Milling is one of most important machining operations
which employ a multipoint cutting tool is called milling
In milling, the material is removed as the feed against a
rotating multipoint cutter. The cutter rotates in one direction
and the fixed on the table is adjusted vertically to get the
required depth of cut.
Types of milling Machines
Column and Knee type
a) Hand milling Machine
b) Plain (horizontal) Milling Machine
c) Universal Milling Machine
d) Omniversal Milling Machine
e) Vertical Milling Machine
Fixed bed type Milling Machine
Planer type Milling Machine
Special purpose machines
a) Rotary table milling machine
b) Planetary milling machine
c) Cam milling machine
d) Profile milling machine
Size of Milling Machine
The sizes of working surface of the table
The maximum length of longitudinal, cross and vertical
travel of the table.
The power of driving motor
Number of feeds
Floor space required
HORIZONTAL MILLING MACHINE
In milling operation the metal is removed from the
work piece by rotating milling cutter
In horizontal milling machine the axis of milling
cutter is parallel to the surface of work piece.
The work piece mounted on a table can be removed
in three directions at right angles to each other.
a) longitudinal direction to provide length of cut
b) Vertical direction to provide depth of cut
c) Transverse direction to provide width of cut
In normal operation the machine is operated in
only one direction at a time.
The main parts of horizontal milling machine are:
The work table
The over arm
Base: The base is a grey cast iron which supports the
column at its one end.
Column: It is a large mounted vertically on the base. On
the front of the column guide ways are provided to support
the knee. A dovetail slide is also provided on the top to the
hold an over arm.
Saddle: The saddle is moved horizontally towards or away
from the face of the column by turning the cross feed.
Worktable: The work table provides the longitudinal
movement to the work by hand. The table is provided with
T-slots for direct mounting of the work pieces.
Over arm: The over arm is located in the sideway at the
top of the column.
Arbor support: the arbor support is positioned on the
under side of the over arm. It provides support for the
Spindle: The machine spindle is located in the upper
part of the column and receives power from the motor
through belts, gears and clutches.
Arbor: it is fixed in the taper of the spindle nose. It
locates the cutters in position, and is driven by the
HAND MILLING MACHINE