate.
6. It can be used for both long and short bores.
7. It maintains original bore centreline.
8. Any material can be finished regardless its hardness.
•Application :
-Honing Of Automobile
Cylinder
-Honing Is Also Used For
Repair Work

7. LAPPING
• Lapping is a machining process in which two
surfaces are rubbed together with
an abrasive between them, by hand movement
or using a machine.
• Abrasive compound or solid bonded
abrasive is used in it. More accuracy is
obtained as heat & pressure are less in
lapping.
• Lapping compound is made by mixing
diamond, silicon carbide, aluminum oxide in
oil or water.
• There are many types of lapping process.

8. HAND LAPPING
• In this method lapping
compound is spread on cast
iron plate and work piece is
moved manually on it on a
path.

9. Machine lapping
• In this method a rotating table
is used in place of the plate.
Again the work piece to be
lapped is given rotary by a
cage and rotated on the
surface of the table. Rotating
lap is used above & below the
work piece to produce parallel
surfaces.

10. - Machine lapping process is carried out for gauge
blocks, piston pin, ball bearings and engine valves.
Application of lapping:-

11. SUPER FINISHING
• This process is one type of
honing , in which as compared
to the honing less
pressure, high speed, huge
amount of lubricant – coolant of
low viscosity and more contact
area between work & abrasive
face is kept. Less heat is
produced during super finishing
and it is generally done on
external surfaces.

12. POLISHING
• Abbrasive material is bond
to a tool (disc, belt) or it is a
media (paste) freely between
tool (textile disc, belt) and
part
• NO improve in shape or
accuracy!!
• Just improves the surface
quality

13. Thank you