3. Contents
Special features of CNC Turning and Milling
centers
Classification of CNC Machining centres
Configuration of CNC Machine control unit
Advantages of CNC Turning and Milling
centres
Introduction to CNC, Turning and Milling
operations
4. CNC:-
It indicates “Computer and Numerically controlled”, It is defined
“Automation of machine tools operated by precisely programmed
commands with computer playing important role of control ”
Milling:-
Milling is a machining operation of producing flat, helical surfaces
means of multiple cutting edged rotating tools called “Milling
Cutters”. After the advent of computer numerical control (CNC),
milling machines evolved into milling machining centers
6. Automatic tool changer :-
The tools are contained in a storage unit that is integrated with the
machine tool. When a cutter needs to be changed, the tool drum rotates
to the proper position and an automatic tool changer (ATC) operating
under program control.
Automatic work part positioner :-
Many horizontal and vertical machining centers have the capability to
orient the work part relative to the spindle. This is accomplished by
means of a rotary table on which work part is fixtured. The table can
be oriented at any angle about a vertical axis to permit the cutting tool
to access almost the entire surface of the part in a single setup.
7.
8. CNC milling is a specific form of
computer numerical controlled (CNC)
machining. Milling itself is a machining
process similar to both drilling and
cutting, and able to achieve many of the
operations performed by cutting and
drilling machines. Like drilling, milling
uses a rotating cylindrical cutting tool.
13. CNC Turning is manufacturing process in which a
round(cylindrical) material is held in a chuck and
rotated while a tool is fed to the piece to remove
material to create the desired shape. CNC lathes or
turning centers have tooling mounted on a turret
which is computer-controlled. CNC’s with “live”
tooling
14. Designed mainly for machining shaft-type work pieces
supported by chuck and heavy-duty tailstock center
On four-axis machines, two opposed turrets, mounted
on separate cross-slides
One above and one below center line of work
Balance cutting forces so extremely heavy cuts can
be taken on work piece
15. Steady rest
◦ Allow facing and threading on end of shafts
Follower rest
◦ Used to support long, thin shafts
Bar-feeding mechanism
◦ Permits machining of shafts and parts from
bar stock smaller than spindle through-hole
Production part loader
◦ Can complete part changeover when
individual precut shafts machined
16. Reduced lead time
Elimination of operator errors
Less Operator activity
Less Labor Cost
Longer Tool Life
Elimination of special Jigs and
Fixtures
Flexibility in changes of product
design
Reduced inspection
Reduced Scrap
Accurate costing and scheduling