MILLING MACHINE PPT WORKING PRINCIPLE ,MILLING METHODS AND SPECIFICATIONS OF MILLING MACHINES

1. LENDI INSTITUTE OF ENGINEERING
AND TECHNOLOGY
METAL CUTTING AND MACHINE TOOLS
COURSE CODE: C302
REGULATION: R16
3rd BTECH 1st SEM
PREPARED BY :
POLAYYA CHINTADA M.TECH,M.B.A,(PhD)
ASSISTANT PROFESSOR
TOPIC:
MILLING MACHINES

2. MILLING MACHINES:
milling
Milling is a process performed with a machine in which the
cutters rotate to remove the material from the work piece
present in the direction of the angle with the tool axis.
The machined surface may be flat, angular, or curved.
The surface may also be milled to any combination of
shapes.
One or more number of cutters can be mounted
simultaneously on the arbor of the milling machine
The cutting tool used in milling operation is called milling
cutter, which has of numerous edges call teeth
Milling machine is used for machining flat surfaces,
contoured surfaces, surfaces of revolution, external and
internal threads, and helical surfaces of various cross-
sections.
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3. Working Principle :
In this work is rigidly clamped on the table of the
machine while revolving multi teeth cutter mounted
either on the spindle or on an arbor. The cutter revolves
at high speed and the work is fed slowly past the cutter. The
work can be fed vertical, longitudinal, or cross direction. As
the work advances, the cutter teeth remove the metal from
the work surface to produce the desired shape.
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MILLING MACHINES:

4. MILLINGMETHODS:
There are two distinct methods of milling classified as
follows:
1. Up-milling or conventional milling
2. Down milling or climb milling.
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MILLING MACHINES:
Up-milling or conventionalmilling
In the up-milling the metal is removed in the form of small
chips by a cutter rotating against the direction of travel of the
work piece.
 In this type of milling, the chip thickness is minimum at the start
of the cut and maximum at the end of the cut. As a result the
cutting force also varies from zero to the maximum value per
tooth movement of the milling cutter.
 The major disadvantages of the up-milling process are the
tendency of cutting force to lift the work from the fixtures and poor
surface finish obtained. But being a safer process, it is a
commonly used method of milling

5. MILLINGMETHODS:
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MILLING MACHINES:
Down-milling or climbmilling
In this method, the metal is removed by a cutter rotating in
the same direction of feed of the work piece.
Chip thickness is maximum at the start of the cut and minimum
in the end. In this method, there is less friction involved and
consequently less heat is generated on the contact surface of the
cutter and work piece.
Climb milling can be used advantageously on many kinds of
work to increase the number of pieces per sharpening and to
produce a better finish.
With climb milling, saws cut long thin slots more satisfactorily
than with standard milling. Another advantage is that slightly lower
power consumption is obtainable by climb milling since there is no
need to drive the table against the cutter.

7. SPECIFICATIONS OF MILLINGMACHINES :
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MILLING MACHINES:

8. Yours:
POLAYYA CHINTADA M.TECH,M.B.A,(PhD)
ASSISTANT PROFESSOR